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I am having issues with the car ONLY when driving passively typically bellow 3k rpm's. The car runs incredibly well at WOT. The data logs are very good at WOT.
When driving around town or on the highway below 3k rpm, the car is constantly making corrections causing an "up and down" sensation & lots of hesitation. The car cuts out every time after reapplying throttle after coasting in gear. The gets utterly confused when doing low RPM roll ons. I am getting no codes whatsoever. Cold starts are bad as well...starts up fine but goes really bad as soon as the SAI kicks in about 5 seconds after initial start up. About 30-45 seconds after start up, and I believe as soon as the SAI shuts off, it idles perfectly. The data logs show that the car is making constant adjustments for some reason.
I've done countless boost leak lest test...no leaks + I don't think it's a boost leak issue anyways as am making incredible power & boost at full throttle + the data logs at WOT are great.
One of the "ideas" has been that perhaps there is a vacuum leak as my issues are when I am not boosting. Maybe a faulty check valve? Faulty EGR vacuum solenoid? Faulty secondary air injection check valve? (I've ordered all of the above solenoids and check valves and will be replacing those soon.)
I thought I might have a bad ECU so I sent it out to have it checked out and to make sure it was working correctly. They cleared it out and returned to OEM specs.
Unfortunately, I am on the east coast and my tuner is on the west coast. For the record he has been great but is limited with what he can do not to mention that the issue is not with his tune as it has been done many times on other cars.
This has been going on for nearly 3 month and I've about had it...Hoping someone out there experienced this and can help.
for starters, have you tried doing an e-throttle reset/calibration?
also, you say the ECU/DME was reset to OEM spec but note you have done (presumably) larger injectors..
for starters, have you tried doing an e-throttle reset/calibration?
also, you say the ECU/DME was reset to OEM spec but note you have done (presumably) larger injectors..
Yes I did a TB reset. I had the DME reset before I downloaded the new file for the injectors and mods.
I'm referring to a recalibration if the new t/b nor a reset. It requires 1 person to open and close the butterfly per the request of a tuner who is inputting calculations to tell the dme that there is a larger t/b and the opening and closing ratios
I'm referring to a recalibration if the new t/b nor a reset. It requires 1 person to open and close the butterfly per the request of a tuner who is inputting calculations to tell the dme that there is a larger t/b and the opening and closing ratios
Understood, but I had these issues with the stock TB & injectors as well. For some reason the DME feels the need to make constant corrections to the fuel air when the car is being driven casually / easy.
Understood, but I had these issues with the stock TB & injectors as well. For some reason the DME feels the need to make constant corrections to the fuel air when the car is being driven casually / easy.
that was a minor piece of info you didn't tell us. having issues with the car and throwing tons of mods at it before finding out what is wrong just leads to more problems imo
This is a long shot...but...Is the MAF oem? There are A LOT of fake/counterfeit maf's out there. They look totally authentic at first glance but do not work properly.
Pull up the rubber boot covering connections on MAF. You will be testing the pin furthest away from you when standing behind the car. Use the grounding lug of the fuel filter that is near by for ground.
With car off but ignition in position 2 you should get between .9 and 1.1 volts.
Then start the car and get it warmed up and test voltage again. Now you should get 1.2 to 1.5 volts.
that was a minor piece of info you didn't tell us. having issues with the car and throwing tons of mods at it before finding out what is wrong just leads to more problems imo
It's a long story...the car ran fine for 4 years with just a stage 1 chip/tune from a tuner here on the east coast. I never intended to do all these mods. I was only going to do billets and intercoolers to slightly improve what I already had. Then the coolant hose issue reared it's ugly head and the engine was going to be taken out to do the coolant pinning mod so I decided to go all the way. I went with a different tuner for reasons I'll keep to myself as I do not wish to start any debates or conflicts.
10-12-2015, 06:44 PM
