Mrmerlin

Matt it will just take going through the WSM test procedure to nail down the culprit , possibly a bad switch on the clutch or the brake pedal

AO

Wow! Was off grid this week with kid duty.
Big thanks to Mike for the support.

So with pump running, there is little or no fuel.

I never touched the fuel pump or filter. But two ( make taht three) other things pop into my head as potential things to check.

1. Is there gas?
2. Is there vacuum in the tank (i.e. Vent line blocked?)
3. Bad fuel pressure regulator?

@ drbob

LH has been rebuilt... Should be fine.

Hang in there Steve. You will be rewarded.

Mrmerlin

Here is what i would order,
1 fuel filter
6 sealing washers,
1 hard line from pump to filter
1 check valve
1 fuel pump
NOTE if you order the fuel pump then forget the check valve as it should come with a new valve. why order all of these pieces ??
Because after you have the filter swapped out and you find that the gas is now leaking from the sealing ring ( they always get replaced when doing this job otherwise you have a 80% of a fuel leak)
Why the hard line?
because there is a very hi probability that the hard line on the car is already deformed from someone over tightening the cap nut to try to stop the gas leak because they didnt replace the sealing washers.
I know this may be overkill but after you have replaced a few filters you will realize that in order to be successful all of the associated parts must also be renewed.
There are many that post here that they were going to replace the fuel filter only to find out that no amount of tightening will stop the gas from leaking.

Note tie pieces of cloth around your wrists so gas wont run down your arms. wear gloves,
have a drain pan available.
Have a fire extinguisher handy ,
Disconnect the battery

Mike Frye

Dr. Bob, we left out a few tests we did, but one of them was to check a plug (found it was dry) and check a FI lead (we had voltage triggers). Jumping the fuel pump relay and hearing it but having no fuel at the fuel rail seemed a smoking gun that at least until that situation is resolved we can't get any further.



I didn't even think of this one until I got home last night.
I e-mailed Steve and he said there's a full tank.

Don't know about that. MrMerlin asked Steve to check by pulling the gas cap but I didn't think to check that.
Wouldn't we still have fuel at the front of the rail with the pump relay jumpered though?

Stan,

That's a great idea and thanks. Hopefully Steve checks in and agrees. I'd rather be prepared and not need a few parts than be stuck with a leaking fuel line trying to figure out what to do next.

Steve, what do you say?

Mrmerlin

note you only need 3 sealing washers per attempt,
the other 3 are for spares

James Bailey

I highly doubt that it is a fuel filter......I can not remember how many I sold to people when they requested it only to have them call again asking what to check next ! I have posted before that I NEVER knew of a 928 being fixed by a fuel filter change I think one or two people replied that it "fixed" their 928 once. It might be good to run a direct jumper wire from the battery to the + terminal on the fuel pump under the tank then if it runs check for fuel at the fuel rail.

Mike Frye

Jim,

We heard the fuel pump running when we jumped the FP relay (30 to 87). It was running and sounded normal, but no gas at the rail. Actually there was a very small trickle of gas, but it was more like whatever was laying in the rail was just dribbling out. What would a hot wire to the fuel pump do that jumping the relay wouldn't?

I figure it has to be a completely plugged filter or fuel line somewhere, and the filter is of unknown age anyway so it wouldn't be a wasted effort. When we've got the filter, we can get up under there and check for fuel pumping at the filter as well.

86'928S MeteorGrey

Does this year have the in tank pump? What about that little rubber hose that deteriorates and clogs up the in tank pump? Could it be a clogged internal pump and a running external pump?

https://rennlist.com/forums/928-foru...ight=tank+pump

Mike Frye

Mike,

It looks like the dual pumps are 89+ according to that link.

I'm definitely leaning toward a bad pump at this point based one what everyone is saying. We'll probably end up doing it in two steps. Yesterday we determined that we've got spark and everything else looks good but we've got no fuel.

Now once we find out why there's no fuel we'll be on the way to a solution and some nice reliable driving for Steve.

Hilton

Mike - are you completely sure it sounded normal? I ask as a friends 83 had a jammed pump, and on the first listen, I could hear a faint pump noise, so assumed the problem was elsewhere. The noise turned out to be the motor vibrating, but not spinning.

Using a hot wire direct from a battery will give you a good voltage feed and current support for the pump - its possible a corroded connection or ground issue is giving too low a voltage to be useful.

86'928S MeteorGrey

Ahhhh. I knew that! Just in case someone upgraded an '89 tank and pump, I'll take credit for the solution now.

Otherwise, i'll just say "DOH!" and move on..

Mike Frye

Actually no, not sure. It didn't sound like it was straining, but maybe once we get the filter cover off I'll have a better listen.

My plan is to drop the old filter out and jump the FP relay again to see if it pumps out with the filter off of there and the line open. If we still get nothing we have to look further, if it pumps then we'll try the new filter.

James Bailey

The wire basket screen on the screw in filter can break loose and move around in the bottom of the gas tank and if it turns 180 degrees the flat solid round end can get sucked up against the outlet pipe and shut of the flow. I like jumping the pump with power because it is obvious and bypasses a number of other potentials plus by removing the cover below the tank you really can hear the pump.

Mrmerlin

if you do get fuel from the pump then is there any chance that one of the hard lines may have gotten pinched shut?
from bad jacking or road debris

Droplink

If it doesn't pump well, try reversing the leads and run it backwards. This can sometimes dislodge an obstruction and get it flowing properly again.