92Q Will not start - no fuel in the rail

[firstq]

All of a sudden with no warning, my 92Q will not start - arghhh.

The fuel pump was repalced about 11 months ago (perhaps 6K miles ago..).

1. I disconnected the fuel hose from the fuel rail and nothing came out - no fuel at all.

2. The fuel pump fuse seems intact (near the steering column)

3. In the trunk, I looked at the fuel pump controller pins and they look okay (no burn marks) - bright and shiny - not sooted .

4. The fuel pump resistance is coming b/w 1.9 to 2.5 depending on how stable i keep the ohm meter leads. Does this mean the pump is bad? The manual says 0.5

5. Any easy way to check the fuel pump or the controller for sure? I think I am checking the reisstnce of the pump correctly, not sure how to check the controller.

Thanks

I do have the manual and am trying to go thru it right now.

[DAEDALUS]

Did you check the pump fuse? -Blue one in the middle of the right fuse column. Check the back of the EF/EC section. Voltage values are listed for the pump a various conditions. If the pump is getting the right voltage and it itsn't spinning, something's probably burned out. Very rare...I have to ask--is it a factory pump?

[firstq]

1. Yes the pump is factory pump.2. The fuse appears to be okay

3. The voltages to check are b/w the fuel pump controller (no tthe fuel pump) and the controller harness, right?How do you guys get the pump controller unit out, it is so difficult to get in there to put the alligator clamps in for voltage testing.

How about fuel pump relay?

Thanks

[DAEDALUS]

Sorry, didn't see the point about the fuse being OK...you can check its resistance to be certain.A number of checks you can perform involve the car running, which isn't an option obviously. You might need to have 2 people working on this one to take measurements during the 1st 5 seconds after you turn the key to ON, when the pump pressurizes the fuel rail for startup. You can measure voltage either at the fuel pump controller or at the ECU. Kind of a wash IMO; I'd probably go to the ECU just cause I'm more familiar that way. Check the manual for the pin location...there are a few pages near the back. EF-EC 183 in my manual, and EF-EC 168 for diagnostics. You can try running the pump directly off a power source, but I wouldn't use 12V...maybe 6 or 8V just to see if it turns. Or try measuring the pump voltage from the back of the connector pins right after your helper turns the key.

[firstq]

Donno guys, last night I was so frustrated with this car - Having difficulty getting into the pump controller for pushing the alligator clips for measuring the voltage - I decided to just giggle the connector harness and put it back together - cranked the engine and the car started in no time.

Pehaps the controller or the pump was (fill in the blanks).

I will keep an eye on it to see if it happens again. Will do the fuel pressure test to see if pump is functioning okay - atleast the car is running now. My only concern is that the fuel pump goes out of 12month warranty in about 12 days.

Thanks

[Q451990]

How bad did the old pump get before replacement... how many miles, realy bad hum or just a little? I'd lean toward a controller problem, but it could be the pump I guess. I assume you removed the back "wall" from the trunk to get to the controller? If so, and you're somewhat electrically skilled, I'd pull the controller and take the cover off to look for toasted leads, etc...

It might be something that's temperature sensitive. Since it's warming up in most parts of the country (where are you located?) you might see if you can recreate the problem by heating up the controller with a hair dryer. At least you could narrow it down that way. It's amazing what you can find with the a hair dryer and freeze spray.

Heath

[firstq]

How do you guys get to the controller to get it out?

Do I need to get the back seat out for this?

Heath: The old pump was not dead - the car used to buck here and there but continued running for a week or 2 before I had it replaced around 100K miles. It is now 6K on the new pump.

Thanks

[Q451990]

Taking the back seat out won't do much for you since you'd practically have to destroy the divider between the trunk and cabin (some sort of permanantly attached insulation backed rubber skin) to access anything. Have you taken the access panel out of the back of the trunk to expose the tank?

Heath

[firstq]

Wait a minute - I am talking about the controller not the pump - do I still need to expose the trunk?

The fuel pump controller is located fairly isolated from the trunk bolted to the top frame in the trunk [away from the fuel tank], may be you are right...

[mark thompson]

to remove the fuel pump control unit you have to remove the parcel shelf the two screws are under it to remove the shelf you have to remove the back seat

[Q45tech]

"The old pump was not dead - the car used to buck here and there but continued running for a week or 2 before I had it replaced around 100K miles. It is now 6K on the new pump."

Was the tank [bottom] inspected for dirt and water [rust stains] when the pump was changed........not unusual for this to be ignored.

Examine the interior of the controller looking at every connection with a magnifier...........bet you'll find a solder connection that was overheated by the previous pump......while you waited the few weeks to change it.........and the months the pump was bad before then.

You can examine the pump [motor] current waveform looking for bad commutators /!/!/!.../!/! All the motor pole should draw the same current with no drop outs [unless dirt worn commutators]