Pontiac Repair: 1995 Pontiac Transport 3.8 - engine misses, crank sensor, pontiac transport

Question
Hi, Todd.  Being married to a mechanic, I find myself seeking answers to fix my own vehicle quite often.  About a month or so ago, my van started running really rough.  It sounds like it misses, and when I push the accelerator to the floor, it has NO power, misses and backfires. It only does this "whenever it feels like it" but is happening more and more frequently.  When it started, I thought "bad gas" and fuel treatments helped, but not anymore - I've added treatment with almost every tank of fuel.  We replaced the plugs, wires, and coil, and my husband said that the old plugs still looked brand new.  He dropped the fuel tank and replaced the pick up screen, but he said on inspection, that it didn't seem to be dirty.  Today I noticed that it ran horrible when it was first started in the a.m., when it was cold.  Then it ran fine for a while, until I hit a bump (at slow speeds through the city), it started missing again.  I stopped, shut it off for a second, restarted, and ran fine all the way home.  My hubby says the code reader he has is not picking up any codes.  Any suggestions?

Answer
Hi Kelli:

I would say you have an ignitions system issue going on here possibly a bad ignition module or a bad ground going to the module. That engine has a big stud under the ignition module that has ground connections on it make suree all the wires are clean and the connection is tight as well as any that may be on the transmission to engine mounting bolts. It's starnage that a bump made it run  poorly.. You may want to hav you husband tap on the crank sensor witha long screw driver while the engine is running and see if it misfires or stalls you have to be careful not to bang on it to hard  and the drive belt is in the way too so that makes things challenging so BE VERY CAREFUL! You could have an injector issue as well that vinatge van had a lot of engine control module issues possibly it's dropping an injector out.when it's running rough and misfiring you can check to make sure you have injector pulse on all 6 injectors with a noid light of a computer safe test light... good luck :)