Intermittent starting : 944 2.7NA
06-03-2004 | 08:11 PM
#1
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Intermittent starting : 944 2.7NA
Hi folks,
I'm a newbie to this list, and a new owner of a white Euro Porsche 944, 1989, 2.7 litre non-turbo, and it has an intermittent starting problem. It cranks over just fine. Sometimes it starts in half a second. Sometimes it doesn't start in 15 seconds. Sometimes it doesn't start after several attempts, and I have to open the bonnet. Yawn.
When I fiddle with the DME and XX relay, it will often start. Always starts, in fact, sooner or later. But one day, it may not.
Having seen some posts, maybe I've been lucky, and my prob is waiting to trip me up while doing a ton down the motorway.
I took the DME relay off and inspected for bad solder joints, they all look perfect, clean bright, good meniscus, etc. The contacts are clean and bright. I've tested the relay off the car, I can't get it to fail, and it has good low contact resistance when operated.
Any idea where I can get a schematic of the ignition circuit and DME connections? Should I be looking for spark next? Or poor contact between the DME and relay socket?
The car has a COBRA immobiliser fitted. Anyone know how this achieves it's immobilisation.. ?! Cos I'm starting to wonder if whatever it immobillises is not always un-immobilising, even though the tell tale LED says it's OK to go.
Cheers
Russell
I'm a newbie to this list, and a new owner of a white Euro Porsche 944, 1989, 2.7 litre non-turbo, and it has an intermittent starting problem. It cranks over just fine. Sometimes it starts in half a second. Sometimes it doesn't start in 15 seconds. Sometimes it doesn't start after several attempts, and I have to open the bonnet. Yawn.
When I fiddle with the DME and XX relay, it will often start. Always starts, in fact, sooner or later. But one day, it may not.
Having seen some posts, maybe I've been lucky, and my prob is waiting to trip me up while doing a ton down the motorway.I took the DME relay off and inspected for bad solder joints, they all look perfect, clean bright, good meniscus, etc. The contacts are clean and bright. I've tested the relay off the car, I can't get it to fail, and it has good low contact resistance when operated.
Any idea where I can get a schematic of the ignition circuit and DME connections? Should I be looking for spark next? Or poor contact between the DME and relay socket?
The car has a COBRA immobiliser fitted. Anyone know how this achieves it's immobilisation.. ?! Cos I'm starting to wonder if whatever it immobillises is not always un-immobilising, even though the tell tale LED says it's OK to go.
Cheers
Russell
06-04-2004 | 12:43 AM
#3
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From: A Quiet Little Lake In The Middle of Nowhere
I want to say that I've heard others talk abou this problem and that it could be a sign that your fuel pump is going out. I had a similar problem with the '86 during the 2 years that I had it. I just let is sit for a minute or 2 and she fired right up. Wasn't that annoying to do anything about it.
Cory
Cory
06-04-2004 | 01:00 AM
#4
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From: Burlington ky
i have an 89 w/ the same problem, next time it happens, wiggle the two wires w/ the plugs right over the rear of the engine going to the reference sensors, ill bet that is it. That is what i found, and it works every time.
06-04-2004 | 10:01 AM
#5
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Thanks.
I'll see if there are some pictures of the sensor wires somewhere: at least it will give me something else to wiggle.
How about the circuit diagram info: can someone point me to an online diagram of the DME and fuel/ignition circuits?
cheers
Russell
I'll see if there are some pictures of the sensor wires somewhere: at least it will give me something else to wiggle.
How about the circuit diagram info: can someone point me to an online diagram of the DME and fuel/ignition circuits?
cheers
Russell
