Hard Starting Tahoe

[ctlogistics]

2003 Tahoe 5.3 Flex 201000 miles
Having a hard time starting my Tahoe. It will crank and then fire up enough to disengage the starter, then dies. If I leave the key in the 'on' position for about ten seconds it will start on the second or third try. I already replaced the fuel pressure regulator and that seemed to make it worse. One more thing I noticed, when it does start there is a strong odor of gasoline. However, I don't see any leaking of fuel anywhere.

Update: This morning it wouldn't start at all, just crank. The fuel gauge read a little less than half. I added about three gallons and it fired up on the second try. (It never starts on the first attempt.) Got a fuel pressure gauge at Autozone and hooked it up. First read with vehicle on, but not running was just under 10psi. While running it stuck right at 38psi - no variance. Shut it off and released the pressure and turned back to the 'on' position - 0psi. No matter how many times I tried 0psi in the on position. It would still start and read 38 while running, but nothing when just turned on.

Thanks for any help,
JT

 

[SLCHOE]

2003 Tahoe 5.3 Flex 201000 miles
Having a hard time starting my Tahoe. It will crank and then fire up enough to disengage the starter, then dies. If I leave the key in the 'on' position for about ten seconds it will start on the second or third try. I already replaced the fuel pressure regulator and that seemed to make it worse. One more thing I noticed, when it does start there is a strong odor of gasoline. However, I don't see any leaking of fuel anywhere.

Thanks for any help,
JT

Sounds like the intake manifold gaskets are leaking.

Check the fuel trims. They should be +/- single digits. I'm guessing they are in the +20 area STFT.

 

[ctlogistics]

Thanks for the advice. The only fuel trim I can check is labeled as 'Short Term Fule Trim' on my scanning tool (ODB DroidScan). I'll look at that tomorrow.

Thanks again.

 

[SLCHOE]

Thanks for the advice. The only fuel trim I can check is labeled as 'Short Term Fule Trim' on my scanning tool (ODB DroidScan). I'll look at that tomorrow.

Thanks again.

You should have both. It's generic OBD2 Data and it is all usually there.

 

[ctlogistics]

Stft 3% ltft 4%

 

[SLCHOE]

Stft 3% ltft 4%

Those trims look good.

Your fuel pressure should be 55-62 psi KOEO (key on engine off) and 48-54 psi running. Your running PSI is low and the fact that you don't get any pressure KOEO is not good. Looks like a weak pump.

 

[ctlogistics]

Thanks

That's what I was afraid of. At 203000 it was bound to happen. Thanks for all of your help.

JT