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No spark
#21

DME relays can be intermittent. replace



fuel pump check valve is the most likely suspect in the hard to start issue. when it fails, the fuel empties out of the line, but some stays in the fuel rail. it will start and then stall. it will take about 10-15 seconds of cranking to fill the line and start the car.
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94 Midnight Metallic Blue Cab Porsche 968 w/deviating cashmere/black interior and WAY too many mods to list - thanks to eric for creating www.968forums.com



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#22

Forgot to mention that when the car does start and run intermittantley, it runs very, very rough. In fact the last time she ran it didn't smooth out at all and wouldn't even stay running. I read a thread for ds968 who sounded like he had the same problem and was going the rout of fuel delivery issues- filter, check valve etc. I expect I should go this route as well? The irregular idle is not a major concern right now since I can't even get the car running. Thanks.
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#23

back to the basics: verify fuel, spark, compression



with all due respect though, based on the exchange so far, this does not sound like something you should be doing yourself. there are way too many things that could be going on. working through them is very basic for a mechanic, but can be a daunting, confusing, and frustrating task for the amateur.
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94 Midnight Metallic Blue Cab Porsche 968 w/deviating cashmere/black interior and WAY too many mods to list - thanks to eric for creating www.968forums.com



"It isn't nearly as expensive to do it right as it is to do it wrong."
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#24

[quote name='dmdjordan' timestamp='1379529211' post='149569']

Forgot to mention that when the car does start and run intermittantley, it runs very, very rough. In fact the last time she ran it didn't smooth out at all and wouldn't even stay running. I read a thread for ds968 who sounded like he had the same problem and was going the rout of fuel delivery issues- filter, check valve etc. I expect I should go this route as well? The irregular idle is not a major concern right now since I can't even get the car running. Thanks.

[/quote]



That sounds like it could still be the DME relay. Even a hairline crack in the solder will cause issues. I would reinforce the solder joints on those few contacts as mentioned in the link I sent you. In the meantime, pick up another DME relay on Amazon for $14. http://www.amazon.com/URO-Parts-993-615-...0066RMUIG/
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#25

Have you looked at the plugs recently? It's good that they are new but they can be wet or fouled as well as new.



I suggest trying to start the car when it is difficult and then (without it starting) pulling the plugs to see if they are wet and smell like gas. If so, you have a good clue that you have excess fuel. If not, give it a squirt of gas or starting fluid (ideally behind the <acronym title='mass air flow'>MAF</acronym>, there are vacuum hoses you can use.) If it runs for a second you have a clue that you are short on fuel.



You are in basic troubleshooting mode. Check for fuel, too much or too little, check for spark, using a spark checker or other means to make sure your spark can jump a 1cm gap. Check the spark timing. Check for a signal to the injectors (noid light.) Check for a loose distributor rotor. Check the compression if you are still not on to anything.



If it's too much gas this is often a failure of the fuel pressure regulator, either stuck or leaking. It could also be the DME temp sender suggesting you need lots of gas to start a very cold engine. At any rate determine the starting point via basic troubleshooting and let us know how you get on.
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#26

they could be loose too. i had that happen once. now i torque them every time.
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94 Midnight Metallic Blue Cab Porsche 968 w/deviating cashmere/black interior and WAY too many mods to list - thanks to eric for creating www.968forums.com



"It isn't nearly as expensive to do it right as it is to do it wrong."
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#27

[quote name='jfrahm' timestamp='1379681593' post='149655']

Have you looked at the plugs recently? It's good that they are new but they can be wet or fouled as well as new.



I suggest trying to start the car when it is difficult and then (without it starting) pulling the plugs to see if they are wet and smell like gas. If so, you have a good clue that you have excess fuel. If not, give it a squirt of gas or starting fluid (ideally behind the <acronym title='mass air flow'>MAF</acronym>, there are vacuum hoses you can use.) If it runs for a second you have a clue that you are short on fuel.



You are in basic troubleshooting mode. Check for fuel, too much or too little, check for spark, using a spark checker or other means to make sure your spark can jump a 1cm gap. Check the spark timing. Check for a signal to the injectors (noid light.) Check for a loose distributor rotor. Check the compression if you are still not on to anything.



If it's too much gas this is often a failure of the fuel pressure regulator, either stuck or leaking. It could also be the DME temp sender suggesting you need lots of gas to start a very cold engine. At any rate determine the starting point via basic troubleshooting and let us know how you get on.

[/quote]



This is good advice. This should not be hard to troubleshoot to get you going in a direction.



Is jfrahm the same one on quattroworld? I thought your user name looked very familiar.
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#28

Yes, that's me. I have an A8, it's getting somewhat old and battered and I am keeping an eye out for a replacement, although my car still works great so it's low-priority.
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#29

OK guys this is great stuff. I have been looking through the site at posts of similar issues and at the DIY section on fuel pump replacement as this appears to be a possible culprit. I will also review the manual on this section for further guidance. I would take the car to a qualified Porsche mechanic if there were one close to me but that is not the case. I will check with the local PCA members to see if there are any 968/944 specialists among them and seek help there as well. Mean while I shall follow the suggestions given here to try and track things down. My issue right now is time. I travle M to F then need to try and get all my s*** done on the weekend. Anyway, I shall perceiver. Thanks.
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