QuestionI have 1981 928. Keep it garaged in North Carolina. I disconnect the battery, but it sits for long periods of time. We live in Florida. So it doesn't get driven. Now I can't get it started. First Time it has failed to respond.
It wants to start, but doesn't. Is it fuel? Is it a stuck valve? Is it EGR valve? Is it OXS sensor? I'm in the mountains and tough to get the car on a tow truck, so getting it started will allow me to get it to a proper mechanic for a check-up. Any ideas?
AnswerGeorge,
Hi. A bit unlucky with the 928? Anyone with a 928 is very lucky indeed!
The laundry list of possible non-start causes is quite long. I'll put them in order of the most likely, because of the car sitting idle. And I'll assume that what's happening is the engine will rotate fine, but it won't start...right?
Most likely:
1. Crap, gunk, crud and other dried gasoline residue where it shouldn't be.
Also likely:
2. Fuel tank empty.
3. Not a fully charged battery
4. Battery terminal connections loose or corroded.
5. Fuel not reaching the injectors
6. Ignition components damp or damaged
7. Worn plugs or faulty gap on plugs
8. Loose wiring in the starting circuit.
9. Broken loose or disconnected wiring at the ignition coil or faulty coil.
Obviously, the chance of crud being in the fuel lines, especially the injectors themselves is very high...unless, when you stopped driving the car last it ran out of fuel when you parked it.
I don't have any easy answer...and I wouldn't want a pro to use his/her $100/hr expertise searching for gunk.
Here's what I'd do:
Outside, or in a hugely ventilated and spark free garage:
1. Prove that the items 2-9 can't be at fault.
2. Drain all the old fuel and replace it. Replace the fuel filter with a clear one I could see thru for this testing.
3. Prove the fuel pump is gushing clean gas at the junction of the fuel lines just before the fuel gets to the fuel injectors.
4. Remove each fuel injector in turn and reattach the wiring so you can observe the fuel spray as the engine cranks over. (Better go get another spare battery... and maybe a starter). Observe the spray and if it appears faulty compared to the others, clean the injector.
5. If all the fuel injectors actually appear to be working cleanly, there may be one other culprit. Many fuel injected cars (I assume the 928 too, but I'm not sure) have cold start valves, which inject an extra bit of fuel into the manifold to aid cold starting. Clearly, if you have one, it could be gunky too. I wish I could point you to it, but I can't with me sitting here in California.
6. Lastly, depending on the timing of the last "tune-up". I'd make darn sure everything tune-up wise I could replace would be replaced...all the plugs, the filters and all the electrical components I could afford to make new.
7. When I prove the fuel gunk is no longer a possiblity, I'd recheck all the electrical connections and grounds in the starting and coil circuits...not by merely wiggling the wires, but by disconnecting the wires, cleaning the terminals and mounting points and then re-atteching them.
8. If all else fails, hip the dang thing far, far away....maybe just send it to someone anonymous...maybe select who its sent to randomly...say the last person who happened to communicate with you over the internet. My address is...
9. After you've either started the beast or completed all the steps, write back to me using the follow-up feature of All-experts...I need to know how this tale ends...or maybe I can come up with another plan...or maybe I can give you my ship-to address...Look forward to your success story.
Dave
