QuestionHi there This van has 170k miles & a 80k mile history of uneasy flow (accelerator not steady)during trave @ highway speeds even w/ CC on. The van started fine when last driven a 6 days ago. We are the 2nd owners and it was bought w/ 55K on engine.
Actions Taken and Items/Areas of concern Checked.
1)The engine has a good spark. Both plugs & wires were changed this wk & firing order is correct. 2)Checked gas level & tank not on empty (gas added anyway.
3)Starter fluid sprayed into the manifold & would idle/accelerate fine provided u continued spraying. When we stopped spraying the engine died. Fuel filter changed & I didn't prime it, but we've had it running 1-2 minutes at a time w/ the aid of starter fluid. For future reference, should I prime fuel filter during future "tune-up's? The filter changed was near the gas tank. Is there more then 1 fuel filter on this van? 4) We checked to see if power was being sent to all fuel injectors & we noted pwer going to all 6 injectors. We checked these w/pwr meter set on "ohms level" & engine "off". The ohm meter read about "2", almost "2" and finally near nothing. 2 of 6 tested appeared to have the same varriance. Cecking from right middle and lastly left it was weaker @ both sites. Should I be checking them a different way amps/dv volts etc.? Each injector looked similiar to a 6-pack ::: Checked the fuse interior fuse panel and noted to have a few fuses of odd amperage and changed them to their respective amps required. We also checked the "relay fuse center" under the hood & #15 was missing. This relay switch reads "F/P MP SPD CONT" and there is nothing by way of accessible wiring for me to plug in a relay swithch here, although it looks like one should belong there. #14 says its for the "fuel pump". It has power when tested. The guys are in the yard as we speak & under the hood. One just asked me to ask you if there is some sort of fuel pump reset or dump swith? Any other ideas? Thanks much for your or help! Jason Cloud(minnesota)
AnswerHello Jason,
No fuel pump reset on GM's like Ford has.
There is a fuel pump relay that needs to work in order to power the fuel pump.
BUT..there is also an oil pressure switch that powers the fuel pump directly once oil pressure builds to 4 PSI, so the pump should have been running when you were running the vehicle on starting fluid.
There is no need to fill or prime the fuel filter when replacing it. The pump should operate for three seconds when the key is turned to run, or as long as the engine is cranking or running, so that will fill the filter and pressurize the system.
The injectors run on battery voltage, so if you want to check the reading through the injectors with an ohm meter, do so, but have the connector unhooked.
Check for 12 volts DC on one of the wires to the injector when the key is in run.
When the engine is cranking or running, the ECM pulses ground to the other wire.
A "noid" light, available at parts stores, will blink when connected to the injector wire, and the engine cranked.
If you don't hear the pump running in the tank, check for voltage back at the connector. You need to check the larger wire, 12 volts. The smaller wire is fuel gauge sender wire.
You might get back under the fuel tank if you can't hear the pump come on, and just as someone turns the key to run, smack the tank with your hand, right under the middle. It could jar the pump loose and make it run. Works sometimes.
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