vanster

Just bummed...spent the last 3 days trying to get my 86.5 to run
Rebuilt LH. rebuilt MAV, Witch Hunter cleaned the injectors
New injector connectors, new fuel pump and filter, new relays

Still won't fire. Fuel does not want to fill up the rails and I can't hear the pump working. Any clues?

michaelathome

Not sure on an 86 but:

Alarm?
2 fuel pumps? (inside tank and external)
Regulators or dampeners? (normally they fail open)

Looks like you have done a lot of work to that engine, is the harness ground and plug connected?

You asked for ideas those would be mine.

Michael

SMTCapeCod

Its a beautiful car and was a courageous purchase. I say we'll save it. No nasty noises yet, no need to worry but understand your frustration.

I think the alarm is a good suggestion- I can't say that I know whether that would intercept power to the pump or just the coils/igntion.
Edit: https://rennlist.com/forums/928-foru...f-problem.html

You say it isn't filling the rails, have you left the bleeder cap cracked open on the pass side rail to see whether that's the case?

If you can't hear the fuel pump at the back....then it is unlikely that it is working.
Have you checked for power to the pump? As is, and with a jump wire in place of the relay (search for applicable threads).

SMTCapeCod

Also see here: CPS queues the LH to power fuel pump
https://rennlist.com/forums/928-foru...pump-fuse.html

and,
https://rennlist.com/forums/928-foru...l#post12553327

Cosmo Kramer

What happens when you jump the fuel pump relay? Anything?

JHowell37

+1 on checking the alarm. Where did you get your rebuilt LH?

OTR18WHEELER

The pic shows that the air filter is installed upside down.
I don't know your history with this car, but the fundamentals would be to check the fuel, spark, relays and fuses.
Don't get crazy about too much at once.

hwyengr

Have you tried cutting the tach wire?

vanster

I always thought the arrows on the air filter should be pointing up. Am I wrong?

Cut the tach wire?

It feels like it's going to start with the fuel pump jumped but this is as close as it wants to go
I have noticed a yellow wire behind the ignition switch that has been cut and jumped. I'm suspect of an after market alarm problem
Whatever is happening it does not want to acknowledge the fuel pump, so I am starting to think more and more that it maybe a problem with the once after market alarm. But how to chase it?

OTR18WHEELER

Arrows depict air flow direction.
The 928 air filter has a flat side, and a triangular side, the flat side is down, the top side is tapered to catch air flow from the tube inlets.

OTR18WHEELER

"Cut tach wire" was to see if you were playing along.
There is no tach "wire".

OTR18WHEELER

..cut yellow wire....jumpered?
You may be on to something there.
Can you trace the jumpered wires?
Pics will help.

OTR18WHEELER

BTW, you only have 1 fuel pump.
Another side note...
On these cars, when the "X" relay is mentioned, it is not referring to the Roman numeral "10" relay. The "X" relay, IIRC is an ignition relay.

bureau13

Actually, be careful with those air filter arrows. It seems sometimes they point up, and sometimes they point down...someone posted a picture of two, side by side, with opposite arrow directions. Mine was upside down when I got it too. Just remember hump to the sky...

Bill Ball

When I was helping Van a few weeks back, we had spark, so it's not the CPS. What I observed is that fuel pump did not run. It ran when we jumpered the fuel pump relay socket, but the injectors did not fire (noid light). Now, injectors not firing can be a short in the harness, but because the fuel pump did not run unless jumpered, I suspected the LH. If the fuel pump still does not run, we have to look elsewhere. Van, we need to jump the alarm box 15->87. I don't recall if the alarm knocks out the fuel pump and injectors but leaves spark enabled, but If so, that's next. It should be behind the glovebox....hmmm...wait, didn't we do that already?