Good compression test. Should I do a leak down?
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Burning Brakes
Joined: Feb 2004
Posts: 1,069
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From: Sanford NC
Good compression test. Should I do a leak down?
I thought I may had hurt my stock short block so I did a compression test today. All the cylinders came in inbetween 203-209 cranking compression. The drivers side was a little lower than the pass side. Should I do a leak down test as well? Can a leak down test show me any thing the compression test wouldn't? I am pretty sure the short block is not my problem any more. The thing just has not run right since the Meth kit was put on. I am going to disconnect the power to the kit and see what happens.
Brett
Brett
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 1,069
Likes: 8
From: Sanford NC
I just retruned from over seas on Sunday so I have not had a chance to put the WB on it. I think with tax returns I am going to buy the EFI live kit with the LC-1. Now that I know it isn't my short block. I agree that it must be going pig rich. I did dyno tune it to where I wanted it but on the street it has never run correct. I keep getting P0172 and 175 codes. Bank one and two rich after about 20min of steady cruise. I put a scanner on it just driving around and my LTFT's never go more than -5 but I didn't get to do a steady cruise. I changed plugs and that didn't seem to help. I was going to change the wires next the coil packs but I think the problem is the meth. I will disconnect it today and see what happens. It just starts to break up under power. It really feals like an ignition problem. Could be bad spring? All the mods on the car only have 6,000 miles on them.
Brett
Brett
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Joined: May 2002
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From: waterloo ontario
St. Jude Donor '08
That breaking up is the car going pig rich-depending on your tune the car will go at least a full point richer. My car did the exact same thing when hooked up the meth-as soon as boost came in it fell flat on it's face. Hook up the wideband and log-you'll see it's probably dropping off beyond 10.1.
Safety Car
Joined: Jul 2005
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From: Vancouver WA
If you want more power out of the Meth, you will have to lean your fuel, and maybe even run a little more timing. Otherwise, it's just a safety net, and it can cause a power loss if not tuned for it.
Meth is a little slower burning, so it will need more timing to make optimum peak cylinder pressure at the right crank angle. I think this is where a Dyno can come in handy.
Meth is a little slower burning, so it will need more timing to make optimum peak cylinder pressure at the right crank angle. I think this is where a Dyno can come in handy.
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I just retruned from over seas on Sunday so I have not had a chance to put the WB on it. I think with tax returns I am going to buy the EFI live kit with the LC-1. Now that I know it isn't my short block. I agree that it must be going pig rich. I did dyno tune it to where I wanted it but on the street it has never run correct. I keep getting P0172 and 175 codes. Bank one and two rich after about 20min of steady cruise. I put a scanner on it just driving around and my LTFT's never go more than -5 but I didn't get to do a steady cruise. I changed plugs and that didn't seem to help. I was going to change the wires next the coil packs but I think the problem is the meth. I will disconnect it today and see what happens. It just starts to break up under power. It really feals like an ignition problem. Could be bad spring? All the mods on the car only have 6,000 miles on them.
Brett
Brett
For you to get the codes you are seeing the car needs to have fuel trims that are way off. That would not be caused by adding meth, that is in your base tune where the meth would not be used. (non boost)
From there your WOT setting are also probably too rich from adding the meth without a tune. Basically you have two different tuning issues that are easy to correct.
Melting Slicks
Joined: Sep 2002
Posts: 3,064
Likes: 95
From: MI
The answer to one of your original question is yes: a leakdown test can tell you things that a compression test won't. I learned that the hard way when I bought my viper. I ended up having to do a minor refresh because of it: compression test ok, leak down test not so good
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Melting Slicks
Joined: Mar 2003
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From: Macomb MI
For you to get the codes you are seeing the car needs to have fuel trims that are way off. That would not be caused by adding meth, that is in your base tune where the meth would not be used. (non boost)
From there your WOT setting are also probably too rich from adding the meth without a tune. Basically you have two different tuning issues that are easy to correct.
From there your WOT setting are also probably too rich from adding the meth without a tune. Basically you have two different tuning issues that are easy to correct.
Other than that, Doug covered the obvious.
Also, Is this the car that blew the dipstick? Make sure you vented the crankcase
Phil
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 1,069
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From: Sanford NC
Thanks for the responses guys.
I did have the car tuned for the meth. But we turned the dial a little more for added safety after the last pull. It ran fine on the dyno. But during and after the hour and a half drive home it started acting funny. It is chunky if that makes since. It doesn't rev up quickly. It is not snappy like before. The meth I got from my tuner has a cherry smelling additive that I could smell all the way home. (not under boost) Plus I was going through a tank of meth in a week with no WOT pulls. No leaks. At the track it started running worse and ticking under power in 4th. Like it was pig rich. I think the meth is leaking into the intake system. I have the anti syphon valve in there. I am going to check the wireing. Some thing is up. I just have to narrow it down. Process of elimination sucks but I am to that point. I guess I will do a leak down test as well. Thanks again guys for the ideas.
As far as the dip stick. It is lifting it out a little now. I have the ECS breather, a small breather on the tube that originaly went to the air filter and the manifold vent is now hooked to the air filter. The dip stick lift was why I thought I was getting blow by originaly.
