Please Read...
10-20-2003, 09:57 AM
#1
Former Vendor
Thread Starter
Please Read...
Guys,
I have been talking with MANY people via email/phone/IM in regards to their setups. It seems that many of these people are experiencing roughly the same problems. Rough idles, poor gas milage, black smoke from the exhaust, ect.
These problems all seem to be linked to one common problem. Bad or lack of O2 sensors readings.
Once you understand how the ECM system works, you will realize that the 02 sensor is the #1 sensor that can make or break you.
Lets look at it in more detail. The ECM relies on feedback from the 02 sensor in order to correctly adjust fuel trims. This is a process that happens many times a second. The 02 monitors the exhaust gases and feeds the ECM information on the mixture. If the reading are lean, then the ECM will add fuel to the injectors trim to bring it to rich.
A key part of understanding how the system is suppose to work, is understanding what the 02 sensor telling the ECM with its readings.
A little information on the 02 sensor itself: The oxygen sensor itself is designed to generate a voltage based on the combustion mixture present in the exhaust system. To the 02 sensor itself the mixture this is either a rich mixture or a lean mixture. The o2 sensor was designed to be nothing more than a switch. Low readings less than .450 as said to be lean, greater than .450 volts are rich. The further from the .450 you get the richer or leaner a mixture is said to be. I like to think of .450 volts as a perfect mixture 14.7 AFR. Chemistry tells us that in order to combust 100% of an air & fuel mixture you need 14.7:1 ratio. That is 14.7 parts air to 1 part fuel. (different fuels will require different ratios, but this covers most of us here). When this mixture is achieved you have 100% combustion of the mixture. This is ideal for gas milage. If the mixture is said to be rich, you have not enough air and some of the fuel is left unburned. When your said to be lean, there is not enough fuel and air is passed through. The 02 sensor is calibrated to these different mixtures. As said above it reports these to the ECM, which adjusts it accordingly.
Onto what we all care about. Fuel milage, steady idles, quick throttle response, etc.
For emmission purposes cars are equipped with catalytic converters. To keep these converter happy, and allow them to do their magical chemical removal of harmful polutants they require frequent rich then lean spike in the exhaust stream. Understand that these spikes happen extremely quick several per second. The design of the algorithims of the ECM allow for this to happen.
The ECM is designed while in closed loop to toggle (switch) the Air/Fuel ratio from rich to lean. Tuners call this transitions. Transitions are reading from either side of the .450 voltage range. Follow me here. A GOOD healthy 02 will transition several times in a few seconds. ~15 times in 3-4 seconds. So in that 3-4 seconds. If one were to graph these values reported from the 02 you would see a very up and down spikey graph, with ~.450 as the average reading, or the midpoint of the high (rich) and low(lean) voltage readings. For all you mathmaticians out there, the midpoint or average would be .450, which we said earlier is ~14.7:1 AFR. In other words because the transitions happen sooooo quick and frequently, the resulting Air/fuel ration is basically 14.7:1. Which keeps the cats happy and gas milage optimum.
Ok, so let imagine what happens when a 02 is bad, wire rubbed through shorting the reading to the ECM, or is not getting hot enough? ( typical 02 MUST reach 650*F to operate correctly).
If your 02 sensor is bad then the ECM will take those readings for what they are worth. If they are stuck on the lean side of .450 volts, then the ECM is designed as I said before to add fuel to compensate the "lean" condition its being told. After it make a correction, it will add more fuel. See what is happening? There is no transition to rich. At some point, the ECM will quite its attempts, I do not know when this is. But what will result is a WAY WAY over mixture of fuel to air. Poor gas milage etc. Conversely, if its stuck on rich, the opposite will happen, fuel will be removed. Fortunately, as I said before, GM designed the ECM to recognize the fact that the transitions are not happening and to stop the trimming process to keep us from ruining our engines. However they did not incorporate a service engine light to tell us the sensor is dead. If you remove the sensor, it will trip a code, but I have never read/see a check engine light from a dead sensor. Wish they would have.
Another VERY common problem, has more to do with rough idle. Is the fact that many of us go with longtube headers, with ceramic coat. This causes another problem with the sensor. The sensor itself does not reach a hot enough temperature to properly work. That is why they make "heated" 02s. They are self heated to ensure that the 02 gets hot enough to properly function.
Enough of the "how it works stuff". How can you tell if your sensor is working? EASY and for 30 bucks you can monitor your 02s reading all the time.
