'97 Voyager - Intermittent 'Buck"

Had a simpler problem back in July...1997 GC w/ 3.3V6. Bucking only occurred on slight up hill grades with the A/C on just at around the speed the torque converter kicks in (approx. 40MPH). Occasionally I would get a pop...pop...pop "backfire" and response delay when hitting the accel heavy when moving slowly to scoot out in front of traffic. Dealer applied a software upgrade to the tranny and replaced the ignition coil (FP-Number:

4443971). Repair was about $300 ($200 parts and $100 labor). Been running perfectly since.

Not sure about Mopars, but I had a 94 Chevy Corsica that was running fine when one day the radio started sounding really crappy while cruising at freeway speeds. In about 5 miles it started running really rough. I pulled over to a gas station to check it out. I left it idling with the windows up (cold outside), the stereo off and the heater running on low fan. I was under the hood looking at my battery connections when I heard the engine speed kick itself up to about 3k or

4k rpm. As I lifted my head up to see if someone was in the car (there wasn't), I heard all 4 doors lock themselves. I looked through the rolled up drivers window and on my parked car (which had just locked me out by itself), the speedometer read about 45 mph. WTF!? Never saw THAT before!

After the car sat there running at 45 mph in park (?!?!), the engine very suddenly died as if you'd just turned off the key. Of course my keys were still in the ignition and the car still had the headlights on. It only took about 2 minutes for the battery to completely die, and as usual, it took almost 3 hours for the tow truck to show up because of rush-hour messes.

The problem turned out to be a bad alternator which overcharged the battery killing the computer module, which by then wasn't sending decent signals to anything in the wiring harness, which then put full output current intot he battery frying it completely and when the ignition thought the car was moving (computer going nuts by now) the door safety locks kicked in. Obviously, this car's speedo doesn't use a cable so when the computer says your doing 45 - your're doing 45. The whole thing resulted in a new alternator, computer & battery. Because the car was still under warranty (about 24k on it @ the time), I only had to pay for the battery (because that's considered a 'consumable'). Electrical problems in computer controlled cars can have a major cascade effect on everything they're plugged into. I don't mean to scare you but since your problem sounds electric in nature and your vehicle has a computer controlling it, get it looked at _yesterday_.

Any service bulletins are available at your dealership with a service department. There may even be a recall (free fix for you). Call your dealer first and ask if there are any recalls or bulletins involving your vehicle and if there are, have them do everything (their dime, your time). If you still have the problem, go to a good local mechanic who knows electrics and have them troubleshoot it. A really good one won't kill you ($$$) for a diagnosis if they can't find a problem that they can see but can't find. If they can't see it, most good ones will try to keep you happy for repeat business by not smacking you for a big diagnostic fee anyway, maybe just charge you about an hour labor or something. If you still have the problem, you're stuck using a dealer to find/fix it. They charge more, but they know more about your car than anyone (at least the Journeymen likely do).

Good luck, - Jeff G

Jim Taylor wrote:

If the Check Engine light came on, a code will be stored. Start there.