misfire at idle.

Actually, it is open loop at startup and closed after warmup, but otherwise correct. As for PE thing, I don't know what your enables are set for, but light throttle should not put you in PE, over 50% certainly will.

well either way im going to replace the o2 now. haha

worst that'll happen is you'll be out $100 and you'll get better gas mileage.

yep.

well, i just got the fuel pump, so now all im waiting for is the front o2 which will be here sometime tomorrow from ZZP.

could have jusy gone to napa or similar for that

Yep sometimes paying the extra dollar or two is worth it.

well napa wants $120 for the front o2. i got it for $55 shipped, sorry not paying close to $70 extra just to save on one day of shipping.

Ya I thought you can get from ZZP for arond $50, screw $100+.
Think my sensor may need replacing.
R.S.- I thought -16.4 was max too, but i've seen mine in the -22 range before!!

-22.6 is the max the motor can pull. +16.4 is the most the motor can add.

well i got the o2 sensor. Just waiting for you to stop up here sunday. Boosten should be here also, unless he decides to head back to chicago sometime sunday.

Just get under the car and do it. You don't need extra hands for those jobs.

i am waiting for him so he can do a maf tune, because zzp tuned the car with a bad o2

No, they should tuned your car with their own wideband o2.

Your car is not running properly because it's not getting enough fuel.

The computer uses your o2 values to determine whether to add or remove fuel. For some reason, your computer is adding all the fuel it can, based on lean o2 readings, and it still isn't enough.

That is why you are replacing your fuel pump. The computer is seeing a lean condition because your fuel system isn't flowing enough fuel to the injectors. This is causing your system to run lean, which is observed by your o2 sensor. Your computer is compensating for this by flowing as much fuel out the injectors as it can. However, it isn't enough.

That is all assuming that your tuning isn't just really freaking screwed up, but I've checked on that. And what I've seen is that a lot of your tables seem to be adding more fuel than normal. More fuel because your fueling system isn't working properly. Hence, the importance of the fuel pressure test.


For example, in a perfect system, your fuel pressure is 60psi. Your injector pulse width is 2.1ms at idle based on the o2 readings as well as tuning tables like IFR, MAF, etc.

However, let's throw a wrench at that system. Your fuel pump isn't working the greatest and it can only provide 48psi of fuel. The tuning still says that your injector pulse width should be 2.1ms at idle, but because of the pump, those same 2.1 milliseconds aren't flowing enough fuel. The o2 sensor reads that as a lean condition. It will adjust the fuel cells to add more fuel. Now your injectors need to be open 2.8ms to flow enough fuel.

That is what is wrong with your car Tim. Only in your case, it's so bad your computer can't flow enough fuel to fix it.


I'm positive that once we put that pump in, I'm going to scan your car and she's going to be PULLING fuel because your tables are set so rich due to a failing pump. Probably enough fuel that I'm going to have to drop your MAF table to stock and scale your IFR down for your L67 injectors just to have a baseline for how bad it was in the first place.


To be perfectly honest, your o2 sensor is probably fine. But don't worry, if it is I'll buy the new one off you because I *do* need a new one.