Go to Wal-mart or equivalent store and buy a digital volt meter. Pick up some wire and some electrical connectors. This is about the easiest thing you will do to your car that will help you diagnose a problem. With the positive lead, connect it to your "information" wire off your 02 sensor. If you have a non-heated sensor, it will be the only wire on the sensor. Just get some of those connectors that allow you to side tap into wires. DO NOT CUT THE WIRE, the ECM still needs to get this signal too. Once you have the positive wire connected, then find a good ground for the negative lead. Any bolt will do on the frame/chassis. Make sure the wires are routed to the cabin of the car, and attach the volt meter to the leads. Set the scale of the meter to .xxx and start the car. After a short period of time you should see the Digital Volt Meter start to display random values. You should see while idling, values like ~.3XX then ~.7XX Then .2XX then .8XX then .2XX then .7XX.......you will think I lost my mind telling you to do this. But what you are seeing is exactly what the ECM is designed to do and what I said above. Its transitioning the mixture from lean (.3xx) to rich (.7xx) then back again. So you know everything is working properly.
If the reading is pretty steady with only small changes, then you have a problem. You should barely be able to keep up with reading the diplay and there should be large changes in the values, as shown in the paragraph above. If they are not acting like I say above, then put your foot on the gas peddle (Car in PARK) and give it some gas, to raise the RPMs about 1000. If then the sensor takes off and does as I say above, its just not getting hot enough. In which case you need to get a heated sensor (~50 bucks). What is happening is at idle the gasses of the exhaust are able to cool enough before hitting the o2, when you rev the motor the gasses speed up and reach the 02 quicker and at hotter temps. This is not a big deal, just get a heated sensor.
Ok, now you have the whole picture as to why a 02 is sooooooooo VERY VERY important to these cars. If its dead you throw the ECM into a blind scenerio where it can't adjust your fuel levels properly.
Wide open throttle is a whole nothing topic, so just keep your questions focused on idle/part throttle operation should you have any.
I SERIOUSLY hope that people will take the time to do this. Its VERY helpful to have this at your disposal. It will help you understand not only how the ECM is working, but as time passes and the sensor goes bad, you will be able to quickly detect it getting "lazy". The cost to do this is minimal, and with costs of fuel, will pay for itself in about 2 tanks of fuel. There is no excuse not to get this done. If you have a scanner you already can monitor what is happening. I have tuned two cars in the past month in person, and both of these cars had (1) a dead o2 sensor (2) the other had a lazy sensor at idle, but the latter of the two is not as serious. But still needs to be corrected.
If you would do the DVM trick, and see good transitions, and still be experiencing problems, its more than possible to have a short between where you tied into the 02s wire, and the ECM. If that happens one should then find the wire that goes into the ECM, from the 02 and connect into it right before the ECM as close as possible. If the reading are good close to the sensor, but bad near the ECM, you have a wire that is grounded out somewere between. In which case its probably easiest to just run a new wire to the o2 for the ECM to use.
I seriously hope that people read this and do as I say. Especially if your having rough idles. Poor gas milage etc. Its will take about 1 hour to do and will like I said pay for itself in no time. Not to mention my hands from typing are killing me and I hope this wasn't all in vein. :D :thumbs:
One of the mods, can you make this a tech note. Thanks!
:cheers: :cheers: :cheers: :cheers:
[Modified by ski_dwn_it, 9:58 AM 10/20/2003]
[Modified by ski_dwn_it, 9:59 AM 10/20/2003]
[Modified by ski_dwn_it, 10:05 AM 10/20/2003]
I have been talking with MANY people via email/phone/IM in regards to their setups. It seems that many of these people are experiencing roughly the same problems. Rough idles, poor gas milage, black smoke from the exhaust, ect.
These problems all seem to be linked to one common problem. Bad or lack of O2 sensors readings.
Once you understand how the ECM system works, you will realize that the 02 sensor is the #1 sensor that can make or break you.
Lets look at it in more detail. The ECM relies on feedback from the 02 sensor in order to correctly adjust fuel trims. This is a process that happens many times a second. The 02 monitors the exhaust gases and feeds the ECM information on the mixture. If the reading are lean, then the ECM will add fuel to the injectors trim to bring it to rich.
A key part of understanding how the system is suppose to work, is understanding what the 02 sensor telling the ECM with its readings.
