It started out as just small and barely noticeable momentary drops in the rpms while accelerating but eventually progressed to the car bucking and jerking as I accelerate from a stop. Then, one day, it straight stalled out in the middle of the city and wouldn't start. After it cooled down, it started back up, and I was able to get home. We thought maybe the coil packs were bad and causing a misfire, so we replaced them. it seemed to work at first, but after I drove it a little bit that day, it began going back to the usual bucking and carrying on under acceleration. (Note that it would only do this from a stop to about 50 mph. After it reached that speed, the bucking would stop) Also, it would sometimes drive normally. It almost seemed like it only started doing this after driving for so long or getting hot enough. Then, we replaced the ignition control module, and it got way worse. The bucking became more sporadic and the rpm gauge jumpy. Put the old ICM back on to see if there was a difference, but the same thing was happening. Another thing to note is that we replaced all the spark plugs, spark plug cables, and gaskets in the engine. It runs completely fine while idling and will rev up well while in park, and there doesn't seem to be any check engine light.

Feels like a crank position sensor (or the wiring to it) issue.

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WHITE WHINE - 1992 SSE Supercharged 236.26 ci (.040 Over) 15.090 at 90.2 MPH on old engine w/ slipping trans & melted O2 sensor - Gen 3 M62 and matching TB, Gen 2 Pully, Zillamotorsports Ported LIM, YT 1.72 Roller Rockers, SII FPR & Injectors, Hypertech Thermomaster chip w/ 160 Thermo, TransGo Shift Kit, Infinity/Pioneer Speakers & a 10" Alpine Type R Sub, all the watts, 140 amp Alternator, Ricepipe CAI w/ heatshield, Pilot Angel Eye Foglights, Clear Corners, '02 17" Chrome Bent 5's, Magnaflow F-Body Muffler and Hi-flo Cat, Ceramic Coated Ported Exhaust Manifolds, Fan Override, Monroe Reflex struts, red calipers
2009 G8 GT - Sport Red Metallic, loaded, SOLO Axlebacks, Rotofab Intake, Tuned, autodim mirror, removed intake manifold cover, HSV GTS triple gauge pod, two tone red-hot shifter and HSV SuperSport steering wheel, GXP rear sway bar and diffuser, 3.45 diff and various Camaro suspension bits, LED Taillights

Wouldn't the car engine not run at all if the crank sensor were bad?

Depends on the failure. Granted it was an older version, but mine died in an intermittent fashion. It would run fine, or it would be jumpy, or it would not run at all for short periods.

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WHITE WHINE - 1992 SSE Supercharged 236.26 ci (.040 Over) 15.090 at 90.2 MPH on old engine w/ slipping trans & melted O2 sensor - Gen 3 M62 and matching TB, Gen 2 Pully, Zillamotorsports Ported LIM, YT 1.72 Roller Rockers, SII FPR & Injectors, Hypertech Thermomaster chip w/ 160 Thermo, TransGo Shift Kit, Infinity/Pioneer Speakers & a 10" Alpine Type R Sub, all the watts, 140 amp Alternator, Ricepipe CAI w/ heatshield, Pilot Angel Eye Foglights, Clear Corners, '02 17" Chrome Bent 5's, Magnaflow F-Body Muffler and Hi-flo Cat, Ceramic Coated Ported Exhaust Manifolds, Fan Override, Monroe Reflex struts, red calipers
2009 G8 GT - Sport Red Metallic, loaded, SOLO Axlebacks, Rotofab Intake, Tuned, autodim mirror, removed intake manifold cover, HSV GTS triple gauge pod, two tone red-hot shifter and HSV SuperSport steering wheel, GXP rear sway bar and diffuser, 3.45 diff and various Camaro suspension bits, LED Taillights

Same problem with my 2000 Bonneville. Replaced crank position sensor and does same thing. Replaced MAF no change. It seems when it hits normal operating temp the bucking stalling etc begins and car won't start til it cools down. Tried replace egr no luck. Anyone have any ideas?

For me, this has always been an issue with something in the ignition system.

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-Car Guy Carl
"Penelope" - 2003 SLE - 247k Miles
"Sydney" - 2000 Honda S2000 - 98k miles

I've had this happen and as simple as it sounds, I had a bad spark plug wire.

Yeah, mine was a coil pack issue when something similar happened. Most expensive ignition piece would be the ICM (Ignition Control Module), so I'd start with the cheap stuff first. Lol.

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2003 Pontiac Bonneville SSEi (L67) - Galaxy Silver Metallic
1996 Chevrolet Camaro (L36) - Sebring Silver

Come on people learn to read, He has replaced: Spark Plugs, Wires, Coils, ICM....so telling him to re-replace these things without proof they are bad out of the box is a waste of his time and money.

Sir, My best guess from the symptoms and given what you have already changed is either a faulty Crank Sensor (like JWycoff stated) or Cam Sensor, or the wiring to them. Sensor's are weird they can fail straight away or they can slowly die and cause intermittent issues like you are having.

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2003 Pontiac Bonneville SSEI
3.8L V6 SC, 180*T (Drilled),
Custom PCM w/Perf Shift,
SLP Ceramic Coated Headers,
Thrasher Cold Air Intake,
GXP Tails, Interior Door handles, Trim pieces etc.
40th Aniv Grand Prix GTP Wheels (Very Shiny & Very Annoying )

You should take your own advice before scolding others, "learn to read". An old post was bumped from 8/2020

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2004 Bonneville SE 151,xxx- 20% tint all around, 5% tint bar on windshield | 4500k DDM HID low | De-badged | Hardwired Passport 9500ix | FWI(inter-cooler piping) | FE2 Rear Sway Bar | Solid Motor Mount | 180* Stat | Firm Shift Kit



- '92 Bonneville SE - '85 Grand Am - '73 Catalina - '67 Catalina
- '87 Bonneville SE - '82 6000 - '78 Catalina [/color]

I had this same issue just recently. My fix was pretty easy and straight forward.
Long story short, I had just replaced the coil packs, plugs, and wires when it started. Turned out, that when I put the new coils on, one of the holes holding the rearward most ignition coil down had been stripped out. I thought that I had got it tightened down, but apparently I didn't. My fix was to take a zip tie, remove the bolt from the stripped hole, and zip tie it down. That restored my lost power, and stopped the stuttering/bucking/engine dieing. That's been about 2 to 3 weeks ago, and still no sputtering on my acceleration