Car idles fine once warm. Runs about 13.9 to 15.9 afrs under cruise. The second you step on the gas even a little bit car goes leaner than that around 17:1 to 18:1 ish afraid to go out of vacuum. Dunno whats going on here. Just did the fuel pump re-wire so the walboro is getting 12.5 volts. so i'm really not sure what to check here. Car is running on a Power FC, rich man's non-sequential. Car was running on a PERFECT map before this started happening.

 

Have you tested the voltage while driving? I have a volt meter connected after the relay and I'm seeing around 13.7

Perhaps you didn't do it correctly?

 

Its done right according the the fuel pump re-wire diagram on this forum.

 

Assuming your TPS is adjusted correctly, this may be the typical Power FC tip-in fuel problem. The solution to that is thorough tuning with a Datalogit.

 

Was thoroughly tuned. Drove AMAZING before this suddenly happened. Tony at UMS did a great job with drivabillity tuning as well as power tuning. Car was amazing. Could the TPS shitting itself cause this?

 

This sounds like a fuel Pump pressure issue, I would check and verify your fuel pressure and see under all those conditions of Drivablity.

**Assuming the car was running on a perfect map.

 

yeah it came out of nowhere, i dont have a pressure gauge i'm on a stock FPR

 

works again. little o-ring that seals the pump to the carrier blew out. replaced and fixed works like a charm again

 

I'm having a similar issue! My rx starts up fine and when she's "cold" she'll drive fine but the minute she warms up, she falls flat on her face when I give her gas. For example, Today when I got home from wrk, I started her up and within 2 to 3 minutes of starting her, I backed her out of the driveway with no prob. drove her around the block 2x's with no issue then back into the driveway. NOT BOOSTING!!! (NEWLY REBUILT). I noticed the idle change almost as soon as i got back into the driveway. i also noticed that the vacuum was now at about 16 hg whereas before, it was about 10hg. I have quite a few mods running on the stock ecu. Fuel pressure at 36. Give me your thoughts cause Im wondering if I could have the same issue you did with the o ring!! Not really sure how an O ring would cause my issue; or yours for that matter, but at this point I'll try anything! I'm desperate!!!!!

 

Start taking things apart, check your voltage at the pump

 

well, it wasn't the pump. I actually did the hose and clamps mod when I put in the new pump. guess I forgot! But now I'm wondering if my prob is actually the IAT sensor. After warmup, I believe the ecu reads the sensors to determine A/F. Well if mine becomes heat soaked, or defective enough to NOT cause a CEL, maybe I'm too rich. Just a shot in the dark since I haven't done that mod as of yet. Watcha think?