I'm trying to sell my current FC that I have so that I can move back to California to continue school. The guy's that came out today and test drove it brought something to my attention that I never knew. When your going down the road giving it about 30% throttle its fine. When you give it 100% throttle it bucks a little and then it doesn't want to go. Sometimes it would die and other times it wouldn't. The only things I've replaced on the car is. OMP, ecu, rear calipers, fuel filter, whole entire fuel pump assembly ( this came out of an S4). I think it could be a fuel issue like its not getting enough gas when I try to give it 100% throttle or maybe a air issue? Can somebody help me out here please! I need to sell my car to continue my education!

EDIT: Its a 91 NA and this happens when the car is arounf 4k rpms. Possibly the secondary injectors? I don't know pretty new the the rotary would and everything seems to be a pain in the *** with them. Possibly a vaccum leak somewhere on the car?

 

I think its the whole 3800 hesitation ****. I'm on arron cakes site checking the grounding issue thing. Tomorrow morning I will go out and check this out. I hope this is the problem so possibly a quick fix even though that ground is under the ******* intake manifold -_-

 

3800 rpm hesitation typically happens at low throttle. And it's just going to be a stumble while the secondary injectors transition on. It's not going to make the motor completely stall.

Can you make it stall if you give it full throttle under or above 4k rpms? Or is it only at the injector transition point?

If the TPS is not working properly, the ECU might not provide enough fuel at WOT. I'd test the resistance values and replace it if it fails. Test info: http://howto.globalvicinity.com/gv_w...i=58&co=1&vi=1

 

The s4 fuel pump assembly is a inch or so shorter than the s5. Don't know if that's your problem or not. How much fuel is in tank, may not be getting to it.

 

s4 have grounding problems alot, i would check that out first thing.

Then again your problem could be the alternator with a blown diode feeding a/c voltage into the dc lines and causing it to be thrown off and confussed.

 

Oh I forgot to mention the TPS was replaced also. I know it needs to be adjusted too because it idles at 2k when it does that cold start warm up jumps to 3k so that may be the problem! Also I'm going to clean all the grounds up too. I wish it wasn't so cold out side either.


Edit: Also yesterday when I drove the car at night I pulled the battery out of the car and it seemed like the alternator was going bad I was driving then all of the sudden the car lost all of its power and then I coasted home. Turned out the main 100A fuse in the fuse box under the hood had blown.