1983 240DL New in tank fuel pump still won't turn over

Post by **98T5** » 19 Apr 2014, 18:59

It appears to "crank" for about 3 seconds then dies. as if it's getting fuel to the throttle body but not sustaining it. I've checked all the following with good results:

1. New in tank fuel pump installed as mentioned.
2. Fuel pump relays (2) both "click" when I turn the car over
3. Main pump works fine. I can hear the "buzz" under the car.
4. Ignition switch turns over nicely
5. Starter engages fine.

I made sure the pump worked by testing it before I dropped it in. So what do you advise as my next move?

I was thinking fuel pressure regulator?

Also, How can I check the FPR for failure anyway?

*sidenote - the night the car died I it was running fine. I went into the Walmart and came back out and the car would not start. I thought it was flooded but after running the test. I realized it was the in tank pump so I had the car towed to the house.
*(Thanks GEICO!

)

Any advice is appreciated. thanks.

lummert · Post by **lummert** » 19 Apr 2014, 21:36

In tank pump wired correctly?

Post by **98T5** » 20 Apr 2014, 08:57

lummert wrote:In tank pump wired correctly?

Yes I matched the positive wires with the "+" and "-" on the pump. and when I tested it, it came on and appeared to suck "in".

Please don't tell me the pump is reverse polarity?

I read online that the new SENDERS being shipped out were wired backwards but not the pumps. My sender is not new and is in great shape for it's age.

Post by **98T5** » 20 Apr 2014, 11:26

OK, I took the pump back out and swapped the wires on the pump, put it back it, turned the key to position #2 and let the pump prime up a minute or so and still nothing.

any other tips?

can fuel pump relays be faulty even if they "click" ?

Post by **98T5** » 20 Apr 2014, 14:47

Almost certain it's the FPR. no fuel squirting from the FPR line when I undue the hose on the back of it.

Post by **98T5** » 21 Apr 2014, 05:08

Update:

Getting fuel all the way up to the fuel rail. stays cranked for all of 10 seconds and dies. I think it's thr FPR and go from there.

Post by **98T5** » 25 Apr 2014, 20:35

It's a dead IAC.

Post by **rgk** » 27 Apr 2014, 08:18

I'm a little late on this, but one way to test a dead IAC is to apply throttle right when the car turns over. If it runs until you let off the throttle, the IAC is suspect.

Post by **98T5** » 06 May 2014, 19:10

rgk wrote:I'm a little late on this, but one way to test a dead IAC is to apply throttle right when the car turns over. If it runs until you let off the throttle, the IAC is suspect.

that's exactly what's happening. I pulled one from the junkyard. about to go clean it up and see if it does the trick. thanks. I kinda felt I was headed in the right direction.