I have a 96' Plymouth Grand Voyager SE with a V6 3.3L engine. Sometimes I will be driving down the road (interstate above 65 m.p.h.) and the van will just lose power and sometimes it will die and others it will just spit and sputter. The fist time that it did it, I was just driving along and the van just started slowing down and losing power. It started backfiring and wouldn't go. I let it sit for about 10 minutes and it started up and ran fine. The Service Engine Soon light came on. The code came back as "Multiple Cyliinder Misfire". The man at the parts store erased the code and told me to come back if the light came on again. I changed the coil, plugs, and plug wire. This didn't fix the problem. It doesn't do it all the time, usually after driving it for about 25 minutes on the interstate. The light is not coming on now, but it is still doing the same thing. I'm not sure if it would to it on the highway because I'm afraid to drive it due to the fact that I don't want to be stranded. It has done it a total of 4 times all after about 25-35 minutes on the interstate. It's hard to track the problem down since it doesn't do it all of the time. It just backfires and if you press the accelerator it just boggs the engine down even more. Any help would be greatly appreciated.

Your PCM is defective. Common problem, expensive part.

Just wondering if the PCM was the problem. I have a 96 plymouth grand voyager se 3.3 liter and is doing the exact same thing. I've replaced the spark plugs, plug wires, crankshaft sensor, and have a PCM or (engine control computer) on order $200 from Schucks Auto Supply. Anyway, just wanted to know if the PCM was the problem before I spend the money. Thanks

I went through this same problem with an '87 Buick. We bought it from my MIL, knowing that she was having a problem. It would stall at speed, usually willing to restart. While it is not the same vehicle, the principle should be the same. The buick has only 30000 miles--my MIL didn't drive much.

I replaced the crank position sensor. It was a bit better, but not cured. Next I replaced the MAS, the mass air sensor. That worked like a charm. The car hasn't stalled since.

The MAS is very easy to test. It should be located somewhere along the air intake system. With the engine warm and idling, tap the MAS with a screwdiver, or similar, and see what happens. If the engine stumbles, replace the MAS. You don't need to tap too hard, something equvilent to dropping the screwdriver a couple inches onto the MAS.

No guarentee here. There are so many sonsor inputs to the car's computer which will affect things. This is simply the one which cured my problem.

I see this is a continuation of an old post. This engine has a speed density injection system. No MAS or MAF senor on these engines. It sounds like you may have a fuel pump problem. Backfiring and bogging down can be from a lean condition; and set a p0300 code. Buy a fuel pressure gauge and drive the vehicle with it insalled. When it acts up see what your pressure is dropping to. Good luck.

I replaced the PCM or (engine control computer) this weekend and the problem seemed to have been fixed ...but after about 35 miles on the freeway it stalled again. Luckily it was on the exit I was getting off so I pulled to the side of the road (which I'm becoming very familiar with) and let it idle very roughly and backfire a ton and then it was able to drive the rest of the way home. So it's not the PCM, or spark plugs, or wires, or crank shaft sensor. It seems to be doing this only when I'm driving at about 65mph for a period of time. I'm going to go buy a new fuel filter and pump tomorrow and try that. If it's not those I'm at a loss????:banghead:

I've been reading my chilton's manual...would the MAP (manifold Absolute Pressure Sensor) have anything to do with it? The Chilton's manual says that the PCM adjusts spark advance and the air/fuel ratio according the voltage the the MAP is producing. I also noticed this weekend...while putting the PCM in, that there was a crack in the hose that connects to the throttle body...could this be the problem? Not sure if it was there before or if it happened while I was taking it off to put the PCM in.??? Has anybody else experienced this problem with these vans?

I've been reading my chilton's manual...would the MAP (manifold Absolute Pressure Sensor) have anything to do with it? The Chilton's manual says that the PCM adjusts spark advance and the air/fuel ratio according the voltage the the MAP is producing. I also noticed this weekend...while putting the PCM in, that there was a crack in the hose that connects to the throttle body...could this be the problem? Not sure if it was there before or if it happened while I was taking it off to put the PCM in.??? Has anybody else experienced this problem with these vans?
I had a similar problem and the Cam Position Sensor was the culprit... I thought it was weird because I didn't get a code at all.

I just wanted to give everybody an update incase they have this problem with their van, maybe this thread will help?? I'm not 100% sure the problem is fixed but it test drove 30 miles without stalling so I guess only time will tell. I replaced The throttle tube due to having a crack in it...I should mention that I did put high temp silicone on it to cover the hole so I don't think that was the problem, I'm pretty sure I caused the tear when i took it off to get the the PCM. But, I did replace it just to be certain it wasn't getting air in it. I also put higher grade spark plugs in made by Bosch...I started having this trouble 2 weeks after I put in new autolite plugs in (not sure if they had anything to do with it) but I just wanted to be certain this wasn't the cause. (I should mention at this point) Anybody trying to change their own spark plugs on this type of motor...you will need to take off the windshield wiper motor and base so that you can get to that last spark plug that is IMPOSSIBLE to get to. It will take a little time to get it off, but you will save a ton of time in the long run...trust me. Then you can tighten the spark plug to the right tork without guessing. You still will have to go underneath the car for some of it, but it makes it so much easier to be able to put the ratchet on from above and tighten. I also bought a new fuel pump and filter. I bought them all from Schucks and I think I spent about $600 or less for everything including the PCM. I think if anybody has the same problem with their van they should start with the spark plugs, then the wires if they look bad, then the fuel pump and filter. I waisted about $200 replacing the PCM when it wasn't the problem at all ( I guess I have piece of mind though knowing it's not that though) So anyway, for now it seems to be doing well. Please note...if you do plan on replacing the fuel pump...have another person there or 2 jacks so that you can raise and lower the gas tank...it's very hard with the gas moving side to side to get it into position. Also, put a rubber glove over the hole that the gas goes in with a rubber band around it...or you will definately get gas all over the place...I speak from just doing it. Also, there is a retainer ring around the fuel pump...VERY dificult to get off and nowhere except the internet has the tool you need...So I bought the biggest C clamp that schucks had for $9 and broke off the end to one of those wooden paint stir sticks. If you use the stick on the side of the clamp that has a circle that tightens you can get it tight enough to be able to turn the plastic ring. I tried hitting it with a dull screwdriver and hammer to turn it and only ended up breaking a few of the notches. So, anyway hope this helps, I know it would have helped me...so good luck. I'll post more if it starts acting strange again in a few days. Thanks for all the replies!