Idle issues continue

[chrissbee77]

HAve a01 grand prix 3.8 gt non- supercharged. Here is the long rundown.

Bad CAT (replaced at meineke) $600
Check engine light code P0420 (replaced the oxygen sensor today)

The P0420 code would not shut off i cleared it and it came back. SO finally changed it today. WAs leaning over the motor and while changing it i smelt fuel. Realized that i was pressing down on the connector that goed to the fuel rail. i changed the connector but it still leaks a little when i push on it or move it. is this normal?

ARE YOU READY FOR THIS????

O2 changed light gone. (great) Know every damn code you can think of is comming up

P1108 MAP/BARO range
P0102 MASS/VANE
PO441 or something that has to do with the purge vent solenoid EVAP canister (fault C).

So i went crazy and took the fuel rail connector deal thing after i got sprayed with fuel i put it back on and thougt that maybe i flooded the canister or something/

Car wouldnt start up so i changed these sensors, (mass,iacv,map,air temp,egr valve, tps, cleaned the throttle body, checked for vacum leaks(found none) car starts but the idle goes from 1400 rpm to 800 and fluctuates within this range) Put it in drive and boom goes the check engine light and i get all of the same damn codes (mass air flow low input, evap purge deal thing,) WHat did i do and how can i fix this,.

Ps IF you start the car and leave it in park while giving it gas once the engine RPMS hit 4200-4300 the exhaust pops and wont go past that.


IM SORRY FOR THE CONFUSING POST BUT I WANTED TO BE THOUROUGH

[chrissbee77]

HAve a01 grand prix 3.8 gt non- supercharged.
broke down and took car to the dealer after i posted the codes i just gave up. They replaced EVERYTHING again and it still bounces at idle. They said they tested the MASS air flow sensor and it showed 0 reading. they told me i needed to replace the ECM. They dont no why the EVAP PURGE vent canister code will not clear. They Want 849.62 to replace the ECM and to flash it as well. they also said that the bad ECM is the reason the cars exhaust pops at 4200 rpms.

Am i getting screwed? how can i check the ECM, fix the idle, and what is a pruge canister and why cant they fix it? thanks guys.

[BNaylor]

The evaporative emissions purge cannister aka charcoal cannister is easy to replace as is the vent solenoid so there should be no issues on that.

You can get a PCM module a lot cheaper than what the dealer wants but to determine if it is bad or an output driver issue you need a GM Tech II scan tool or just replace it to rule it out or in.

BTW - I merged your two posts on the issue(s) to help cut down on redundancy or confusion.

[tblake]

Take a picture of where the fuel is spraying out. If you took it apart, did you replace the o-ring?

[RahX]

Your car has a park/neutral rev limiter which will not let the engine rev past the range you described, that is completely normal. I would take it somewhere that actually diagnoses problems instead of replacing parts for no good reason. Without looking at it, I would say it is some sort of electrical problem. Did you damage anything else when you were changing the O2 sensor? Fuel leaking is not good, you should probably take care of that asap.

[BNaylor]

With the exception of any EGR DTC(s) what is common to all sensors or components listed is the IGN1-UH fuse at the main engine compartment fuse box. Check to see if it is blown or look for 12 volts at ignition to ON at one side of that fuse socket.

[chrissbee77]

I went to the pontiac gm dealer its a new MASS sensor .. I will check the fuse asap and post the findings. thanks for the help.

[chrissbee77]

I have a 01 gradn prix 3.8 n/s gt. what is IGN1-UH fuse used for. what happens when it blows

[richtazz]

I merged your two threads as these are obviously the same issue.

As BNaylor (Bob) stated in post 6 in this thread, all the components for the odd codes you have popping up are controlled through that fuse. So in essence, your symptoms are what happens (or can happen) when that fuse blows.

[chrissbee77]

the fuse was blow i put another one in and cleared the codes so i will drive it and let you guys know. I cant thank everyone on this forum for all the help with this issue and the host of other things that i have been able to change with your advice. just wanted to say thanks.