Hi all,

I have a 95 960 (3ltr) and it has stalled on me and fails to start again.
I have tested for spark and didnt get any, though I am getting injector pulse and fuel pressure.

I put a test light to the cable going into one of the coil packs and got a signal only as I stopped winding (beats me what that means).

Basically I was driving, the revs became really erratic and that was that!
All the wiring looks to be ok and I am lost where to go from here besides a new ECU, but thats an expensive guess! Any thoughts would be really appreciated!

Thanks!

 

There is a ignition test lead at the back of the head with the cam sensor and rpm sensor. It is a female white and red lead I believe, that and ground should show 12 volts with ignition on.

Rpm sensor would knock out spark, could just be oxidation on the connector.

There is also an ignition relay that could have have oxidation.

DanR '94 964 386,000 miles (152,000 on the new engine)

 

Thanks for the reply.
I hooked up a test light to the Ignition test lead and am getting odd behaviour!
When I turn the ignition on, I get momentary power and then it is gone!
I tested the ignition relay and it is not getting power to switch it.
So what is in between the ignition switch and the ignition relay?
I have read that Power modules can go, but that would be after the relay?

 

Not sure whether it is worth mentioning... but pulling and reinserting the fuel relay causes the same behaviour in the switching of the ignition relay :/

 

I am thinking that the power stages are after the relay too. Don't have my manual with me at the moment. But it does sound like you might have a faulty ignition switch. Does the drive have a heavy key chain that dangles? Have heard that puts vibration and stress into the switch and can cause failure.

Remind me, does the engine turn over or is it like a dead batter and it will not crank? Is the battery good, are the cables clean. Does it help to jiggle the gear selector?

DanR

Dan

 

Thanks for the reply Dan! Turned out to be a bad earth wire connection under the inlet manifold!
So it started finally, but funnily enough, the problem doesnt end there!
The thing will not idle. Very unresponsive to throttle. I have tested the TPS and it seems to be good. Really tiring this car!
Any thoughts would be greatly appreciated

 

Try this. Turn off engine, disconnect the MAF, the plug in the air ducting just after the air filter box.

Try starting engine, it may stumble for a few seconds, but if it evens out and runs smoother, then, the MAF is suspect or the wiring to it. Most sensors on these engines are very durable, but they all can go crazy with resistance in the connectors. So a cleaning and tightening of the electrical connectors in annual maintenence on my volvo.

The engine will run and make it home with out signals from the following sensors, MAF, temp and cams sensors. It does require input from the RPM and throttle position to run correctly. So disconnecting those first three one at a time might help in diagnosis. The thing is you do not want to run for very long, like several hundred miles as fuel mileage and runnablility suffers greatly.

I would look for air leakage in the air intake ducting. You might have to loosen the coil packs at the top and remove one coil at a time while engine is running to see if you can locate a cylinder with a miss. It will be the one that does not change the idle of the engine upon removal. If it just one cylinder with a miss, the idle will not alter when the suspect coil is removed.

Good luck,

DanR

 

Thanks for the replies Dan. Turned out the earth under the intake manifold was loose. The car started after fixing this problem, though it ran like crap. Spent another bunch of hours on the car to find out the MAF was also playing up. Disconnecting it is the fix for the moment.

Thanks again