1994 s 10 P/U 4wd 4.3

Can anyone tell me the pro and cons of complete spider assem. replacement versus regulator replacement. Thanks
KJR

If you replace the entire assembly when only the regulator is bad, you just spent a ton of money, needlessly. Guessing will eventually fix the problem, but it can get very expensive, very quickly when you guess wrong. Proper diagnosis will tell you what the problem is right away and save you time, money and headaches. Checking fuel pressure and leakdown will tell you if the fuel delivery system is working properly or not. Key on, engine off, fuel pump running, pressure must be 60psi to 66psi. After the pump shuts off, pressure must remain above 55psi for 3 to 5 minutes. Post your results.

Thanks for the reply Will try to do this weekend as the Flu bug has hit the home
KJR

Can anyone tell me the pro and cons of complete spider assem. replacement versus regulator replacement. Thanks
KJR

is there a problem with this vehicle?

Hard starts,rough idle and drop in mileage. Suppose to have recent tune up and new fuel pump but not sure how new and how recent

Just did fuel pressure check. Pressure would not even reach 50PSI before pump cycled off and there was no 3-5 minute wait for leak down more like 3-5 seconds before all pressure was gone

Just did fuel pressure check. Pressure would not even reach 50PSI before pump cycled off and there was no 3-5 minute wait for leak down more like 3-5 seconds before all pressure was gone

so get new fuel pump and replace fuel filter...then post back on results..

Excessive leakdown could be caused by the check valve in the fuel pump leaking, or the lines and/or fuel pressure regulator leaking in the plenum. If the leak is in the plenum, it could prevent the pump from building sufficient pressure. If you don't want to guess which one to pull apart, (tank or plenum) you'll need to install a shut off valve in the fuel pressure line that will isolate the pump after it pressurizes the system. If pressure holds, the pump is leaking. If pressure drops, something in the plenum is leaking.

would it also work to pull the plenum and cycle the pump and see if raw fuel leaks from anywhere. Also a side note found out pump is approx. 4 years old with about 55000 to 70000 on it and it is extremely loud when running and now can hear a kind of hissing noise like a slow leak in a tire. Thanks for all of your help and will keep you posted
KJR

Yes, you can remove the plenum and cycle the pump. If your leakdown is as bad as you say it is, you'll see the leak, no doubt! Make sure you shield your eyes, No trouble lights nearby and NO smoking! If you don't see a leak, it's the fuel pump.

would it also work to pull the plenum and cycle the pump and see if raw fuel leaks from anywhere. Also a side note found out pump is approx. 4 years old with about 55000 to 70000 on it and it is extremely loud when running and now can hear a kind of hissing noise like a slow leak in a tire. Thanks for all of your help and will keep you posted
KJR


you need pump for starters and fuel filter as well. then jack up front end and remove plugs inspect/replace and use ohm meter to measure resistance of wires...check coil and wires at coil make sure coil is clean no carbon tracking use silicone dielectric grease in the spark plug wire boots... if you replace wires measure new wires before installing....torque to 15ft lbs the plugs....check all those vacuum lines esp the ones at base of throttle body/PCV valve/hose.....carefully inspect those vacuum lines mounted at firewall.....this is the age they crack and leak.....my son has 94s10 pu 4x4 5sp.. runs great 4.3l

Thanks to all that have posted I will be posting outcome hopefully this weekend . Again thanks
KJR

New Update. Regulator was leaking while taking the unit out busted two sets of poppet ears will be replacing CPI. Plan on changing nut kit since there is a spot almost rubbed through but torx bolt is stripped any suggestions short of lower intake removal. Will also be replacing cap ,rotor,plugs and maybe wires