A little information on the 02 sensor itself: The oxygen sensor itself is designed to generate a voltage based on the combustion mixture present in the exhaust system. To the 02 sensor itself the mixture this is either a rich mixture or a lean mixture. The o2 sensor was designed to be nothing more than a switch. Low readings less than .450 as said to be lean, greater than .450 volts are rich. The further from the .450 you get the richer or leaner a mixture is said to be. I like to think of .450 volts as a perfect mixture 14.7 AFR. Chemistry tells us that in order to combust 100% of an air & fuel mixture you need 14.7:1 ratio. That is 14.7 parts air to 1 part fuel. (different fuels will require different ratios, but this covers most of us here). When this mixture is achieved you have 100% combustion of the mixture. This is ideal for gas milage. If the mixture is said to be rich, you have not enough air and some of the fuel is left unburned. When your said to be lean, there is not enough fuel and air is passed through. The 02 sensor is calibrated to these different mixtures. As said above it reports these to the ECM, which adjusts it accordingly.
Onto what we all care about. Fuel milage, steady idles, quick throttle response, etc.
For emmission purposes cars are equipped with catalytic converters. To keep these converter happy, and allow them to do their magical chemical removal of harmful polutants they require frequent rich then lean spike in the exhaust stream. Understand that these spikes happen extremely quick several per second. The design of the algorithims of the ECM allow for this to happen.
The ECM is designed while in closed loop to toggle (switch) the Air/Fuel ratio from rich to lean. Tuners call this transitions. Transitions are reading from either side of the .450 voltage range. Follow me here. A GOOD healthy 02 will transition several times in a few seconds. ~15 times in 3-4 seconds. So in that 3-4 seconds. If one were to graph these values reported from the 02 you would see a very up and down spikey graph, with ~.450 as the average reading, or the midpoint of the high (rich) and low(lean) voltage readings. For all you mathmaticians out there, the midpoint or average would be .450, which we said earlier is ~14.7:1 AFR. In other words because the transitions happen sooooo quick and frequently, the resulting Air/fuel ration is basically 14.7:1. Which keeps the cats happy and gas milage optimum.
Ok, so let imagine what happens when a 02 is bad, wire rubbed through shorting the reading to the ECM, or is not getting hot enough? ( typical 02 MUST reach 650*F to operate correctly).
If your 02 sensor is bad then the ECM will take those readings for what they are worth. If they are stuck on the lean side of .450 volts, then the ECM is designed as I said before to add fuel to compensate the "lean" condition its being told. After it make a correction, it will add more fuel. See what is happening? There is no transition to rich. At some point, the ECM will quite its attempts, I do not know when this is. But what will result is a WAY WAY over mixture of fuel to air. Poor gas milage etc. Conversely, if its stuck on rich, the opposite will happen, fuel will be removed. Fortunately, as I said before, GM designed the ECM to recognize the fact that the transitions are not happening and to stop the trimming process to keep us from ruining our engines. However they did not incorporate a service engine light to tell us the sensor is dead. If you remove the sensor, it will trip a code, but I have never read/see a check engine light from a dead sensor. Wish they would have.
Another VERY common problem, has more to do with rough idle. Is the fact that many of us go with longtube headers, with ceramic coat. This causes another problem with the sensor. The sensor itself does not reach a hot enough temperature to properly work. That is why they make "heated" 02s. They are self heated to ensure that the 02 gets hot enough to properly function.
Enough of the "how it works stuff". How can you tell if your sensor is working? EASY and for 30 bucks you can monitor your 02s reading all the time.
Go to Wal-mart or equivalent store and buy a digital volt meter. Pick up some wire and some electrical connectors. This is about the easiest thing you will do to your car that will help you diagnose a problem. With the positive lead, connect it to your "information" wire off your 02 sensor. If you have a non-heated sensor, it will be the only wire on the sensor. Just get some of those connectors that allow you to side tap into wires. DO NOT CUT THE WIRE, the ECM still needs to get this signal too. Once you have the positive wire connected, then find a good ground for the negative lead. Any bolt will do on the frame/chassis. Make sure the wires are routed to the cabin of the car, and attach the volt meter to the leads. Set the scale of the meter to .xxx and start the car. After a short period of time you should see the Digital Volt Meter start to display random values. You should see while idling, values like ~.3XX then ~.7XX Then .2XX then .8XX then .2XX then .7XX.......you will think I lost my mind telling you to do this. But what you are seeing is exactly what the ECM is designed to do and what I said above. Its transitioning the mixture from lean (.3xx) to rich (.7xx) then back again. So you know everything is working properly.
