Chevy Express won't start - again

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Jan 8, 2009
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Texas
Okay, I'm the guy with the Chevy Express 4500 Motorhome and over the last three years I have replaced the fuel pump, fuse box, starter and last month the starter relay. It seems that maybe putting a tarp over it in the hot, humid environment is murder on the electronics.

Anyway, it's back to a crank, no start condition. I don't think the fuel pump is energizing. The two weird symptoms are (1) the key doesn't automatically release the starter when you let go and (2) when you take the key out, the dash lights stay on until you open and close the door. Doesn't seem to fit the symptoms listed on the internet, but what else would cause this?.

Is all I need to do is replace the black box ignition module for $12 or does the key tumbler need to be changed to, since it doesn't release?
 
Burt, check your ignition control module. This is a common failure for GM,s. In fact I would keep a spare and the tools to change it.
 
Listen for the fuel pump energizing (making a buzzing or whistling) when first turning the key to run. No sound? Pound on the bottom of the fuel tank, try it again-if it comes back, there could be a bad connection, or the new pump could have failed. The failure of the starter releasing could mean ignition switch trouble too.
 
With a consistent crank but won't start, run the basic fuel, spark, timing, compression troubleshooting drills that apply to any car.

Someone in your other thread mentioned that software would keep the starter turning until it starts, even if you let go of the key.
 
I had a 99 Express and the crank no start was usually a crank position sensor. If you don’t hear the pump it may not be your problem but that was mine. It would set a code for crankshaft position sensor circuit fault. I carried a spare and a ratchet to change it, did one on the side of eastbound I80 about 40 miles from Iowa City. I didn’t have a spare that particular time and a super cool taxi driver actually brought one to me. Cost me around 50 dollars but was cheaper than a tow bill.
 
I am not familiar with that make and model, so this is just in general for trouble-shooting.

Even with todays modern fuel systems, an ounce of gasoline put into the intake ( after the mass air flow sensor ) should make it run for several seconds and then die, if the problem is that it is not getting fuel. If it were mine I would dump about an ounce in the intake after the MAS and put it back together as fast as possible and jump in it and see if it fires up for a few seconds.

I use to just dump an ounce into the carb with the choke plate held open, then get in it and try it. If it fired up and died then it was the fuel system, if it did not then it was the ignition.
 
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Nope. But thanks.
That eliminates a lot. Based on our Jaycee have you checked the wiring to the back? Where they extended ours had a lot potential chaff points. Had to rewrap and put new loom on a few sections. It was on the drivers side on our 05 Express.
 
Post Mortem: It was the $12 ignition switch. Youtube video instructions worked great.
Post Post Mortem: Problem is back. Took it to an RV repair place. They said problem is there is a loose, corroded electrical connection that is dropping the voltage causing crank, no start and increasing the amperage which fries the electronics. Tail lights frequently burning out is the tell tale symptom. wish me luck.
 
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