Hey guys I am having a slight problem with my AFR's when I am driving at a constant speed in any gear. It seems that it spikes lean and then back to normal constantly until I give it more gas. Afr at idle are good just seems to spike lean then back to normal and continues this way until I add more gas then it is good

I have checked and adjusted the tps and it's in spec but could it still be faulty?
I made the fpr vac line go to front of manifold

Appreciate any input. Im suspecting the fpr is bad

 

What AFR numbers are you getting? When you say "adding more gas"....are you tuning the car?

 

Sorry by adding more gas I mean pressing the pedal down more. AFR's are good at quicker acceleration but at a constant rpm it jumps from about 13.5-16 constantly back and forth, you can feel this surge within the car

 

I am on the Pfc base map with some changes right now but it was doing this as well when I had the pettit ecu installed as well

 

More info:

Turbo single or twins?
Fuel pump, stock?
FPR, Stock?

 

Twins on non seq
Supra fuel pump
Stock fpr

 

Needs a tune. Always find it funny why people think the car will run perfect converted to non-sequential with all the emissions deleted on stock ECU. It'll run but you'll have problems like your experiencing. So you can either live with it or get it tuned.

thewird

 

It's on power fc right now and before non seq it was on pettit ecu and did the same thing

 

Base map powerfc is still a stock tune. Pettit ECU only changes under boost, its otherwise a stock tune.

thewird

 

As well as all emissions was hooked up as well when this was happening

 

Convert it back to stock, your problem will go away.

thewird

 

Car was almost stock minus cat back when problem was occurring as well, any rpm at constant throttle is only time it happens. Will be getting it tuned hopefully by you Marco but was trying to fix this issue before

 

I've seen your exact problem more then once. Tuning fixes it every time. That is why I'm being so direct :P

Other then that, try a quality injector cleaner like Royal Purple? These injectors do clog up after all these years and I've seen 20% changes in fuel demands after cleaning stock injectors (actual cleaning, not injector cleaner).

thewird

 

Okay perfect I just found it weird at any rpm at constant throttle. Thanks for the help! Now time to book me in for a tune once I get injectors!