Stylemobile

I am relatively new to Porsche 928 ownership. I purchased two of them last year.

This original 1984 928 has been sitting in my driveway since i drove and parked it there 6 months ago. It ran strong at the time. I want to get it on the road again. I may sell it or keep it as the 'Guest Porsche'. : ) It needs an interior and a paint job as well as some exterior trim parts.

Anyway,
I put a brand new and fully charged battery into it a few days ago.

I put 3.5 gallons of fresh gas in the very low or near empty gas tank.

The starter cranked fast with the ignition key but the engine would not give a single hint at wanting to fire.... not a fart.

I pulled a spark plug and grounded it to the chassis and had someone crank the starter- full spark.

I sprayed starting fluid in the air intake while cranking and the car fired up and ran several seconds. This was repeated a few times.

I pulled a gas line off where it 'T's near dead center at the top front of the engine at a unit with a vacuum line under the device (part #OEM-92811020200 diaphragm damper?) and cranked. No fuel.

I swapped out the fuel pump relays and the alarm relays with my other 928. The running 928 still functions-the sitting one still has the same non-starting issue.

I cleaned and checked fuse #16. Nothing.

Do you have any advice on how to proceed with a fuel delivery issue with the parameters stated above? It ran when i parked it. OH, I DID charge the battery with a 6 amp charger several months ago with the terminals still attached. (Pre-'disconnect the battery always' knowledge days.) Could I have damaged something?


Sincerely,

Allen Howells/ Allentown, PA

StratfordShark

Have you checked whether the fuel pump is running when powered up?

Mike Frye

How cool is that?

+1 on the fuel pump, you should be able to hear it while you're cranking. Do a search on here, there's a write-up on 'jumper' for the fuel relay so you can see if you hear the pump running. (It doesn't run unless the engine is cranking under normal circumstances, and it might be hard to hear it while that's happening). This will also isolate whether or not it's the relay.

You can get a fuel rail pressure gauge for under $50 I think, it will help with diagnosis as well as setting a baseline so you know if there's a problem in the future.

Dennis Wilson

It's also a good idea to change out the fuel filter if it has sat too long without stabilizer in the system.

Dennis

Stylemobile

Latest efforts:

Relay checks out OK. I removed the cover of the relay and watched the contacts pull in upon ignition starter engaging.

Ran wire conductors directly from the battery to the fuel pump. No noise from the pump at all. Must the fuel pump be replaced? Why would it just cease to function? Is there some 'prodding' i can do to it or is it basically a disposable unit ? These suckers are expensive. I am trying to get this car out to sell and hate to sink almost $300 for a freegin fuel pump. Suggestions?

Dennis Wilson

Try reversing the voltage on the contacts. If the pump is locked up due to crud from the tank it may loosen it. Also, have you changed the filter?

Dennis

Dennis Wilson

Forgot to mention that the smaller connection on the pump is positive. Also, have you checked the ground wire for a good clean connection?

Dennis

Stylemobile

Applied voltage directly to the fuel pump and tapped on it with an old railroad spike lying nearby. Started whirring so I turned the key and she fired right up! Left it run for an hour or so and have had another dozen successful starts.

Thanks for all the tips and guidance.

Allen in Allentown, PA