Crank-No Start 99 Tahoe 4x4 5.7 - SOLVED

[j91z28d1]

yeah, check fuel pressure, run a gauge up under a wiper blade so you can see it. that sounds like slow to pump up fuel pressure and then when it does, you're in part off he crank routine that it's flooding.

try cycling the key a few times only to on, not crank to build some fuel pressure before your first crank attempt.

after that, cap, rotor, and if not done in a while plugs and wires, with good parts. caps have always had a bit of a short life for me. I would buy them 2 at a time and toss one in the back for a spare.

 

[no cigar]

@strutaeng

Hook up a fuel pressure gauge and report back:
A. Key on, engine off: pressure? 58/60psi
B. Same as above after 5, 15 minutes? 58/60psi
C. Engine running: pressure? Never got truck running but cranking psi still held around 58/60

 

[east302]

Pressures look good and it doesn’t look like you have a leak. Spark and compression would be next unless it has some codes stored.

Check for spark (and compare quality of each) on all eight, but shotgunning in a Delco distributor cap wouldn’t be a bad idea. I had a bad (new) off brand cap that misfired one plug. Unplugging the offending spark wire actually allowed it to start.

Someone mentioned it earlier, but holding the gas to the floor temporarily stops injector flow. If that works, check the output of the coolant temperature sensor (by the thermostat) with a scanner. If it’s flaking out, the computer may call for too much fuel.

 

[no cigar]

Hey guys, little update here. Still having the issue but the truck has been sent back to the mechanic.

Compression is all good. Around 150 psi on 6 cylinders with two others down around 130-135. All seems to be good there. Is getting good spark and also fuel as well. There is noticeable sputtering and backfiring when trying to start it so he is thinking timing. He's confirmed the engine is timed properly and all the marks are lining up. I believe he's going to replace distributor entirely and if no luck then - move on to timing chain.

 

[strutaeng]

Hey guys, little update here. Still having the issue but the truck has been sent back to the mechanic.

Compression is all good. Around 150 psi on 6 cylinders with two others down around 130-135. All seems to be good there. Is getting good spark and also fuel as well. There is noticeable sputtering and backfiring when trying to start it so he is thinking timing. He's confirmed the engine is timed properly and all the marks are lining up. I believe he's going to replace distributor entirely and if no luck then - move on to timing chain.

Distributor is a possible culprit.

I now see your fuel pressures: those look good.

Still not sure what to make of that odd sound while cranking though...and the compression numbers do look a little low on those 2 cylinders, but not low enough where it wouldn't fire.

Thanks for the update.

 

[exp500]

Here are a couple parts that have worked well for me in the fleet. -

More Information for UNITED MOTOR PRODUCTS DCR820X

More Information for UNITED MOTOR PRODUCTS 9362

When adjusting distributor timing, hold rpm around 1200 steady read scanner cam/crank correlation or whichever your scanner shows. Book calls out 0+- 2 degrees at over 1000 rpm.

 

[no cigar]

I'm happy to report that the issue was the dizzy. Truck has been running for about a month now.