2002 SSEI RPM's Drop to almost stall condition

[bmac]

If I've duplicated this issue I apologize, I searched the forums and didn't find this specific problem.

I recently purchased this car and before I did, it stalled on me a couple of times and had a long crank time one time after stall during test drive. With my past experiences on my NA 3800's I quickly thought that it might be a Crank Position Sensor or Fuel Regulator. They told me this had never happened and they would get it fixed. Long story short several different mechanics they took it to replaced numerous sensors and couldn't resolve the problem. They told me they were tired of throwing money at it and gave me a pretty decent discount to purchase as is. (Couldn't pass on the opportunity to own my first SSEI)

So I haven't done anything to it yet, but I've been able to isolate the problem. Seems that after the car has run and warmed up to normal operating temperature that when setting still (idling) and with the car in gear if I turn the steering and put additional load on the engine it stumbles and the rpm's drop like it's going to stall. I can do the same thing with it cold after start up and it keeps purring along. No sensor on the Power Steering pump on this year. Something (assuming a sensor) doesn't seem to be communicating with the PCM after it gets warmed up when the additional load of the power steering is applied while idling.

No Service Engine Light, Supposedly all the sensors have been replaced or checked and the TB was cleaned. I haven't not had to verify any of this as I've been trying to get the 2000 SE back to form after replacing the engine. Another issue with that.

Any thoughts or ideas on what to check would be appreciated or if someone else has had the same experience let me know.

[AJT2004]

Do you know specifically which sensors were replaced? Also, it is not uncommon to have a non-OEM sensor to be at fault. Trying disconnecting the MAF sensor and see if that helps. It's a good place to start and cost zero. Next thing to check is routine maintenance items- plugs, wires, air filter etc.

[Archon]

Do you know if the idle air control and passages were cleaned when they cleaned the throttle body? If not, you may want to do that. If the IAC is slow to respond, due to being dirty, and sticky, it could cause that symptom. The higher RPMs while cold would make it less of an issue.

[bmac]

They supposedly changed the IAC, because that's what everyone thought would be the issue. I have not verified any of the sensors and I pretty much guarantee you that they probably didn't replace all the sensors with new ones just from looking at them and I'm pretty sure I seen the tell tale paint pen marks on some them (EGR Valve) that you get when you purchase a part form pick-n-pull or u-wrench it.

I appreciate the suggestions I when we get done with the P0401 issue on the 2000 SE and some decently warm weather I will dig a little deeper into the TB cleaning and IAC.

[jradke61]

I'd be looking at fuel pressure.
And vacuum?

[maxi426]

All good suggestions. I'd double check that the bore of the throttle body has been cleaned well right at the point where the throttle plate sits at idle. Can you swap the MAF sensor from your other car?

[bmac]

Well, I've changed the MAF sensor from my 2000 NA bonny with the 2002 SSEI bonny and I've noticed that my 2000 NA is acting somewhat the same as the SSEI was with the same MAF sensor. However the SSEI is still doing the same thing as before, I just don't know if it's as bad. One think I've noticed is that my 2000 NA idles at around 800 RPM and I think that the SSEI is lower than that, around 600.

The power steering still seems to me that after it warms up it's stiffer than when at idle cold. It definitely is stiffer/harder to turn than my 2000 NA when driving down the road.

I still need to verify and check all the things mentioned above. However that might have to wait until spring arrives. Not the best conditions to work on a car right now here with the temps in the teens.

I have my old NA running good now and it turned out that my new MAP sensor was bad.

[maxi426]

Your SSEi should have speed sensative steering. The SE likely does not. SSEi will be stiffer going down the road

[MKMike]

Well, I've changed the MAF sensor from my 2000 NA bonny with the 2002 SSEI bonny and I've noticed that my 2000 NA is acting somewhat the same as the SSEI was with the same MAF sensor. However the SSEI is still doing the same thing as before, I just don't know if it's as bad. One think I've noticed is that my 2000 NA idles at around 800 RPM and I think that the SSEI is lower than that, around 600.
I have my old NA running good now and it turned out that my new MAP sensor was bad.

All too common are brand new defective parts. At least the MAF is a quick job.
Hitachi made the OE Maf sensors and Amazon and Rockauto sell them.
Rockauto gives forum members a discount with the code found in their Vendors Forum on Pontiac Bonneville Club