i just put in a a rebuild motor and a single turbo. i fired it up three days ago and it started fine, then yesterday after giving it gas while idling, raising the rpm to about 4500 the car started to get really rich and poping. thinking that maybe the pfc might be acting up i switched it to the stock computer and still back firing and very rich. so i switch it back to the pfc in an attemp to lean it out a bit and still no change. so i desided to take the motor back out and check to see if if was losing compression and took the manifold off to check the condition of the apex seals just incase it detonated, but when i look inside everything looks good so the only thing i can thinck of is either the timing is off(which i doubt) or its dumping fuel. i guess my question is do the secondaries spray at idle (by the way they are 1600's with resistors) which could cause a rich situation? Is there a program in the computer that will change the setting if the car continues to be lean? If the secondaries do fire during idle could i have installed the resistors on the wrong wire? if so which wire is the correct wire to install the resistor to (if looking at the secondaries with the male portion of the harness facing me is the left lead positive orr neg.)? i know the thicker wire is the positive but i m cofused with the leads on the injector or if it makes a differenc at all.

 

hmm... sounds scary.
The secondaries only come on after I think 3-4k can't remember where but not at idle... that was alot of work for some backfiring... is the exhaust spitting anything out?
-R

 

Being single turbo, I imagine your airpump is not hooked up. Make sure your O2 idle control function or what ever it is called, is turned off on the functions menu.

Many PFC users have gone into their boost control map menu, and not knowing it; turned on one of the optional maps. These do not work unless you have the special boost control kit. If no kit, then the engine goes into limp home mode.

 

secondaries come on after your primaries go over 70% duty cycle, please read wade's site on more info on this (its called injector staging)

BTW: yeah thats a hell of a lot of work for back firing. what you might wanna try to check is if one of the injectors are leaking. good luck

P.S. how much are you leaning it out at idle?