Intermittent Start Problem - No Taco Needle Bounce

ZZ8388 · **Posted:** Fri May 31, 2013 4:46 am

This is starting to drive me crazy, and is seriously stopping me from driving my 1987 2.5 944.
Intermittently, and with no repeatable pattern, I experience a non start issue.
To date, we have replaced both Crank Position Sensors,
DME relay
Ignition Switch
Lindsey Racing CRANKSHAFT POSITION SENSOR HARNESS FOR 944

Cold start is not an issue. The issue presents after I have used the car, and return to it the same day. Time varies between 30 minutes and 8 hours.
Most recently last weekend, I took my daughter shopping. Drove 5k from home to shops, returned to the car after 20 minutes, and it wouldn't start. Attempted to start the car 4 -5 times, turns over, but no taco bounce. So we went to a cafe for 30 minutes, returned to the car, and it started first time.
There have been other occasions, when returning the car within a couple of hours time frame, and it still wouldn't start. Leave it over night and it starts fine. Which is an issue, if it has been left in a dodgy location overnight.

Anyone got a solution based on similar experience?

tr7v8 · **Posted:** Fri May 31, 2013 7:38 am

The issue n mine when I went through this was a bad connector on one of the crank sensors, cleaned the connections & it was OK, but yours should be OK they are all new. I would start thinking in terms of either a dodgy DME or possibly a loss of feed of 12V or earth to the DME. Does it have an alarm or immobiliser?

944 Man · **Posted:** Fri May 31, 2013 11:51 am

Might it be a poor connector block at the rear of the cylinder head?

jmgarage · **Posted:** Fri May 31, 2013 7:20 pm

Any alarm or immobilisers fitted? even a factory one?

ZZ8388 · **Posted:** Sat Jun 01, 2013 10:57 pm

The car was fitted with the factory alarm, this has been removed by a previous owner.

ZZ8388 · **Posted:** Sun Jun 02, 2013 11:43 pm

tr7v8 wrote:

The issue n mine when I went through this was a bad connector on one of the crank sensors, cleaned the connections & it was OK, but yours should be OK they are all new. I would start thinking in terms of either a dodgy DME or possibly a loss of feed of 12V or earth to the DME. Does it have an alarm or immobiliser?

The car was fitted with the factory alarm, this has been removed by a previous owner.

ZZ8388 · **Posted:** Mon Jun 03, 2013 8:19 pm

jmgarage wrote:

Any alarm or immobilisers fitted? even a factory one?

The car was fitted with the factory alarm, this has been removed by a previous owner.

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Intermittent Start Problem - No Taco Needle Bounce

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