Looking for Tuner for 95 lt1 mesa az
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I think he pmd me, not 100%. My problem is emissions, I'm not sure how someone could tune for that without having the car? I would love to go torqhead but funds limit that, if i had the funds it would go for a 5.3 swap lol.
I have two different tunes, one for emissions and one for performance, usually the customer has either a spare pcm or software to interchange the tunes, I can do a performance emissions tune, but it would leave some horsepower on the table.
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Can anybody look at these numbers and tell me what they see here? I have a good idle until it goes into closed loop, then surges for a few then goes away for the most part, I'm really confused by it. What i saw was the iac bouncing around but the iac itself ohmed within spec and i cleaned the housing. Any help would be great. One might be uploaded twice.
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Rebuilt stock with pacesetter shorties with magnaflow catback and welded in New cat. Falling with a high hydrocarbons, 1.06, limit is .80. Nox was at 2.11, limit is 2.00. This is after i wired the air pump to run at all times just to try and get it to pass. Before the numbers were really high, i just don't have them at the moment. I did warranty the cat today though so I'm hoping that's where my problem lies but won't know until tomorrow. Right now was trying to see if anyone could help out with the idle issue, it has a new opti, I've tried 3 different ones to make sure that wasn't the issue.
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Verdad Gallardo Usually, faulty O2 sensors cause issues when the car goes into closed loop as the computer tries to maintain Stoich. You might want to try logging/graphing the O2 sensor readings on both banks. It would cause the surging as the computer tries to correct the A/F ratio which could lead to the IAC moving to keep the car running. That is where I would look first.
Check your intake and MAF for leaks between the MAf and throttle body. Also, if you are driving it around make sure you datalog it and watch your short and long term fuel trims. The fuel trims will point you to the right direction.
High NOx and High HC indicate a lean mixture. Somehow, unmetered air is entering the combustion chamber. Or, injectors aren't firing enough fuel. Your O2s are pegged lean in the snapshots you attached, but since narrow band O2's will bounce back and forth as motor adjusts mixture, you would have to say if they bounce back and forth or stay pegged. What is interesting is that your LTFT's and STFT's are pretty much all middle of the road, but this is only one motor condition, without a log its hard to say definitively what the car is seeing. I can only echo Nostang that a log here is critical, one snapshot makes this difficult. Lastly, I noticed that your IACs are pegged low with really no wiggle to go lower. Ideally these hover around 32. This indicates either the IAC is stuck... or the ECU is trying to compensate for idle air coming from another location past the MAF (vacuum leak).
There is definitely air getting in somewhere, so I would start down that path way.
There is definitely air getting in somewhere, so I would start down that path way.
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Ok, first off, thanks for the replies and sorry i haven't got back sooner. It has a new maf and intake elbow and i can't find any leaks what so ever! I know the snap shots don't really tell the whole story, but yes the 02s move back and forth as they should, the iac is what is weird to me though, it moves up and down with the idle though. I got the thing to pass for right now though, i hooked the vacuum line straight from the intake to the egr valve and passed with flying colors, still have more investigating to do though. If and when i find the culprit I'll definitely post it.