96 Chevy s-10 fuel problems
tazman1
09-07-2009, 12:05 PM
when the truck sits for a couple of hours it will not start unless I put a couple of drops of gas down the throittle body. than i can shut off and start as much as I want.untill it sit awhile. The fuel pump is less than a year old and working fine, the filter is new.Is there anything else it could be beside the pressure regulater. and is there a way to test it before removal.it is a 96 vin #X and the regulater is under the top half of the intake. thanks
MT-2500
09-07-2009, 07:15 PM
when the truck sits for a couple of hours it will not start unless I put a couple of drops of gas down the throittle body. than i can shut off and start as much as I want.untill it sit awhile. The fuel pump is less than a year old and working fine, the filter is new.Is there anything else it could be beside the pressure regulater. and is there a way to test it before removal.it is a 96 vin #X and the regulater is under the top half of the intake. thanks
You need to check the fuel pressure when it acts up.
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.
You need to check the fuel pressure when it acts up.
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.
MT-2500
09-07-2009, 07:19 PM
What is the date of manf on door plate?
I only show a X code engine for 1997 up.
I only show a X code engine for 1997 up.
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