If the reading is pretty steady with only small changes, then you have a problem. You should barely be able to keep up with reading the diplay and there should be large changes in the values, as shown in the paragraph above. If they are not acting like I say above, then put your foot on the gas peddle (Car in PARK) and give it some gas, to raise the RPMs about 1000. If then the sensor takes off and does as I say above, its just not getting hot enough. In which case you need to get a heated sensor (~50 bucks). What is happening is at idle the gasses of the exhaust are able to cool enough before hitting the o2, when you rev the motor the gasses speed up and reach the 02 quicker and at hotter temps. This is not a big deal, just get a heated sensor.
Ok, now you have the whole picture as to why a 02 is sooooooooo VERY VERY important to these cars. If its dead you throw the ECM into a blind scenerio where it can't adjust your fuel levels properly.
Wide open throttle is a whole nothing topic, so just keep your questions focused on idle/part throttle operation should you have any.
I SERIOUSLY hope that people will take the time to do this. Its VERY helpful to have this at your disposal. It will help you understand not only how the ECM is working, but as time passes and the sensor goes bad, you will be able to quickly detect it getting "lazy". The cost to do this is minimal, and with costs of fuel, will pay for itself in about 2 tanks of fuel. There is no excuse not to get this done. If you have a scanner you already can monitor what is happening. I have tuned two cars in the past month in person, and both of these cars had (1) a dead o2 sensor (2) the other had a lazy sensor at idle, but the latter of the two is not as serious. But still needs to be corrected.
If you would do the DVM trick, and see good transitions, and still be experiencing problems, its more than possible to have a short between where you tied into the 02s wire, and the ECM. If that happens one should then find the wire that goes into the ECM, from the 02 and connect into it right before the ECM as close as possible. If the reading are good close to the sensor, but bad near the ECM, you have a wire that is grounded out somewere between. In which case its probably easiest to just run a new wire to the o2 for the ECM to use.
I seriously hope that people read this and do as I say. Especially if your having rough idles. Poor gas milage etc. Its will take about 1 hour to do and will like I said pay for itself in no time. Not to mention my hands from typing are killing me and I hope this wasn't all in vein. :D :thumbs:
One of the mods, can you make this a tech note. Thanks!
:cheers: :cheers: :cheers: :cheers:
[Modified by ski_dwn_it, 9:58 AM 10/20/2003]
[Modified by ski_dwn_it, 9:59 AM 10/20/2003]
[Modified by ski_dwn_it, 10:05 AM 10/20/2003]
10-20-2003, 10:08 AM
#3
Race Director
Re: Please Read... (ski_dwn_it)
Hey Jesse, what about two O-2 sensors, one on each side, does this help any with giving the ECM better info on the average?
I have read where some have put one O-2 into each exhaust manifold/header and wondered if there is a benefit to this.
I have read where some have put one O-2 into each exhaust manifold/header and wondered if there is a benefit to this.
10-20-2003, 10:15 AM
#4
Former Vendor
Thread Starter
Re: Please Read... (ld85)
ID85, Not really, since the ECM is making the same corrections to to both banks of injectors , based on the one reading.
If you had a DFI (aftermarket) tuning system, you can actually tune easdh cylinder differently. In whick case, you would need an 02 in each primary tube off each cylinder. That is if you were not going to make global changes to all cylinders like our cars do.
That might have been a little confusing the way I answered your question, but really there is no need to have more than 1 o2.
:cheers:
If you had a DFI (aftermarket) tuning system, you can actually tune easdh cylinder differently. In whick case, you would need an 02 in each primary tube off each cylinder. That is if you were not going to make global changes to all cylinders like our cars do.
That might have been a little confusing the way I answered your question, but really there is no need to have more than 1 o2.
:cheers:
10-20-2003, 10:18 AM
#5
Team Owner
Re: Please Read... (ski_dwn_it)
Wow thanks I never knew how the 02 sensor worked never mind how to test if it's working properly. :cool: :cheers: :cheers: :cheers:
10-20-2003, 10:20 AM
#6
Safety Car
Re: Please Read... (ski_dwn_it)
Good info,
So for us with duel O2 sensors I supose we will need to have another set of wires and chck the second O2 sensor as well. I noticed when pulling my plugs yesterday that one bank of plugs apears to be running much richer than the other so I think this will be a good check for me. I have injector problems right now but the new injectors should be here today and then I will run the test on both O2 sensors to see whats up.
