service engine light?
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From: anderson sc
service engine light?
well yesterday i got my mccord power plates installed, which i like ALOT!! ran around with them open every once in a while. today i go to an autocross and make about 5 laps. fun stuff. had em open the whole time. i come home and start to clean my car up. cleaned up the greasy engine and all. and yea i hosed it down. but it ran fine. anyhow, after i got going down the road the SES light came on. i pull over and turn it off. after a few secs i turn it back on with no light and drive off. about 10 mins later it does it again and i restart it with it working fine. so what's the deal? is it my cutouts or me gettin the engine wet? anyhow it ran fine and i hope it dont come on again. ideas? :flag
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From: Athens AL
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Re: service engine light? (Clemson Vette)
You didnt do too bad at the autox.
You got to pull the codes though.
You got to pull the codes though.
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From: anderson sc
Re: service engine light? (vader86)
which autocross are you talking about? the one at the airport or at clemson? and thanks but i sucked at the airport. and found out that it isnt the water, cause it's 2 days later and still does it. how do i pull the codes? thanks for the help and please get me thru this. runs fine but i dont wanna hurt the car. i highly recommend the cutouts too. :D
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From: Athens AL
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Re: service engine light? (Clemson Vette)
The airport, i was there. If you havent done the Upper Limit Low Speed Autox stuff before, you didnt do too bad. If you have, then you really did suck, the car shouldve gotten another 4sec off your times.
You can take it to autozone or a dealer and they can pull the codes if you dont have a scanner. However, if its still acting up days later, you may have hosed the Opti.
You can take it to autozone or a dealer and they can pull the codes if you dont have a scanner. However, if its still acting up days later, you may have hosed the Opti.
Heel & Toe
Joined: Jul 2003
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From: Austin TX
Re: service engine light? (Clemson Vette)
what year is your vette? If it is 94 or later you will need a scanner, if it is pre94, you can take a paper clip and jump the ALDL under the steering wheel and pull the codes. I am not sure of the exact pins to jump, I think it is A and B, it will be on one of the ends where there is a 2 contacts in a row, usually there is only one option. Turn key on and the check engine light will start flashing. It will flash a code 12 3 times (flash once, pause, flash twice) and then it will flash another code 3 times, count the flashes. It will flash 12 again once it is doen. My guess would be TPS sensor, got some water in it. Hope this helps. RD
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From: anderson sc
Re: service engine light? (94vettin)
ok great. first of all, that was my 4th time auto Xing ever so thanks. and i'm glad to hear that it isnt my super loud cutouts making the code junk happen. i'll get it read tomorrow. but if it is the opti, how can i know? i thought that a 95 had a vent that allowed the water to drain out and so on? is there a way to fix it? how envolved? i'll get back with you all tomorrow and tell ya what the scanner dude says. thanks for the help. i really hope that the opti isnt bad. i only got 9k on this one. that would suck. :rant:
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From: anderson sc
Re: service engine light? (Clemson Vette)
ok well heres the deal. first of all, taker vader. do you know anywhere round here that can scan my car? autozone in anderson said they can only do obd2 cars. so i'm still workin to get that done. and do these places charge to scan it? now about that light. as i said it comes on at random. but i heard talk that it could be the knock sensor going off cause of all the racket i'm making with the cutouts. that true? how would i fix it if it were the case? and exactly how could me wetting the opti hurt it if it still runs like a banshee? i'm not doubting you fellas, but i just wanna get my ducks in a row. thanks :flag
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From: anderson sc
Re: service engine light? (Clemson Vette)
ok heres the deal. still cant get the car scanned cause i dont know where one is. but i did go and drive it tonight alot. drove with the cutouts closed and no light. once i open them it takes about 5 mins and then th elight comes on. it stays on till i restart the car. this happened twice, as in i went and drove with them shut. then i opened them and timed it. the third time i tried it i couldnt get it to light up. drove a long time and no light came on at all. i was thinkin it is the knock sensor saying that i'm knocking, from all the noise. has anyone at all ever had this happen to them? if so is there a way to deaden it of adjust the sensitivity? and do these symptoms still sound like opti problems to you people? thanks for the help. :cry :cry
Burning Brakes
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From: Whittier ca
Re: service engine light? (Clemson Vette)
Clemson - you still have not told us what year. If you have OBD1, jump a-b terminals (the 2 extreme right on the block under the steering wheel) As posted before, count the flashes of the SES light. 1-pause-2 will come up 3 times. Then count the flashes. Each error code will flash 3 times, then move on to the next error code. When all errors have flashed, the 1-pause-2 will flash again 3 times. Hopefully, you have written them down so you can check in the book or check with AutoZone for the corresponding problems.
Good Luck - let us know.
Subman
(Kinda wish we had a place to run out here that wasn't an arm and leg, just to see if we still had it)
Good Luck - let us know.
Subman
(Kinda wish we had a place to run out here that wasn't an arm and leg, just to see if we still had it)
Heel & Toe
Joined: Jul 2003
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From: Austin TX
Re: service engine light? (Clemson Vette)
if you have a 95 you have the obd2 connector with obd1 data. I have the same thing on my 94 and I went ahead and bought a EZlink scanner that will do obd1 and obd2. 94 and 95 were trial years and there is very few cars that fall into this category. If you are not willing to spend min 200 on a scanner, then it might be worth your while to take it to a shop and have them pull the codes. My guess is that you will need to have a hyper-program to keep the SES light off with your cut offs. The computer is looking for a certain reading on your O2 sensor and it is going to try and compensate up to a point, then the computer will go into OPEN LOOP and use preset readings. Being that it iruns fine without the cutoffs, I would guess that is what is going on. RD
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Re: service engine light? (Clemson Vette)
You may need a LT4 Knock module, i dont think its the O2 sensor.
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From: anderson sc
Re: service engine light? (vader86)
ok finally got some work done on it. i found a guy to scan it for $35, dang i need to buy one of those. he said that the only code he could find was for a right o2 sensor, he didnt say what was up but that it was the only thing it read. but like i said, last night when driving it for the 3rd round, i couldnt get the light on. so do you think it corrected itself? can it do that? and i had to move that right o2 sensor from about 16 inches down the exhaust pipe to right after the collector. does the location of the sensor make a difference?, i had them moved so they would be able to read even with the cutouts open. and should the sensor being so close to the manifold make a difference? will another o2 sensor stand up to the noise? thanks so much for the help, and vader, i'll keep that lt4 knock sensor in mind if the prob persists. i take it that it can handle more noise? can i get it at autozone etc? thanks again guys, yall saved my butt. :party:
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From: Athens AL
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Re: service engine light? (Clemson Vette)
If you moved the O2 sensor along the pipe, Id like to see before and after pics of where its mounted. The location does make a difference, its supposed to measure a certain temperature.
If the ECM doesnt detect anything wrong with the O2 sensor after driving, it can turn off the SES light.
Its not the noise that is hurting the sensor, its the heat in the exhaust its supposed to read. With the cutouts open, there is much less heat buildup and its throwing off your readings, which will kill your gas mileage with the cutouts open. The ECM will think it needs to richen the mixture up, to build up more heat.
If the ECM doesnt detect anything wrong with the O2 sensor after driving, it can turn off the SES light.
Its not the noise that is hurting the sensor, its the heat in the exhaust its supposed to read. With the cutouts open, there is much less heat buildup and its throwing off your readings, which will kill your gas mileage with the cutouts open. The ECM will think it needs to richen the mixture up, to build up more heat.
