Subject vehicle is a 95 Bonneville SE 3.8 (3800) Non-Supercharged.
Here'* the VIN: 1G2HX52K6S4264365
Results posted at end of this thread.
Purchased the car with 73,000 miles in it in 2004 and up until the the past 30 days had no problems at all. I've got just over 204K miles now and a huge problem. About a month ago I developed this oddball symptom. If the fuel was less than a quarter tank AND I turned Right the car would stall momentarily. Regardless of the amount of accelerator pressing this stallout persisted until the car was righted into the traffic lane. Once done it ran fine. I assumed that the fuel filter was in need of change. Replacing it did not correct the symptom. The symptom continued. I parked the car at work, about 8 blocks from its last Rt. hand turn. This time it sputtered, missed and generally ran rough. When I parked for work was the last time the car has run. I replaced the fuel pump, thinking the strainer or pick-up tube might be having trouble when the gas shifted to one side of the tank on the turns. Turning Left, inclines, downhill, rapid acceleration, nor idle caused the stall, only Rt. Hand turns.
In the beginning I felt this was a fuel delivery issue. A couple of guys from work said the car sounded like it was out of time. Skipping the bloody details here'* what I've replaced in addition to the air, oil, fuel filters. The timing chain and gears (yes it was in time and there was no evidence of wear on the sprokets or chain), the cam sprocket inturrupter magnet (that little booger shot across the room and hid...FYI Use great caution when pressing on this little gizmo. Its small, hard to find, and cost $42 at O'Reilly) I also changed the Cam Position Sensor, Crank Position Sensor and fuel pressure regulator. The check engine light hasn't ever come on but I did rent an OBD scanner and the only thing that it showed was "Throtle Position Sensor-Low Voltage" Not knowing exactly what this meant I also purchased and installed a new TPS. Should have read here first and saved a lot of effort on needless parts. Oh well they are installed and have a life expectancy/peace of mind factor.
Initially the car would turn over but would not start. It would "hit" now and then but not start. This I thik is why the advice from my arm chair quarterbacks was the timing being off. I also replaced the Ignition Control Module beneath the coils. Since I had the car on jack stands and the rear plugs were unusually accessable, I changed the plugs and wires. After doing this the car would crank and run by using a steady supply of carb cleaner/starter fluid down the gullett. Still seems a fuel supply problem.
Now this is where it gets strange. Yes, I did read about the ground busses. As a matter of fact, I checked on them today having read up on them last night. I pulled up the carpet on the driver side along the door and did not find the ground bus. I discovered it forward of the door almost under the kick panel. The bus was taped to the outside of flexable protective tubing and was wrapped with about a half a mile of electrical tape. Checking inside, I found the metal strip to be clean, shiney and free of any corrosion. Checking the passenger side yeilded the same. I brushed both with a brass brush and applied dielectric grease, and put them back as i found them, only with less tape wrap.
I have checked for grounds under the hood. Found one behind the battery with three or 4 wires. Two on the drivers side fender one with a single connection containing two wires and one just aft of that with 3 wires. I cleaned all the connections and greased them. I did not find an engine to chassis ground, or a chasis to frame ground. I believe there is another ground at or near the tranny. I'll look for it tomorrow.
I did manage to find and ultimately destroy a few deterrorating vaccuum connections. The "T" that comes off the throtle and supplies the TPS was crumbling. When I moved it to install the TPS it broke. As did the 90 degree fitting on the Fuel Pressue Regulator.
So many parts of this sound like posts from others, its scarey. Have I put in enough information for anyone to take a stab at where things are wrong? If the voltage at the TPS is low, do you know where the ground is for it? What should the voltage be and can it be checked with a voltmeter?
One other semi unrelated queston. Should there be residual pressure on the fuel pressure regulator? When I depress the valve core there seems to be none if the car isn't being cranked. I think the vaccuum bleed off from the bad connections is the culpret there. Just putting out another grass fire in the forrest fire.
Thank you in advance for any help, advice, comments.[/b]