08 Silverado 1500 cranks but won’t start

Went over a huge bump and the entire dash lit up and stayed that way until I got home. After that, the truck wouldn’t start again. It cranks but doesn’t start.

I can, however, get it started by commanding it on with a scan tool.

So far, I’ve replaced:
-Igniton switch
-Fuel Pump
-Spark Plugs
-Fuel Pump Control Module

No further codes or errors are showing with one exception: impact sensors. (Which are cracked in half) I’m not sure if for some reason that may be part of the issue but I doubt it.

I’m hoping for some advice as I’ve really run out of ideas from here. Thanks in advance!

Do you see a crank sensor signal on your scanner while cranking the engine?


When cranking I am getting an RPM reading

Maybe if the computer senses a severe impact (e.g. from the impact sensor) it automatically turns off the fuel pump. To minimize the chance of a fire after a crash.

A cranks ok but won’t start condition is usually either no-spark, or no-fuel. Are you getting a visible spark at a spark plug during cranking? Is the fuel pump running?

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Why would you replace all those unrelated parts before finding out WHY your car won’t start? I don’t know my way around Corvettes and never had or worked on a car with Impact sensors, but If I had your situation, I would have made the choice of 3 options. Replace the impact sensors or find out what the consequences of cract impact sensors are or take the car to a mechanic that knows.

Your car is trying to tell you something, why aren’t you listening?

Why did you not determine if you have fuel or spark before replacing parts?

Just curious, why do you think OP’s vehicle is a Corvette? The post title references an 08 Silverado. Am I missing something?

Re-reading the posts, I have no Idea where I got that from. All I can say is all Chevies are much alike4 to me. I owned one and I will never own another. There was one that made me smile though. I was visiting some relatives in East LA 30myears ago when I saw a l;owered mid 70s Chevy. Lettering in the back window said TCHEBBIE! TSHARP1

I suggest you verify that the plugs are firing when you crank the engine. If that is good then try spaying a little starter fluid into the intake and see if that makes the engine fire up. The results of those tests should tell you what needs to be looked at.

What are you commanding on with the scan tool?