Brett
I did have the car tuned for the meth. But we turned the dial a little more for added safety after the last pull. It ran fine on the dyno. But during and after the hour and a half drive home it started acting funny. It is chunky if that makes since. It doesn't rev up quickly. It is not snappy like before. The meth I got from my tuner has a cherry smelling additive that I could smell all the way home. (not under boost) Plus I was going through a tank of meth in a week with no WOT pulls. No leaks. At the track it started running worse and ticking under power in 4th. Like it was pig rich. I think the meth is leaking into the intake system. I have the anti syphon valve in there. I am going to check the wireing. Some thing is up. I just have to narrow it down. Process of elimination sucks but I am to that point. I guess I will do a leak down test as well. Thanks again guys for the ideas.
As far as the dip stick. It is lifting it out a little now. I have the ECS breather, a small breather on the tube that originaly went to the air filter and the manifold vent is now hooked to the air filter. The dip stick lift was why I thought I was getting blow by originaly.
Brett
Last edited by PRAY; Jan 24, 2007 at 12:30 PM.
Thread Starter
Burning Brakes
Joined: Feb 2004
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From: Sanford NC
Here is the update. I talked with Julio about my meth issues and we decided to electricly shut the system off and see if meth was still being consumed by the engine. I initialy thought it was because it was running the same but after two days of driving I could see no dicernable differences in the level of meth in the tank. So this morning I replaced the plug wires and the car seems to be running alot better. Not perfect but no more missing. I did find that the power wire to the MAP sensor on the alky kit was run straight into the 12v IGN source and not through the power distribution block. I corrected that. I don't know if it will make a difference or not. No I have to fine tune the meth again since I touched some of the dials. I am still going to do a leak down test for my on gratification and peace of mind. I am also going to swap out coil packs from a friends car and see if that cleans the revs up any. I will make another trip to the track Sunday and see what I come up with. I think I am going to make two passes with out the meth and a couple with to try to fine tune it. It will make a nice comparison any way. Thanks for the help guys.
Brett
Brett
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^^^^^
Ummmm, I thought the MAP sensor wanted 5V, not 12V. If it was run straight to 12V the MAP sensor may be FUBAR. Julio would know for sure as I am certain other people have done this before. Or maybe it does want 12v, I don't remember.
BTW, if it did want 5v and got 12v... your problem very well may have been that the kit was spraying when it should not have. I am sure the output signal from the MAP sensor would be funky if it was getting a different voltage than it wanted to run on.
Ummmm, I thought the MAP sensor wanted 5V, not 12V. If it was run straight to 12V the MAP sensor may be FUBAR. Julio would know for sure as I am certain other people have done this before. Or maybe it does want 12v, I don't remember.
BTW, if it did want 5v and got 12v... your problem very well may have been that the kit was spraying when it should not have. I am sure the output signal from the MAP sensor would be funky if it was getting a different voltage than it wanted to run on.
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 1,069
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From: Sanford NC
That's a good point Diynoob. I didn't even think about that. I will call Julio and ask him. I am pretty sure from reading the instructions that it does only want 5v. I don't know if that is just a 5v sensor or it can only take a 5v power source. I guess that is what you get when you don't install a part on your own. I should have learned in the past. But simple mistakes seem to happen when people know what they are doing.
Last edited by PRAY; Jan 26, 2007 at 08:01 PM.
Thread Starter
Burning Brakes
Joined: Feb 2004
Posts: 1,069
Likes: 8
From: Sanford NC
Do you think the MAP is jacked? The system seemed to be working when I turned it back on. It was fat as hell and falling on its face when it turned on. I adjusted it a little. I will mess with it tomorrow before I go to the track. I just want my solid 10 sec pass at 135 and I am done. I am just about sick of this car right now.
On another note Arun I am excited for you man. It looks like your stuff is coming together nice. I can't wait to hear some numbers. I want to come to Virginia so bad. But family first always. Some one needs to make a good video out of the event. I would pay for a perfessionaly done vid.
Brett
On another note Arun I am excited for you man. It looks like your stuff is coming together nice. I can't wait to hear some numbers. I want to come to Virginia so bad. But family first always. Some one needs to make a good video out of the event. I would pay for a perfessionaly done vid.
Brett
Safety Car
Joined: May 2002
Posts: 3,615
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From: waterloo ontario
St. Jude Donor '08
Do you think the MAP is jacked? The system seemed to be working when I turned it back on. It was fat as hell and falling on its face when it turned on. I adjusted it a little. I will mess with it tomorrow before I go to the track. I just want my solid 10 sec pass at 135 and I am done. I am just about sick of this car right now.
On another note Arun I am excited for you man. It looks like your stuff is coming together nice. I can't wait to hear some numbers. I want to come to Virginia so bad. But family first always. Some one needs to make a good video out of the event. I would pay for a perfessionaly done vid.
Brett
On another note Arun I am excited for you man. It looks like your stuff is coming together nice. I can't wait to hear some numbers. I want to come to Virginia so bad. But family first always. Some one needs to make a good video out of the event. I would pay for a perfessionaly done vid.
Brett
Thanks for the props bro-it's gonna be fun-You know that were testing in Maryland on the friday first-then heading to Virginia the next day. Then Earl's also setting up a an event in May.
You'll get your 10 with ease bro-if theres anything I can do to help just hollar bro.
