Fuel Pump Woes

[alsgro33]

Would any of you fine people be willing to take me through troubleshooting a "crank, no start" condition on my 1981 Zagato w/ the Bosch FI?

Last year, I pulled the tank, had it cleaned and dipped, replaced the pump, filter, and various hoses. I also yanked the injectors, had them professionally refurbished, and replaced the engine side fuel hoses during re-install.

After all that work, the engine ran well. Idled fine, etc.

The problem was that is felt like driving in an empty paint can, so I set about replacing all the motor mounts, shocks all around, front end bushings, etc.

I also pulled the steering rack and had it professionally rebuilt.

OK, so... I wrestled the rack back in and reconnected over the weekend and thought, "I'd better start this thing, just to test whether the rack has any leaks before I button this all up." Mind you the car had been on stands for about 2 months at this point, but the gas in the tank should be ok.

It now cranks and doesn't start, when it was running and starting just fine when I put it on the stands. I've done the "flap" test on the AFM, and I don't hear the pump running. I also pulled the fuel line off to the rail and cranked-- no fuel comes out. So, fuel pump doesn't seem to be working, but it was new and working fine when it was parked...

Anyone have some suggestions on what I should try next? I have a spare "dual relay" for the FI system that I tried, and I'm getting the same result.

Any thoughts on direction greatly appreciated!

[peteracs]

Hi

I am assuming you have a US spec car which many of us will have had no experience of the additional 'enhancements'. That said I would start at the fuel pump with a meter and see if you are getting any power being supplied to rule out a failed pump. Failing that it would be a case of working back to see what is not occurring to provide the power.

You will obviously need the US spec wiring diagram to do this.

As a test you could of course simply run a bypass supply toontje pump to check it.

Sorry not that useful, if you need a copy of the wiring I think I have a copy supplied by Tyson from the US who is very knowledgeable and active on the FB groups.

Peter

[Nigel]

Hi
These may help you.
They are not necessarily US spec but show the euro layout in some detail.
Peter's tips will also assist in tracing the issue.

I can also email to you
if they are not clear enough.

Edit: Sorry about inverted 1st image, I'll fix that tomorrow.

Nigel

[alsgro33]

You all are the best! Thx for the help!

I'm working on getting 12v straight to the pump to check it. Hard to believe it would've died from sitting 2 months, but it seems like that's the most likely culprit at this point.

Quick question: any of you have luck replacing one of these pumps w/o removing the tank? It'd be my 3rd time, and it's such a PITA!

Appreciate you fellas,
Al

[Nigel]

The pump on euro cars is mounted in a bracket above the rear cross member. You certainly don't need to move the tank. Access is not easy, but it's doable.  Undo the bracket from the cross member and drop the whole assembly. Of course,  yours may be different.

Nigel

[alsgro33]

I'll try that, Nigel. Appreciate the tip! From what you said, I think mine is the same setup.

I was able to get a jump box connected right to the pump, and it just clicks. Doesn't sound like it's running.

I guess it's time for a new one. I just checked through my parts order, and I never did order one for this car, so I must've just reused the old one. I'll try a new pump and see where we are. My meter is reading 10v during crank, but it's tough to get the probes in there, so I feel like it's getting power.

Anyway, thanks from California!

[Nigel]

One further thought, US cars may be fitted with an inertia cut-off switch which I don't think are fitted to euro Betas.

[alsgro33]

FYI, a new pump fixed this issue. It died.

But also, one of the wires in the dual relay had come out of its spot in the connector and was pushed into the wrong hole! Good reminder to check and be sure that all the wires are set into holes that actually correspond to one that’s being used by a pin.