1993 Trans sport 3.1l

[Chuck Bush]

I am getting a trouble code of 33. I see that deals with the MAP sensor, does this mean that I need to replace my MAP sensor? The van sometimes will stall after starting, I can always keep it running by fanning the gas peddal and the idle will eventually correct itself. This problem seems to happen when the van is not parked level more than any other time.

[96tsport]

Might try this first.

[Chuck Bush]

I had already replaced the MAP sensor before I got a reply. The engine now starts and does not stall but it does idle rough, but only when warm. Pressing the gas pedal will correct the rough idle, so what do I check next?

[96tsport]

Always good to rule out basics. How are the spark plugs, wires etc? I'm assuming there are no more codes.

[Chuck Bush]

Correct no more codes, I will check the plugs and wires. The van was a gift from my parents, they tell me they just had a tune up done less than a month ago but I have a feeling they mean an oil change. Will post again after I check plugs and wires.

[Chuck Bush]

OK, plug wires were probably the originals from the factory as they had the numbers on them. I replaced wires, plugs, distributor cap and rotor, pcv valve and air cleaner. Idle is still a little rough and now I am getting a code 33 again, this is with the tune up and a new MAP sensor last week. I am about ready to just take it to a mechanic unless someone has an idea on what the problem could be now. I did recheck all of the vacuum lines and they all seem to be hooked up and working properly.

[96tsport]

Code 33 shows:
Check the vacuum hoses from the MAP sensor. Check the electrical connections at the ECM. replace the MAP sensor.