5.3L Tahoe hard to crank
#31
Engine running, gauge hooked up, pull the vacuum hose off the regulator. You should see a pressure spike.
If you have a DBW throttle body, you have no IACV. If you have a DBC, it's the small gold round thing on the upper right side. The holes in front of the blade are where the IACV draws from.
If you have a DBW throttle body, you have no IACV. If you have a DBC, it's the small gold round thing on the upper right side. The holes in front of the blade are where the IACV draws from.
Last edited by 99corvette; Dec 4, 2013 at 07:55 PM.
#32
I have been fooled a few times by the fuel pressure regulator. I have pulled the vacuum line off 3 times and not seen any fuel. Pulled it off for a 4th time and there is fuel. Put one on it and fixes the problem. Also you could try unplugging the MAF sensor and starting it up. If it starts up fine then there is your issue. Unplugging the MAF will make it start and run off of set values. If you can I would try to use a scantool and see what your coolant temp reads when cold before you start the vehicle. Kinda sounds like the issue. Usually you would get a code but not always.
#33
I have been fooled a few times by the fuel pressure regulator. I have pulled the vacuum line off 3 times and not seen any fuel. Pulled it off for a 4th time and there is fuel. Put one on it and fixes the problem. Also you could try unplugging the MAF sensor and starting it up. If it starts up fine then there is your issue. Unplugging the MAF will make it start and run off of set values. If you can I would try to use a scantool and see what your coolant temp reads when cold before you start the vehicle. Kinda sounds like the issue. Usually you would get a code but not always.
#34
Maf did nothing to mine. But as I was Tryin mine I turned around hitting the shifter up, started right up. Anyone heard of a neutral safety switch goin out like this? I'll try again in the morning when it's cold and see if I can do it again jiggling the shifter.
#38
Update: rented a fuel pressure checker again. Key turned over just primed and not running got 50psi. Then running got 45psi. Then running with fuel pressure regulator unplugged got 55psi. Sound normal?
#39






