sqd
09-07-2010, 05:39 AM
First, a little story time, I'm sorry for writing so much, but there's alot of info of what I've done so far..
Relevant parts list to my problem:
- 1995 blacktop SR20DET, forged bottom end etc
- PowerFC w/ commander (no Datalogit though)
- HKS Stage 1 cams
- 850cc injectors
- 3" exhaust from the turbo, SSQV, 100-cell Catco cat, custom made exhaust manifold
- Walbro 255lph pump, EGR removed, Z32 MAF, FueLab 1:1 FPR
Car was built, dyno'd/mapped to just about 400 flywheel hp.
Installed the Catco cat before inspection, measured my emissions and they were good/passed. Then went on to recirculate the BOV.
Went and did the inspection, failed the emissions test. After that, noticed that my manifold was cracked, thought that was the problem, so gave the car to a shop for a custom manifold. Got the car back, measured again, still very bad emissions.
Now, I don't have a wideband O2, all I have is the Apex'i turbo timer that reads the stock O2 and calculates the AFR - now I know this is not precise at all, but so far it has given me an idea of what the AFR is, so it works for me at the moment. The idle AFR I had when i failed was between 12.6-13. So very rich.
So, then after some research I found the problem - the recirculation of the SSQV. Removed the recirc hose, plugged the recirc hole in the pipe between the MAF and the turbo with my hand, a friend checked the turbo timer - 14.1 steadily. Great, put the hose back on, drove home, came to the parking lot and my idle began to bounce/jump up and down, like a vacuum leak.
Video of the idling (it's not as bad right now, but still..)
sr20det idle Pictures, sr20det idle Images, sr20det idle Photos, sr20det idle Videos - Video - TinyPic - Free Image Hosting, Photo Sharing & Video Hosting (http://tinypic.com/player.php?v=2rcrj1x&s=7)
Didn't have time to do anything about it then, had to take first things first - went and got myself a replacement pipe for the one between the MAF and turbo (one without a fitting for recirculation), replaced it, car ran better. It idled better too, just not clean enough. Slightly adjusted the throttle wire/cable on the TB, the car ran fine it seemed. Measured the emissions yet again, and they were fine - AFR was also at around 14 all the time.
So I was confident, booked a new time for inspection. The inspection was today - yesterday the uneven idle came back, my AFR once again reads 12-13. So failed the test again.
Another thing to point out - the O2 sensor/voltages. The car is mapped and uses the O2, and if I check it's voltage with the PFC, it shows a reading between 0.84 and 0.88, it goes up and down randomly. I thought it was supposed to jump up and down, like between 0.1 and 0.8/0.9? Isn't the higher voltage = more fuel/richer?
Or maybe there's something with the IACV?
I don't know :( So im really begging for help!
Relevant parts list to my problem:
- 1995 blacktop SR20DET, forged bottom end etc
- PowerFC w/ commander (no Datalogit though)
- HKS Stage 1 cams
- 850cc injectors
- 3" exhaust from the turbo, SSQV, 100-cell Catco cat, custom made exhaust manifold
- Walbro 255lph pump, EGR removed, Z32 MAF, FueLab 1:1 FPR
Car was built, dyno'd/mapped to just about 400 flywheel hp.
Installed the Catco cat before inspection, measured my emissions and they were good/passed. Then went on to recirculate the BOV.
Went and did the inspection, failed the emissions test. After that, noticed that my manifold was cracked, thought that was the problem, so gave the car to a shop for a custom manifold. Got the car back, measured again, still very bad emissions.
Now, I don't have a wideband O2, all I have is the Apex'i turbo timer that reads the stock O2 and calculates the AFR - now I know this is not precise at all, but so far it has given me an idea of what the AFR is, so it works for me at the moment. The idle AFR I had when i failed was between 12.6-13. So very rich.
So, then after some research I found the problem - the recirculation of the SSQV. Removed the recirc hose, plugged the recirc hole in the pipe between the MAF and the turbo with my hand, a friend checked the turbo timer - 14.1 steadily. Great, put the hose back on, drove home, came to the parking lot and my idle began to bounce/jump up and down, like a vacuum leak.
Video of the idling (it's not as bad right now, but still..)
sr20det idle Pictures, sr20det idle Images, sr20det idle Photos, sr20det idle Videos - Video - TinyPic - Free Image Hosting, Photo Sharing & Video Hosting (http://tinypic.com/player.php?v=2rcrj1x&s=7)
Didn't have time to do anything about it then, had to take first things first - went and got myself a replacement pipe for the one between the MAF and turbo (one without a fitting for recirculation), replaced it, car ran better. It idled better too, just not clean enough. Slightly adjusted the throttle wire/cable on the TB, the car ran fine it seemed. Measured the emissions yet again, and they were fine - AFR was also at around 14 all the time.
So I was confident, booked a new time for inspection. The inspection was today - yesterday the uneven idle came back, my AFR once again reads 12-13. So failed the test again.
Another thing to point out - the O2 sensor/voltages. The car is mapped and uses the O2, and if I check it's voltage with the PFC, it shows a reading between 0.84 and 0.88, it goes up and down randomly. I thought it was supposed to jump up and down, like between 0.1 and 0.8/0.9? Isn't the higher voltage = more fuel/richer?
Or maybe there's something with the IACV?
I don't know :( So im really begging for help!