94 Bonneville Stall Problems while driving

While driving at higher speeds 60-70 mph without warning the engine dies. No bogging out just dies. After pulling over to the side of the road, and placing in park the vehicle will start right back up. Power never goes dead just the engine. Doesnt happen every day just intermittently, so far only while traveling on the interstate above 60mph.

On a side note, and something that I am not always able to duplicate the following occurs- Intermittently the check engine light will come only on startup, but if car is shut off and restarted it will go away, and not return until another time the vehicle is started.


Information gathered of possible causes-

Usually a stall and resart condition is a faulting electrical contact, crank or module

-Check plugs, wires, fuel filter- Appear to all be ok.
-Possible ignition relay problem?
-Check engine ground
-PCM- check for spots on the EPROM
-Possible Problem with Crank Sensor- A known issue that several
people have had to replace. (The crank sensor plug is toward the front of the engine behind the bottom crank pully.)
-Module Plug- The module plug is just below the triple coil pack toward the front of the engine, usually has a small screw on it.

Any help would be much appreciated I am not a mechanic just good
at gathering possible causes of the problem.

Thanks for any help,

Ryan

It would be interesting to see if error codes are stored. This is easy : the OBD1 diagnostic plug will look like this:

www.avigex.ca/xport/plug.jpg

with connectors in slots A,B, and M(under A). If different it is either second series OBD1 or OBD2..that require to be read with a scan tool .

If plug similar, then:
Jump together diagnostic plug connectors A and B with a small wire
TUrn key ON
CEL light will blink code 12 3 times (one pulse of light then 2 pulses, 3 times) then will start giving the codes, if any, like 23 will be 2 pulses, then 3 more..Once finished, it returns to code 12.
codes here:
www.avigex.ca/xport/3800codes.jpg

Come back and pst what you found

Sound's like the Crank posistion Sensor is starting to go.


~Larry~

Thanks guys I appreciate the input very much. LMP great information I am going to be pulling the codes soon, and will post the results. Since sometimes the engine light intermittently comes on I will try to get diagnostics with the engine light on, and off.

THANKS AGAIN!

Ryan

I had a similiar problem with our 94 and I spend almost $1,000 on it and several trips to the dealer. I finally fixed it myself with advice from this forum. Beleave it or not it was the fuel pump relay. Easy, easy fix. Not sure that is your problem but it sure sounds familiar! It is under the dash on the passenger side by the kick.
Rob

...I am going to be pulling the codes soon, and will post the results. Since sometimes the engine light intermittently comes on I will try to get diagnostics with the engine light on, and off.


As I posted, there is a high possibility that '94 is OBD2...so the light trick would not do it....ANyway, I'm told AUtozone will read the codes for free...
However, suggestion about the pump relay must be considered..and several relays are completely identical..so you can just switch relays one for the other to see what happens at no cost.
ABout the engine light that goes on and off, fualty EGR valve is a common issue.
Waiting for your findings

EH Big L, that Grand PRix is awsome....

My girlfriends Bonneville does the same thing. It basically just shuts down while either driving or stopping. When it shuts down all of the dash lights go on, car stops and when you restart the car you need to reset the clock and radio. Its almost as if someone pulled the plug. No warning what so ever.

Any help is appreciated. I did check for codes with my Auto Scan 6000 and there were NONE.

I have cleaned and tested the battery and terminals.