2007 sierra wont start just turns over

dwalters198016 · February 12, 2015

hi all

I have an 07 sierra new body style with the 5.3 liter. I don't drive it much in the winter so I start it up every couple days to keep things moving around. I went to start it the other morning to take it out for a spin and it just turns over and over. I tried to plug in the block heater and after a couple hours it tried to start once and that was it. its been really cold here I was wondering if its possible that it could of froze? its tuff to here the fuel pump going im not really sure how loud its supposed to be. any help or thoughts would be much appreciated.

SILVER SLED · February 13, 2015

Try spaying starting fluid in the intake track somewhere. If it sputters an runs for maybe a second, you aren't getting fuel. If nothing changes, your prob not getting spark. You can then diagnose from there.

dwalters198016 · February 13, 2015

ill give that a try, I thought it might have froze over, I didn't think that was possible really. I grabbed a couple of battery warmers today and put them over the motor, is it possible that the fuel pump just up and quit? like I said there was no signs of any running issues before that. Could maybe a relay or the pressure regulator have crapped out? theres one other thing I forgot to mention I had a fault code come up a couple months ago about the crank sensor , I read somewhere that if that goes there wont be any spark. is that true?

oldscsc · February 17, 2015

If the crank sensor fails, the PCM won't command fuel injector pulses or spark. On a scantool live data feed, crank the engine over and watch for an RPM signal. If it has one, your crank sensor is working.