CyCloNe!

Hey guys I'm having some idle issues that are giving me a headache... I've been running a 90mm lightning maf and stock injectors without issues. I just recently got a retune and am now running 80lb injectors with the same 90mm maf. Before the install the car ran great no issues, now my new chips the car runs excellent when warm but if its real cold on start up for about a min the car is having an extreme hunting idle it will go from 1k RPM to 2K RPM repeatedly back and forth instantly.

I've tried to Adjust my Idle and for what ever reason it won't set it just keeps going back to what it was. I've checked my TPS and wiring, all was fine but I decided to replace the TPS just in case. The ISV is new as well, all vac lines on the car are new and have been checked.

Any ideas will be greatly appreciated.

CyCloNe!

Just trying to narrow things out.

blown 944

Do you have a wideband hooked up? If not that is not a good idea considering this is custom tuning. If so what are the afrs? And maf voltage?

There have been a few changes since the first design and one is in the idle code. Honestly, it's best to try to contact the vendor first to get this dealt with.

CyCloNe!

Vender has been contacted, so far suggestions were the idle adjustment and the tps sensor/wiring. I have sent another message a day or two ago, just waiting on a reply.

No wideband at the moment, I have a narrow band that I can install to get an idea. Still running factory k26/6 at the moment, was waiting on wideband till I got the turbo I want in hand.

lart951

faulty injector

CyCloNe!

didn't think of that... would it do that just on cold idle though? On my smell-o-meter I don't sense any extra fuel coming out, I'll hook up the narrowband and hopefully that will give me a little insight.

blown 944

Have you tried changing the fqs setting?

Tom M'Guinn

Are you running 80 lbs injectors with a stock DME (i.e., just chips, no chip board with rewritten code)?

CyCloNe!

I have not but this was presented from the vendor as well so I will give that a shot. Isn't the FQS setting on the back of the dme?

zerMATT951

Disconnect your ISV servo and see of the hunting stops. If it does the problem is likely your TPS.

I understand that you are trying to keep the chip vendor name out of this, but you need to realize that leaving out that key piece of information will result in chasing ghosts and will waste your time...

Bri Bro

Look here:
http://www.lindseyracing.com/LR/Parts/DMEFQSSWITCH.html

A golf tee and a Q-tip (remove the cotton) work better since they don't score the plastic inside the FQS swith.

CyCloNe!

Hey guys I may have gotten the problem fixed. So far the car is running fine on a cold start up the past few times I've tried it. So it looks like a misaligned TPS sensor and an idle adjustment may be the issue. It was brought to my attention that my idle range was higher than what the chips were programed for and was causing my sensor to fight against the programming. I had tried adjusting the idle before with now luck but since my TPS was turned higher on the throttle body it made so the adjustment was working correctly.