99 Tahoe 5.7 only runs with ether shot

[j cAT]

Originally Posted by trox

Got the pump changed out and it started right up. Pressure is 63 with key on engine off. 56 with engine running. I hope that's good. Wait a minute though. Still have a head issue. Water in the oil. Drained the oil and drained the water several times and put the blue expensive stuff in to hopefully fix my problem. Ran for the 50 minutes the bottle called for. After about 5 minutes the water stopped coming from the tail pipe and the oil on the dip stick was looking OK. Gonna drain and refill my oil tomorrow. Let you know for sure if the blue stuff did the trick.

the fuel pressures look good now...so that should be out of the way ..
on the head gasket leak...post results...do compression check...also pressure check coolant system...

good luck

[MT-2500]

Fuel pressure is still not good.
Run the full fuel pressure test.

And watch for coolant in oil.

The only true test on a fuel pump is to check the direct fuel pressure from fuel pump.
A quick test is to block off the return line and see if fuel pressure comes up to 75-85 lbs.
But do not run the pump at full pressure very long.
Also when testing fuel pump and pressure you need to tape a gauge to outside windshield or outside mirror and drive it on the road for 20 -30 minutes
until the pump gets has run a while to check for a pump fading out after hot.

Hard to start cold or hot and fuel pressure testing guide lines.
Check cold start fuel pressure.
Check engine running fuel pressure.
Check engine running on the road fuel pressure.
Then shut it off and watch for fast leak down.
Pinch off at rubber part or block off return line and check full pressure.
If pump has full pressure with return line blocked and low pressure without it blocked most usually the fuel pressure regulator is leaking or not holding pressure.
Later V6 and V8 gm engines should have 60-66 fuel pressure.
Cold start should be 64-65 lbs of pressure.
If you do not have full fuel pressure on a cold start the injectors will not squirt fuel.
Do not leave home without it.
Engine running should be 60-66 lbs pressure depending on engine load.
Full pressure with return pinched off should be 75-85 or more.
And if it has a fast leak down after shut off you have a leak in system.
Post back fuel pressure readings.

[trox]

All is good so far. I put Blue Majic in the radiator after flushing the cooling system several times. Ran it for an hour with clean oil. Drained that oil one more time and after adding new the oil and changing the filter, everything looks good. I don't have tags on it yet but I've run it for a couple hours around the house and out in the field. I need to figure out how the security system works before it locks me out or keeps me from starting. It's after market (Clifford) system. I took it up the road to put gas in it and when I tried to start it I got nothin for 2 tries then it chirped and started. very curious since this is gonna be the wifes ride. Anyway, thanks to all who posted back with help on the fuel pump issue. Oh yea, I forgot to mention, the fuel gauge looks nervous like when I stop it shows the fuel sloshing back and forth in the tank for a while. When it settles, it shows good though.