My father'* Oldsmobile is acting up again. Pretty much the same symptons as in this past February:
http://www.bonnevilleclub.com/forum/...741&highlight=

We changed the PCM back then and it worked fine until now (actually it worked until he has to drive thru a foot of water). Houston is known for flooding because we are too flat down here, the rain water can't run off fast enough. The check engine light came on shortly after he drove thru the water, and afterwards:

1. Check engine light will come on randomly while driving.
2. Car stalls occacionally while cruising (three chimes and three lights on the left IP).
3. Car sputters at take off (not sure if this starts happening before/after the flood water. I will ask dad).

So at first, I thought it'* the PCM, went back to the store and got a replacement unit and swapped the PCM. But problem still exisits. Went to Oreilly'* auto parts, and they have AutoXray 2000 that can read the hybrid PCM, and got the code out to be - P1406 EGR pintle position. Cleaned the EGR valve with GUMOUT, not much carbon deposit there in the first place. Check Engine light still comes on randomly (according to FSM, if EGR signal is out of range twice in 20 seconds, it will cause the check engine light to come on).

Any idea? BTW, plugs and wires were changed about a year ago, car is at 153,000 miles. Thanks in advance for all the inputs.

Is inside the car, floorboards getting wet when these issues show up?

To the touch, the carpet is completely dry, and no water enters the vehicle anywhere to my knowledge. Car did not stall in the flood water. It'* been two/three weeks since the high water incident. I will open up the carpet and check the ground terminal on both driver/passenger side this afternoon.

Good plan, my thoughts were something under the hood, or inside is getting wet and grounding out.

Also check the connector at the base of the ignition control module, that could be a culprit easlily.

Also you could get a false EGR pintle code due to a vacume leak somewhere on the intake. Check all the hoses, and the PCV seals, wouldn't hurt to clean or replace it.

Maybe the EGR is working fine, but the EGR position sensor is out of range. Or... maybe the EGR is stuck in the open position causing the engine to drown in exaust. In the old days you could cycle the EGR by applying vacuum to it, but now they are operated with an electric solenoid.

I've never heard of an EGR causing a stall. I'd set that idea aside for the time being.

Random stalling is typically loose or corroded battery cables. No kidding. 90% of the stalling issues come back to that. Clean both ends of each battery cable including inside the boots of the battery ends. Reassemble with dielectric grease.

In the meantime, watch the oil pressure carefully. Does the pressure drop just before the stall, or after the stall? If it drops before the stall, the PCM will cut off fuel to save the engine.

Thanks for the suggestion. Went to clean the cable at both end, and while at it, took the car to auto parts store to have alternator/battery checked. Turns out battery is dying so we replaced the battery. Right away, the problem of car sputtering at take off is gone. So far no Check Engine light or anything else, but it was only a short drive home from store. How can you tell that battery is going bad? I thought cranking put the worst load on battery, but this car has no problem starting up.

I will update the thread when there'* something new.

I hope this catches Bandits eye...

Look at ELECTRICAL before fuel or controls on stalling or fail to start. ALWAYS.