So for us with duel O2 sensors I supose we will need to have another set of wires and chck the second O2 sensor as well. I noticed when pulling my plugs yesterday that one bank of plugs apears to be running much richer than the other so I think this will be a good check for me. I have injector problems right now but the new injectors should be here today and then I will run the test on both O2 sensors to see whats up.
10-20-2003, 11:10 AM
#8
Drifting
Re: Please Read... (84LT1)
I've never heard the "keeping the cat happy" function before. I'm not so I sure this is true. The cat will do it's thing if it gets hot enough, enough air, doesn't get poisoned (lead), and it doesn't melt (lean) or cool down (rich). (If the engine stays in the Stoch window 14.7:1, the converter is happy.)
The toggle action of the O2 sensor has to do w/ basic feedback loop operation and very narrow band O2.
If the O2 sensor ever gets grounded while working (warm), it will kill it. If the sensor ever gets an ohm meter across it, it will kill it. I.e. Never Ohm out an O2 sensor. If the inner ceramic cracks,.. the sensor is history. (Don't drop it.)
BTW They have an 18mmx1.5 thread.
From Bosch (leading maker of O2 sensors): http://www.boschusa.com/AutoParts/FAQs/OxygenSensors
Just adding a couple pennies to the conversation.
Nice write up. Thanks for doing it.
[Modified by ZylaRace, 11:13 AM 10/20/2003]
The toggle action of the O2 sensor has to do w/ basic feedback loop operation and very narrow band O2.
If the O2 sensor ever gets grounded while working (warm), it will kill it. If the sensor ever gets an ohm meter across it, it will kill it. I.e. Never Ohm out an O2 sensor. If the inner ceramic cracks,.. the sensor is history. (Don't drop it.)
BTW They have an 18mmx1.5 thread.
From Bosch (leading maker of O2 sensors): http://www.boschusa.com/AutoParts/FAQs/OxygenSensors
Just adding a couple pennies to the conversation.
Nice write up. Thanks for doing it.
[Modified by ZylaRace, 11:13 AM 10/20/2003]
10-20-2003, 12:06 PM
#10
Former Vendor
Thread Starter
Re: Please Read... (ZylaRace)
I've never heard the "keeping the cat happy" function before. I'm not so I sure this is true. The cat will do it's thing if it gets hot enough, enough air, doesn't get poisoned (lead), and it doesn't melt (lean) or cool down (rich). (If the engine stays in the Stoch window 14.7:1, the converter is happy.)
The toggle action of the O2 sensor has to do w/ basic feedback loop operation and very narrow band O2.
[Modified by ZylaRace, 11:13 AM 10/20/2003]
The toggle action of the O2 sensor has to do w/ basic feedback loop operation and very narrow band O2.
[Modified by ZylaRace, 11:13 AM 10/20/2003]
The Oxidization Catalyst
The oxidation catalyst is the second stage of the catalytic converter. It reduces the unburned hydrocarbons and carbon monoxide by burning (oxidizing) them over a platinum and palladium catalyst. This catalyst aids the reaction of the CO and hydrocarbons with the remaining oxygen in the exhaust gas. For example:
2CO + O2 => 2CO2
But where did this oxygen come from?
The Control System
The third stage is a control system that monitors the exhaust stream, and uses this information to control the fuel injection system. There is an oxygen sensor mounted upstream of the catalytic converter, meaning it is closer to the engine than the converter is. This sensor tells the engine computer how much oxygen is in the exhaust. The engine computer can increase or decrease the amount of oxygen in the exhaust by adjusting the air-to-fuel ratio. This control scheme allows the engine computer to make sure that the engine is running at close to the stoichiometric point, and also to make sure that there is enough oxygen in the exhaust to allow the oxidization catalyst to burn the unburned hydrocarbons and CO.
Also I have never heard of an ohm meter ruining an O2 sensor, nor did my o2 sensor get ruined when my wire accidentially got shrted on the header pipe last year during a 2 hour trip to the track. I noticed it right away on my WB that the AFR was way off 14.7, knew it was o2 sensor related, so I crawled down there upon arriveal at the track, found the wire melted to the collector. peeled it off, wrapped it with some elctrical tape, raced the rest of the night, got home put it up on a lift. Cut out the back section and solder it bac together. That was ~15 months ago. I have not had a problem with it since :skep:
:lurk:
10-20-2003, 01:06 PM
#12
Safety Car
Member Since: Sep 2003
Location: Charleston SC
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Re: Please Read... (ski_dwn_it)
Is fuel trim included in the MPG calculations for the dash fuel milage indicator? I'm reading around 20 but actually getting around 12. I've been searching for a leak without success.
