Javi802

Does anybody have any advice as to what i should look in to, as my car is running lean (idle) on cold starts as well as misfiring. Yet it is idling rich (12-12.4) once its been driven and warmed up. And still misfires a little. Vacuum during the cold start is at -20, but as it starts missing goes as low as -16. And then back to -20.

I set the engine at TDC and performed a boost/vacuum leak test using my air compressor and only found a leak in one of my intercooler couplers, which i fixed

My o2 sensor voltage stays pegged at either high voltage (.86) or low voltage (0) when this happens too.

Cruising around my afrs are fine and my o2 oscillates as it should. I am running lean under wot though. at 10psi and wot im getting roughly 12.7 a/f.

Car has an enthalpy tune and has been having idle issues from the beginning, but at first my afrs under boost were fine. Was getting about 11.6 on my gauge.

Martin is coming to the area next week and said he would find and fix the problem, even if it isnt tune related(which i dont think it is.) But i would much rather fix it myself and just him fine tune it.

Javi802

Guess i could have added that i did have my injectors tested and at 2ms (which is about equal to idle) pulse width there was a 20% difference between the four.

-2ms
112cc /min
100cc / min
92cc / min
93cc / min

-8ms
686cc
676cc
656cc
667cc

-Static
951cc
950cc
941cc
942cc

Not sure if that info is useful or not

zombiewolf513

Coolant temp sensor maybe

tothyuo

well,Coolant temp sensor maybe

KAT-PWR

This is where I would start

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MRP Manufacturing

Javi802

Would a bad cts cause lean cold start issues? And im not throwing any codes, but I guess it isn't unheard of to not throw codes and still have a component issue.

Im also not having hot start issues. Starts up every time.

KAT-PWR

CTS doesn't seem to like to throw a code and has varying degrees of failure that cause poor running conditions.

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MRP Manufacturing

zombiewolf513

...and its a cheap place to start. Doesnt hurt to have a new one in there anyway even if it doesnt turn out to be the issue

Javi802

CTS is only about 1.5 years old.

And the car only started doing this stuff after adding the t2871r, z32 maf, sard 850cc injectors and the tune.

Ive read that the maf being too close to the turbo can cause issues. Im running a kts (apexi replica?) suction pipe, but im not sure if it is too short.

cotbu

was this every sorted out?

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LoverTechnologies "Half Broken Things!"

Javi802

Yes, kind of lol. Martin at rs enthalpy said something was wrong with how the ecu was interpreting o2 feedback, or something like that. He worked his magic though and got it sorted out. Ill have to see what the car does tomorrow on a cold start though.

rawgarage

Anticipating new update

Javi802

guess I could have mentioned that I did put brand new deatschwerks injectors in it. Doesn't misfire at idle anymore. So maybe it was the injectors?

zombiewolf513

Funny, same thing happened to me last couple of weeks. Misfire at idle... Deatschworks injectors... Better than new. Glad you got this figured out!