Ok. i have a problem and i need help. I have an 06 ix mr with a few bolt ons. nothing major. intake walbro 255 and ams fpr. and my issue with my car is that around 3500 rpm right before spool. It starts to sputter and lag horrible. but my check engine light just says buring to rich. Bank 1 sensor 1 and buring to rich(pending) what are some fixes? im at a lose.

 

I have the same car, our cars run rich naturally, as for the sputter, I believe there's a how to thread on taping the lower intercooler piping, also u should check for a boost leak, there's another thread on how to make ur own boost leak tester, hope this helps. One more thing, before my car started to throw the same code as hrs, my front oxygen sensor went bad.

 

Does it boost cleanly past 3500rpm?

Check plugs. Check charge piping for leaks with a boost leak tester. Check AFR's (you do have a wideband, right?).

 

Check your plugs.

 

You mentioned you have a AFPR and Walbro, what's your base fuel pressure set to? If it's too high you could be getting way too much fuel at spool up. Have you been tuned since you installed those parts? I would bet a good tune will solve your issues quick.

 

I hacve not got it tuned. yet planning on it. But with the plugs what could be the issue there?

 

It boosts fine if i put my foot into it. its just when i accelerate normal does it lag and sputter.

 

well duh, if you have not tuned your car then i can see you having problems

 

If you've made changes to the fuel system then I would almost guarantee it needs a tune. My guess is that your fuel trims are way out of line.

 

In this order:

Check fuel pressure setting

Plug gap

Boost leak test

 

Not true. You don't have to tune to stop the "sputter". He is still running a MAF. A tune would be recommended to get the best out of his setup and the bang for his buck. IF he had injectors than this would be true.

 

Ed?