Help! Need to get to work/school tomorrow

[shafa1121]

I have a 2000 Bonneville SLE with 160,000 that has been throwing P0140 (twice?), weird.

Here's the problem (sorry in advance for the length, trying to get as much info as I remember in this):

A month ago, stranded leaving work. Died, would try to start but wouldn't turn over. Unplugged the MAF and it ran fine, replaced the sensor and things were good, or so I thought.

Last week I got gas, went to turn onto the road and it stalled out on me. Turned over right away, 3 of us messed with it all night trying to get it to die again but no luck. Next morning on the way to work, happened while going about 55, shifted to neutral and restarted. Died a minute later, when I decided it wasn't worth the effort and had it towed to the shop.

Called them at the end of the day and it started right up every time, the only thing he thought was weird was that after sitting for a couple hours and a trip around the block the engine was hotter than it should have been.

It was due for a tune up, so the next day I did plugs and air filter and noticed some white smoke after starting it up again. Had it towed again and it was a busted O ring leaking fuel in the back near the firewall, they said that could have explained the intermittent stalling, etc. Drove fine for a couple days, a little hesitation, but I needed new wires and was waiting to get paid so I assumed that was the reason.

Picked them up and installed yesterday afternoon, started the car and let it run, everything seemed to be running great. However, the code was still there after clearing it so I assumed I'd be getting a new O2 sensor today.

Go to start it this morning to go to work (6 AM, had rained all night) and it was revving really strangely. Not normal and steady, but would go from 1000-1500 to 2500 rpms, and back and forth. Like it wasn't getting power or something. My headlights were dimming while this was happening too. I thought okay, maybe I just need to give it a little gas but that didn't seem to help. Pulled out of my space and the rev continued the cycle. Kept giving it gas and it lurched forward and stalled out. I started it again and pulled into a spot. I feel that the rain last night is a key thing because before it only hesitated a little bit.

My boyfriend had to take me to work today and I missed an entire week of one of my classes last week because I had to wait for him to go home. I NEED to get this fixed asap. I have papers to write tonight, so I'm really hoping you guys can come up with something that I may have missed by the time I get out of work today.

[nos4blood70]

Are you losing any coolant? Also check the throttle position sensor and the MAP sensor.

[shafa1121]

No coolant loss, LIM and all the associated parts were changed out last year. Does it sound like something separate is going on besides the O2 sensor code?

[crash93ssei]

Look for vacuum leaks as well, that could cause the revving, as for the intermittent stalling then no start, that sounds like a bad crankshaft position sensor.

[shafa1121]

It's restarting every time, I just haven't had the time to keep messing with since it keeps happening when I'm on the way to work or something. More like it's restarting and struggling to stay afloat. Someone eles had said TPS which I did have happen on a car with a Series I motor because coolant was leaking, seemed to cause similar symptoms with the shutting off at random but alway restarted and didn't run rough.

[michtom]

I would check the grounds to make sure they are tight and have a load test on both the battery & Alternator done at your local auto parts store. They will do this for free.

[shafa1121]

After much research, I'm leaning toward the IAC and will be checking tomorrow. Still going to check the basic connections and maybe throw the rear O2 sensor on for good measure. After all is said and done I'll drive it down there and have them test it out. Amps seem to be reading normal on the dash monitor though.

[bobgto65]

A bad Crank Position Sensor is a common cause of this issue.

[Q-Ship]

+1 on the CKP sensor. Could also be the ICM on its way out. I've had similar issues with my '01 SSEi and it was the CKP sensor. I've had some other random misfire issues that never set codes but it turned out to be the ICM.

[shafa1121]

Changed out the IAC valve and that helped with the erratic idle. Drove it around last night just fine, no hesitation, etc. This morning I started her up, let it run for a couple minutes before driving. Made it maybe 3-5 min down the road and it started happening again. Was able to restart every time and even drive for a little bit before it stalled again. Seems to only happen in the morning (was about 45 out this morning) so I'm dropping it at the shop after work, seeing as I should be able to drive it in the afternoon. I'll have them check the crank sensor and ICM, but any other theories out there? PCM perhaps? From what I know, that's at least on the same circuit as my O2 sensors and could contribute to the code.

[nos4blood70]

Seems like the problems start when the car warms up, which also points to the CPS.