Chevy & GMC Vans

I had my altenator changed out by the GM dealer last week and have had the van back to the dealer the same day for stalling. They had it for 4 days and checked everything. I picked it up on Friday and on the way home it stalled. You are just driving along and all of a sudden there is no power and the check gauges light comes on and you can then put the van in netural and re start it. Anyone have any problems like this.

Well I have been reading everything I can about this problem and found this on another site.

http://www.automotiveforums.com/vbullet ... p?t=172879

Will have to look behind the battery when I get home after work.

The only difference is your going to bee looking at the black fuse box under the hood. GM moved that box from behind the battery. It does sound like a connection is dirty. Make sure you check both positive and negative connections on the battery and where it goes to the body.

Well got home and installed a new battery. Took off and cleaned every power and gound from the battery and the underhood fuse box I could fine. Turned on everything I could fine in the van that uses power and let her sit there. Everything fine. Took her to the highway and took her for a good run and everything held together. Now I will give it back to the kids to use and see what happens.

Good luck, Pete!

Thanks Peter. I need all the luck I can get. When the GM dealer tells you they can't find out why it is stalling after having the van for 4 days you start to think what can I find that they didn't.
They tested the fuel pump and filter and all the other common stuff. The van didn't not show any codes. They tested just about everything the service manager said. All for no charge because they cpuld not tell why it was stalling. He even took it out on the highway and it stalled on him. No coughing or sputtering just nice and smooth no power. Turn the key off and restart and go a little bit longer and it would do it again and again. We picked it up Friday afternoon and made it home without stalling. Went to Canadian Tire in the morning and on the way home bingo dead. Son took it out Sunday and same thing. So I start to change parts and clean grounds and power wires where they conect to parts. And see what happens.

The pick-up coil in the dissy? Mount a mechanical fuel pressure gauge outside just rear of the hood. I had a buddy who had a problem like that and the truck would just die. I mounted a fuel gauge outside the hood (for safety reasons, do NOT mount inside) and he watched the gauge when the truck started stalling. It was the fuel pump that was crapping out intermittently. 3rd one in 5 years.
Heck, mebbe v8famvan has a coupla ideas...?

Gm mounted a pressure gauge inside with the dog house off and said everything was fine. That when it stalled the fuel pump was putting out just fine. I was think that if anything they would have hit me for a fuel pump because of the cost but did not. I even asked him to change the fuel filter and he said it was fine. So I feel better that they didn't start just changing parts for the hell of it.
I have been so busy with the heat we are having I am hardly home anymore to work on the van. Or anything else that is.

Hi PeterT
Hmm, that's definetly a "Hard Stall", Fuel or Electrical would be my first thought (Maybe in the HT section IE: Module, Coil or maybe even ignition switch). Does this problem happen in both Cold and Hot phases of the motor? Or just in the Hot (Warmed up) Phase?

The times it has stalled on me was after it had been running for awhile. The dealer had left it over night and it stalled as the drove it into the shop. I just got home and the van has not moved everyone does not trust it now and keeps taking the wifes car. I will have to take it out and give it a good long drive and see what happens.

My only experience with something like this with my 97 was the fuel pump. The first thing my tech though it was is the wires back to the fuel pump as they can corrode and short out, but mine turned out to be the fuel pump.

Since you know it isn't the fuel pump, that would leave electrical, but I have no idea what it could be.

The funny thing is neither does the GM dealer who had it for 4 days. Now that is scary

Hi PeterT
Still doing it eh? Hmm, Peter this needs to be closely monitored. When you go out and fire it up just turn the ignition in the "On" position and "carefully" observe what lights come on in the Instrument Cluster. When the stall happens and the lights come back on as you mentioned, "Carefully" observe what lights are now on in the Instrument Cluster, they should be the same lights "On" for both situations. This is a "Hard Fault" which shuts the motor down when it happens so (personally speaking) it shouldn't be that hard to narrow down Fuel or Electrical. A fuel pump won't (or usually doesn't)
act like that, either it works or it doesn't. This sounds more like a loose power or ground wire or a Fault in one of the HT units Module or Coil or loose wires around it, that's the only place the shut the motor down like that in one swoop sort of speak. Even a Bad Distributor Cap can cause this but nothing else past that point, if it was fault after the Cap it would be a stumble on a cylinder or two, so it's definitely in the HT section somewhere if you recently replaced your fuel pump (I feel) and would be the next place to check. If you can get a hold of a timing light and hook it up to one of the spark plug wires first and drive around until it stalls, you should see it with the light if it is electrical. If it is then the next step is to hook it up to the coil wire and see what happens when it stalls again. This should definitely narrow it down to Cap or Coil/Module. If everything checks out their with no loose wires and no module or coil faults then your going to have to look at a possibility of an Ignition switch fault, that's why I asked you to Carefully observe the instrument cluster in both phases of trouble shooting because it should show up their. It sounds like a lot Peter I know but in order to narrow this problem down that's what needs to be done. Ya know, the more I think about this, I need to ask you, is that an OEM Distributor Cap you have on? If not then I would have a good look at it first. Also did you switch over the fuel pump relay with the A/C relay? they are the same
to make sure it isn't a relay fault? I mentioned that a few days ago. Hope this helps Peter please keep us updated. Thanks

If you are still having problems I had a truck when I was at the chevy dealer that would just kill. It had been to 5 other dealers. I called GM tech support and had them fax over the file. It was like a book, I couldn't believe how many parts had been thrown at it, including about a dozen oxygen sensors. If someone can tell me how an oxygen sensor can make an engine stall please let me know.

While waiting for the fax I test drove it as the problem was very intermittent. I got lucky and it did it! If you watched the tach you could see it be pulled right to zero very quickly. After about half an hour poking around and taking some measurements, I found a bad ignition module. If I tapped it just the right amount in just the right spot I could kill the engine every time. There must have been a crack in the board inside the module and the right frequency of vibration must of caused an open circuit or a short to ground. I have never seen another one like this.

But you might want to tap (gently) on that ignition module
What have you got to loose.

BTW - I'm resisting the urge.... Don't get me started on incompetent techs and service departments. If you think I'm long winded as it is you don't want to read one of my rants.... I have been trying to be a good boy and have thus far resisted reading that Fram filter post.... Maybe I should do a little cutting and take some pics when I get time next month

Well since I installed the new battery and cleaned every power and ground wire I could fiind under the hood the van has not stalled. My son has been driving it to work and all is well. He has just gone to Burlington with it by the highway and am waiting for his report. No phone calls yet so all must be well. Thanks for all the pointers and I will keep you informed if this problem comes back.