Runs a few seconds, then Finis!


#1

I have an '84 Peugeot 505 that has been behaving very weirdly.



OK, have you finished laughing? Done with the French car jokes?



OK, here goes. Last fall, the car started cutting out after a while. It would warm up quickly (5 minutes max), run about twenty minutes, then stall and would not restart. It didn’t matter if the car was rolling, or idling in place: it would simply stop running.



Then it stopped running at all. Not having time to mess with it then (and more importantly, not having a garage to work in, and it was winter), I left it alone.



Yesterday I finally got around to trying to fix it. On a lark, I charged the battery and cranked it. It caught instantly! Ran about ten seconds, then stopped. It would not restart.



The fuel pump hums loudly, and seems to put out plenty of pressure, so I don’t think that’s it. But I don’t know what is. Any ideas?


#2

You’ll want to verify that you’re getting good fuel pressure with a testing gauge…simply listening to the pump run won’t help if there’s a blockage in the line, or if the fuel filter is clogged.


#3

Good poing, but when I loosened the connection of the main fuel line to the fuel injector pump, fuel sprayed all over, so it appears it’s getting good pressure. I suppose it could be the injector pump, though.


#4

Next thing to check is if you are getting spark or not when it doesn’t run. Check either with a timing light, spark plug, or tester. One of the two is missing so first gotta figure out which one.


#5

This is Fuel injected I gather, Y/N?. If Y, what sort of FI, Bosch, or some other, ie DELCO?.

And it it mechanical or EFI. 84 is a long time back, so it could be a steam operated FI system.
Bosch CSI was common in the US at that time. but the old 79 beatle had EFI… which was very unpredictable.

Any links to photos of this engien and FI system?.
also, does it idle but stop if you hit the gas pedal or simply start and immediately stop, nothing else pressed or bumped.

Does it have Bosch Electronic Ignition or else?
does it have a distributor, Vac advance? Electronig advance, etc.

I’m familiar with the Bosch systems of that time. But not sure if that is what you may have.


#6

Fuel Injection systems are designed to run at higher pressures so, as described, the fuel pump could put out 30psi and still not be working correctly.

I would check the air intake system, but, first I would do a really simple check.

Get a can of ether starting fluid. When the car won’t start spray a little ether into the air intake and crank it over. If the car tries to start the problem is probably fuel. If the car does not try to start then problem is electrical or air.

Many intake systems have electronic control systems that fail if the air intake has a crack in it or is not correctly assembled. The leaks cause problems with the air fuel ratio sensors if the vehicle is so equipped.

Another culprit could be ignition timing if it is computer controlled, or even if it isn’t. I used to have a motorcycle with a mechanical advance that would get stuck in the advanced position sometimes. It would start and then it wouldn’t idle and if it died it wouldn’t start until it did and then the problem would happen again. I rebuilt the points and replaced the springs. If you have a bad Engine Control Module (ECU, ECM, PCM, etc) or a bad connection to the ECM the spark timing could be screwed up … sometimes.


#7

I checked the old-fashioned way (does it work?) of pulling a lead and placing it near a ground. No spark, not at the plugs, not to the distributor. I guess that makes the suspects the coil, and the electronic control module. How does one check the coil? It is the boxlike type, not the cylindrical type, if that matters.