Engine cranks but will not start

IGNACIOCORIA

MEMBER
2007 CHEVROLET TAHOE
5.3L
V8
2WD
AUTOMATIC
220,000 MILES

So i'm not sure if my problem is electrical or if it's something to do with my fuel system. When I insert the key and turn it to the on position some times I can hear the fuel pump turn on but only on the first time. If I try to open the switch again I can no longer hear the fuel pump. I checked all of my fuses, fuel pressure and everything seems to be fine, but when I try to crank the engine I have no spark in my coils. Spark plugs, wires, the throttle position sensor, those are all new. I also bought a new battery. My truck was working just fine but just pulled up to a gas station to fuel up and from there it just didn't want to start no matter what I tried. So please if you can help me out and have an idea of what it could be let me know. I need to get it running again. It is my work truck and I haven't been able to work because of it. Thank you

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

So if you turn the key and the engine only cranks but does not start then we need to start with fuel and spark.

Here is a video that will help with this issue and get us started:

https://youtu.be/dCjmRL3p4Cs

However, if you checked the fuel pressure, what was the PSI when the engine was not starting?

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Also, how did you check for spark to see that you were not getting spark? Did you pull a plug or wire and hold it against the block and crank the engine?

If you don't hear the fuel pump and you don't have spark then we could have an issue with the crank sensor.

https://www.2carpros.com/articles/symptoms-of-a-bad-crankshaft-sensor

I am attaching the info below from the manual on how this works but if you are not getting fuel or spark then the crank sensor would be the first place I would look.

Let me know about this info and we can go from there. Thanks

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