No start... getting worse...
11-22-2006, 06:51 AM
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No start... getting worse...
1984 Carrera
My little starting problem has progressed from refusing (arbitrarily) to hot-start to not starting at all. I can hear the soleniod click when the iginition is turned but the car won't fire. All electrics are working. It tried turning the first time (very briefly) then failed to start. Push starting doesn't work either.
Oddly, the imobiliser decided to play up too - it would beep and flash the hazards but not lock the doors (with the fob).
Any ideas? The battery is fine but I've yet to checking the grounding and a few other items. I don't have a lift or any way to get under the car to check the starter/solenoid.
Help?
Thanks
My little starting problem has progressed from refusing (arbitrarily) to hot-start to not starting at all. I can hear the soleniod click when the iginition is turned but the car won't fire. All electrics are working. It tried turning the first time (very briefly) then failed to start. Push starting doesn't work either.
Oddly, the imobiliser decided to play up too - it would beep and flash the hazards but not lock the doors (with the fob).
Any ideas? The battery is fine but I've yet to checking the grounding and a few other items. I don't have a lift or any way to get under the car to check the starter/solenoid.
Help?
Thanks
11-22-2006, 02:25 PM
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Check ground connections by battery and have the battery tested as well. If you have a broken cell then the battery may appear ok, but when loaded it dies. Next I'd check the DME relay. You'll find that one under the driver seat. Always have a spare.
Michael
Michael
11-22-2006, 04:47 PM
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Yea I would say Michael is dead on I have had this problem before. Buy some starting fluid and just spray a tiny quick puff into the intake snorkle. If it starts up right away no problem (and possibly dies a little later) it could be one of two things 1. Fuel Pump or 2. DME Relay. I went straight for DME relay becuase I knew my fuel pump was fine and my overcharging alternator had fried my DME. I had gotten a new DME and alternator. Usually the DME relay blows first. If your fuel pump is fine I am sorry to say you may have bigger problems, overcharging alternator. Get a voltmeter and check the battery to see if youre getting more than 14 volts pumped to the battery. If you need any help let me know.
Oshin
Oshin
11-23-2006, 05:01 AM
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Originally Posted by Oshin11
Yea I would say Michael is dead on I have had this problem before. Buy some starting fluid and just spray a tiny quick puff into the intake snorkle. If it starts up right away no problem (and possibly dies a little later) it could be one of two things 1. Fuel Pump or 2. DME Relay. I went straight for DME relay becuase I knew my fuel pump was fine and my overcharging alternator had fried my DME. I had gotten a new DME and alternator. Usually the DME relay blows first. If your fuel pump is fine I am sorry to say you may have bigger problems, overcharging alternator. Get a voltmeter and check the battery to see if youre getting more than 14 volts pumped to the battery. If you need any help let me know.
Oshin
Oshin
11-23-2006, 05:43 AM
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Originally Posted by mflinkenberg
Hey thanks for that - I'll try those things. I'm not sure the 84 carrera has a DME though?
Your symptoms are indicative of a failed DME/Fuel pump relay or a failed immobiliser which takes out the DME/Fuel pump relay by removing the power to the fuel pump relay (there are two relays inside the assembly).
I have seen both relay failures and the UK only installed alarm systems cause this problem.
The cheapest one to look at first is the relay. If the fuel pump is not running no amount of anything will get it started and clearly your fuel pump is not running.
Ciao,
Adrian.
Last edited by Adrian; 11-23-2006 at 01:43 PM.
11-23-2006, 06:42 AM
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Originally Posted by Adrian
Yes it does. The Carrera 3.2 was the first of the series production 911s with Motronic.
Your symptoms are indicative of a failed DME/Fuel pump relay or a failed immobiliser which takes out the DME/Fuel pump relay by removing the power to the fuel pump relay (there are two relays inside the assembly).
I have seen both relay failures and the UK only installed alarm systems cause this problem.
The cheapest one to look at first is the relay. If the fuel pump is not running not amount of anything will get it started and clearly your fuel pump is not running.
Ciao,
Adrian.
Your symptoms are indicative of a failed DME/Fuel pump relay or a failed immobiliser which takes out the DME/Fuel pump relay by removing the power to the fuel pump relay (there are two relays inside the assembly).
I have seen both relay failures and the UK only installed alarm systems cause this problem.
The cheapest one to look at first is the relay. If the fuel pump is not running not amount of anything will get it started and clearly your fuel pump is not running.
Ciao,
Adrian.