10-20-2003, 01:15 PM
#13
Former Vendor
Thread Starter
Re: Please Read... (rkessel)
Rkessel,
Yeah your trims etc all enter into your dashes MPG. If you have or someone else put aftermarket injectors in the car, then the MPG is not right. I highly suggest that you heed the warning signs of poor gas mileage and do what I say here in the post.
You should be getting MUCH MUCH better gas milage than you are. Corkvette monitored his gas usage on his last long trip. He got 22 MPH, not by the gage, but with the old fashion way, fill it record milage. Travel, fill it, record milage and figure it out that way. That is in a car that just hit 10.94 through the 1/4 mile!
Anyways, I am going to search to see if I can find the correct wire, and location on the ECM, as really I should say that you should as a first check, do the T in, near the ECM. That way your incorporating the entire line out to the sensor as well. Then if you have a problem, move it down to towards the sensor to eliminate the possibility that the problem could be just in the wiring. I fear the way I have it laid out above, people will get a good reading at the sensor, and then assume that the wiring is ok. If checked closer to the ECM, it would force them to move down the line.
Thanks for all the comments!
:cheers:
Yeah your trims etc all enter into your dashes MPG. If you have or someone else put aftermarket injectors in the car, then the MPG is not right. I highly suggest that you heed the warning signs of poor gas mileage and do what I say here in the post.
You should be getting MUCH MUCH better gas milage than you are. Corkvette monitored his gas usage on his last long trip. He got 22 MPH, not by the gage, but with the old fashion way, fill it record milage. Travel, fill it, record milage and figure it out that way. That is in a car that just hit 10.94 through the 1/4 mile!
Anyways, I am going to search to see if I can find the correct wire, and location on the ECM, as really I should say that you should as a first check, do the T in, near the ECM. That way your incorporating the entire line out to the sensor as well. Then if you have a problem, move it down to towards the sensor to eliminate the possibility that the problem could be just in the wiring. I fear the way I have it laid out above, people will get a good reading at the sensor, and then assume that the wiring is ok. If checked closer to the ECM, it would force them to move down the line.
Thanks for all the comments!
:cheers:
10-20-2003, 01:23 PM
#14
Race Director
Re: Please Read... (ski_dwn_it)
Hey Ski, Copy this great article you wrote and put it in the tech tips so we don't lose it. We appreciate you time and effort. Here's to you :cheers:
10-20-2003, 01:38 PM
#15
Burning Brakes
Re: Please Read... (Strick)
Is there any way the moderator can lock this post up at the top? then it will be around here for long term, and people can use it as a reference in the tech. section here
10-20-2003, 01:58 PM
#17
Former Vendor
Thread Starter
Re: Please Read... (Jay 383)
Just as I did with LPE, I'll send the car to you Jesse, and you let me know when it's perfect LOL.
:jester
:jester
10-20-2003, 02:09 PM
#18
Team Owner
Re: Please Read... (ski_dwn_it)
so does my 93 still need both O2's or can i replace on ewith a wide band?
10-20-2003, 02:12 PM
#19
Race Director
Member Since: Sep 2000
Location: The Top of Utah
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Re: Please Read... (ski_dwn_it)
Great article, Jessie. I just know this is part, if not all, of my problem. The cause, I believe is an oil contaminated O2. It runs "pig rich" and as you suggested, no codes. Maybe a new one will stay clean enough to get through a smog test. Then, it's time to eliminate the source of the problem. Thanks, and...
RACE ON!!!
RACE ON!!!
10-20-2003, 02:15 PM
#20
Melting Slicks
Member Since: Mar 2001
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Cruise-In IV Veteran
Cruise-In V Veteran
St. Jude Contributor
Re: Please Read... (ski_dwn_it)
Excellent write up. Thanks! :cheers:
Just one clarification. The car should be in PARK when I rev the engine? :lol: :yesnod:
Thanks again.
Just one clarification. The car should be in PARK when I rev the engine? :lol: :yesnod:
Thanks again.