Love my van!! 102,000 miles and just returned to Maine from winter in FL. Ran like a dream up until now. Starts fine, runs fine until warmed up and shut off. When restarting and driving it appears to be choking itself out, lose power, small backfire in carb and then takes off fine. This has happened the last two times I have driven it. I tried dry gas treatment because of freezing temps and still doing it. PCM, catalytic converter, rotor, wires or plugs?? Where would you start to analyzing it? I have not done the keyed code test yet....too cold!. I have about 70,000 miles on plugs, wires and rotor. Thanks in advance for any and all suggestions.

 

If it runs fine except in cold weather its likely to be a problem with the fuel system, otherwise its the PCM. You might try adding gas line dryer or fuel injector cleaner and see if either makes any difference.

 

I have added dry gas to no avail.

 

The next steps would be to test the fuel pressure at the fuel rail and try checking for trouble codes. Backfire through the intake generally indicates too lean fuel mixture or burned intake valve.

If the fuel pump isn't keeping up or is cutting out it will need to be replaced. The injectors could be partially clogged but your symptoms don't really support that diagnosis so its more likely a fuel pump issue. The fuel tank must be kept filled in order to cool the fuel pump, if the vehicle is run for extended periods at low fuel levels (under 1/2 tank) it will permanently damage the pump.

 

Thank you. I will do a code check and get back to you. Also do an injector cleaner too.

 

UPDATE: New plugs, wires, distributor cap & rotor, coil. Van was still cutting out when warmed up. Then is would come out of it and run fine. I decided to replace the upstream oxygen sensor just as part of updating things. I didn't get a chance to hook up the fuel pressure gauge that I had rented from AutoZone before I had installed the oxygen sensor. Took the van for a ride and cannot duplicate the problem I was having. Could it be that the oxygen sensor was my problem all along? The van runs like new again and has more power and does not have any hesitation at all. Just keeping my fingers crossed but wanted to update everyone of this.