OK. This is a beaut.

A few days ago I had the '98SSEi in fairly extreme thermal conditions. I went to pick up my wife at the airport. It was about 95*.

Since I was on the Blue Route to the Phila Airport, I had to do (I'm not kidding) 85-95mph most of the way to keep up with traffic. When I hit the Airport, we ratchet down to stop and go. Then when I am about to accelerate, she rumbles a bit and cuts out.

The temp had been up there, but only 210* or so.

To keep this short (for me), I read a DTC P0530 while I'm sitting there with everybody honking. A/C REFRIGERANT PRESSURE SENSOR CIRCUIT. and something to do with the fans clutching. I'm game so I get out and check. Easy fix, as the sensor had gone disconnected.

This had been about 10-15 minutes. I connected it, jumped in the car, and it kicked right over.

So I'm tooling around looking for my wife'* gate, and wondering WTH THAT SENSOR COULD POSSIBLY HAVE TO DO WITH THE CAR CUTTING OUT.

I found out, and mentioned the DTC just in case,..... it had nothing to do with it because the car suddenly cut out again. I had the car airlifted back home.

The next day, I'm going to try to figure it out.

I just startup the car and left it running. Everything is reading beautifully on the scantool. Air/MAF/MAP pressures, and the fuel trims are almost pegged at 0.0. So I got out the lawnmower and left the car running.

About a total of 25 minutes go by and the car goes apespit and cuts out. There is a distinct aroma of fuel and some exhaust smoke.

I wait 10 minutes, and I'm going to catch it this time. She kicks over and everything is reading perfect/pristine again.

Suddenly the fuel trims start heading South and fast, within a minute they are both -19.4 and the car craps out.

Finally, here'* my problem, not one DTC has been thrown. And now the car starts for about 5 seconds and floods out. I can't tell if the air levels are calling the dastardly fuel, or the fuel is just taking a dump because it feels like it.

What'* my best bet to unwind this sucker? My best odds say I fried something at the Airport shootout.

Without anything to read-out, where should I start? I have my eye on the FPR, but I don't know how to to test them because it could be a sensing problem or a screwed diaphragm.

Any suggestions are welcome.

Thanks.

I would start with a fuel preasure gauge and see if the fuel pump is getting hot and crapping out. To test the FPR you need to use a vaccum pump with a gauge on it and just see if the diaphragm holds vaccume and doesn't fill the vacuum line with fuel.

if the fuel checks out, it sounds like the common crank pos sensor issue. sometimes when it gets bad you can see the tach reading look weird before it cuts out.

I agree, check fuel pressure and fuel pressure regulator. The computer is pulling fuel because it is running rich. Ignition control modules have also been known to fail in this manner, which will also explain the behavior. If a crank sensor is to blame you should be able to see it with the scan tool because the engine speed will be irradic.

I'm not so sure you can detect a bad crank sensor with a scanner, but if the CPS is your problem it shuts the enginer down like you flipped a switch. Your description doesn't sound like that, but you have to be the judge. Personally, I think its the fuel pump, but it certainy doesn't hurt to check the FPR. Just pull the vacuum hose off the FPR and smell it for gasoline ... if you smell gasoline change the FPR.

Thanks for the suggestions. Much appreciated. I'm at work now, and won't be able to get after it till later. I do have a question though.

At one time or another, I've had to replace the sensors on that circuit that runs under the accessory side from the ICM.

IIRC, when the crank position sensor gets wonky, it just annoying cuts out. There is no extreme flooded condition like I'm getting.

Am I remembering correctly?

With the fuel trims spiking like you mention, it really does not sound like a CPS problem, as already mentioned, check your fuel pressure before the problem, and right after the problem happens, also check the fuel pressure regulator, here is a video of a way to test it if you do not have a way to pull a vacuum on it.
The part you want to see is around the 1:50 mark.

Thanks for the reference. I ran into it in my travels last night.

But it demonstrates my quandary. I have fussed around with it to the point where she just kicks over for a few seconds, floods, and dies. Beyond a KEY ON check of pressure, I don't have anything which I can read or check at idle. Even the KEY ON is a static state, and the stuff hits the fan only when the motor is fully over. I can start benchtesting sensors, but that is far from foolproof.

It'* more of a "probabilities" troubleshoot and I need more experienced heads in Bonnevillism than just mine.

I'm going out now to work on it. Over the years I have accumulated a storage box (and garage) full of parts. Maybe I have an FPR in there.

Thanks again.

if you check the pressure key on engine off, alot of times the pressure will bleed down if the fpr is bad. (supposed to stay there for a while)

Hmmm. There is some bleedback during the first 15-20 minutes. I'm not sure that hasn't been there for a while. When I replaced the fuel pump a few years ago, the noise suppressor thingee attached to the sending unit was not snug at all. But I didn't replace it. I think I saw some bleed then, but my advance and trims have always be so tight, I never went back to it.

So, it could actually have been the FPR? I replaced the FPR when I got the car 6 (whatever) years ago. But not since then.

There are a few things I can guess at, and do rather cheaply, which will cover a lot of territory.

I'm gonna start with that FPR.

Thanks. And keep any thoughts coming.