wierd things with PCM

[Watazz]

Alright so I noticed I had an exhaust leak the other day right where the pacesetters meet the Ypipe and I tightened the bolts up and no more leak so no more problems. However this made my wideband read differently. I went from being a solid 11.5-11.9 AFR to 11.5-12.5. So I went to my command as I was commanding 11.9 and changed it back to 11.5.
This made my AFR go back to the 10's. So I figured I would just change the command back to 11.9 and do the rest in the PE table.
well I changed the command back to 11.9 and it is still in the 10's. And I changed literally NOTHING else. So WTF?!?
Does the PCM have to reset or somethin? I just dont understand.

[ssms5411]

Re: wierd things with PCM

The PCM will reset , but if your running that rich I would check your spark plugs , I know mine were so junked up from running rich , my A/F would read 12's at idle after I changed them out right back to 14.7 at idle. Running rich will throw off your A/F's , so I would pull a plug and check it mine had junk all over them, from running rich too much. Good luck with it.

[Watazz]

Re: wierd things with PCM

that makes sense. Ill give them a check.

[bigbrian442]

Re: wierd things with PCM

The PE table only changes the fueling when the MAF fails. You need to tune the MAF.

[Watazz]

Re: wierd things with PCM

I thought they only really maxed out on 6lbs with the 99-02 models. Is there a right up on how to tune it?

[ssms5411]

Re: wierd things with PCM

The PE table only changes the fueling when the MAF fails. You need to tune the MAF.

My PE worked N/A and with boost to tune it.

[Watazz]

Re: wierd things with PCM

My PE worked N/A and with boost to tune it.

thats what I thought. I though PE was enabled as soon as the pedal went to the floor on our cars.

[ssms5411]

Re: wierd things with PCM

thats what I thought. I though PE was enabled as soon as the pedal went to the floor on our cars.

It is.

[bigbrian442]

Re: wierd things with PCM

Sorry that's the VE i was thinking of. Your PE still relies on the MAF tune to get close to the commanded AFR.

[ssms5411]

Re: wierd things with PCM

I knew you knew more than that on tuning, BigBrian

[Watazz]

Re: wierd things with PCM

well I leaned the PE out pretty drastically today and the AFR is looking OK. So its all good now just strange as to why I changed it and then changed it back 5mins later and the AFR was COMPLETELY different.

[bigbrian442]

Re: wierd things with PCM

Yea I'm at work and feeling kinda burnt.

[ssms5411]

Re: wierd things with PCM

Yea I'm at work and feeling kinda burnt.

Sorry to hear. Try one of those 5 hour energy drinks.LOL

[Watazz]

Re: wierd things with PCM

Yea I'm at work and feeling kinda burnt.

I know the feeling haha