Weak fuel delivery? Crank but no start. Ran fine yesterday...

[Eicca]

So my mom called while I'm at work: "Help! My car won't start!" etc etc etc.

Thing is, I drove it last night and it ran fine.

Jumped in and tried to start it. It cranks strong but doesn't catch. Doesn't sound like ignition is happening.

Spark tested positive. Fuel came out of the filter when cranked with the line disconnected, but it seemed like a slow trickle to me. Fuel filter was changed last year.

Swapped EFI fuses with no result. I assume the MAF is good, judging by the 80-series behavior of crank-catch-sputter-die when the MAF is bad.

The interesting thing was, after playing around with the fuel line and hooking it back up, it sputtered and even caught and ran for about two seconds, then went back to the old crank-but-no-catch. Seems to me like the fuel built enough pressure in the lines to sustain life for a few seconds. This also tells me nothing is wrong with the immobilizer or EFI.

This leads me to suspect the fuel pump, given the sudden nature of the failure. Is it possible a connection came loose, causing insufficient power? Or is it more likely the pump itself failed?

How much is a new pump anyhow?

 

[Eicca]

Update/bump: definitely low pressure in the fuel lines. When I disconnected the hose, it did not spurt. It just dripped.

 

[Trunk Monkey]

Check the fuel pump. Easy access.

 

[Eicca]

I know it's pumping, is there a way to make sure it's putting out enough pressure? Do they make fuel pressure gauges?

 

[hankinid]

I know it's pumping, is there a way to make sure it's putting out enough pressure? Do they make fuel pressure gauges?

Any small gauge should work...hose barb on the end to fit a short length of rubber hose to fit the fuel filter input. If you do replace the pump, you might also replace the filter.

hth

Steve

 

[Eicca]

Another clue to the case: she told me that it's been occasionally reluctant to start for about two years now. Def sounds like the pump.

What kind of pressure reading should I see when I test it with a gauge?

Also, during my searches I ran across something called the "fuel pump ECU." What is that, and how do I test it?

 

[CappyKD]

Another clue to the case: she told me that it's been occasionally reluctant to start for about two years now. Def sounds like the pump.

What kind of pressure reading should I see when I test it with a gauge?

Also, during my searches I ran across something called the "fuel pump ECU." What is that, and how do I test it?

Both test procedures are available in the FSM which can be downloaded via links here on Mud.

 

[Eicca]

Downloaded the 2004 FSM but the pages are all kinds of out of order and it's a pain to read. Any other downloads out there?

 

[Eicca]

Also, checked resistance across terminals 4 and 5 of the fuel pump. 2.88 ohms. FMS says normal is between 0.2 and 3.0.