Still having problems trying to figure out what is making my AFR's bounce all over....symptoms are:
at idle-bounces between hi 13's to mid 15's, in .1 increments but FAST (never did this bfore)
at cruise-hi13's to low 14 (14.3-.4) also .1 increments but little slower (used to be steady 14.5-.6)
at WOT-(3rd gear) steady 11.4-.5 as always

There is a noticeable difference at idle, actsalmost as if starting to lean out, then the pcm calls for more gas and goes rich,
thenit repeats over and over with no change after driving for awhile.

Looking for any advice what it may be--I have a Walbro 255 in for over2 months,installed the PTP FPR mod at same time as the
pump; in for almost a week,but it never worked right so I got a new FPR and car ran fine after that. This has been happening for
a couple weeksnow and isdriving me nuts. Any help would be great!

 

sounds normal. not sure what the issue is?

 

Well, the issue I guess is my not knowing if this change in the way the car runs is o.k. or not or a sign of something going bad.I wish I had video of howthe afr'sused to read versus theway they do now. It's just not the same, very bouncy. If an injector is failing, would this be a symptom?

 

no it's not. the change is probably just due to the pump. more fuel means that the ecu has to pull more fuel to get proper readings. with more fuel it takes a little longer for it to properly adjust. as long as the readings are fine don't worry about it. recalibrate your wideband just to be sure, but it sounds fine.

 

O.K. makes sense w/ the extra fuel; the gauge does stay in range, but how would I recalibrate it for future reference?Also, would a return line help by bringing unused fuel back to the tank instead of the ecu trying to compensate? Thanks again, PSI

 

a return line does help, but with your mods isn't really a requirement. if you want to turn the boost up more then you should think about getting one.

the uego is a little annoying to calibrate. basically you have to make it think that you installed a new sensor. get under the car and disconnect the sensor wires and remove the sensor from the pipe. turn the car on. you'll get an error reading on the gauge. then turn the car off and plug the sensor back in, leaving it out of the pipe. it will free-air calibrate. once it's done, just plug it back into the pipe and you should be good.