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Help...I've got a WIERD "cutting out" problem

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Old 01-19-2005, 01:23 AM
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ARKYTX911
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Unhappy Help...I've got a WIERD "cutting out" problem

Well, when it rains it poors. As you may have read, some numbskull ran into my car at work whilst it was parked 2 days ago. However, since having my 85.5 NA back from getting a new clutch in over Christmas, I've had a problem 3 or 4 times where upon accelerating (2 or 3 times in 1st gear, and once in 2nd gear) that the car just cuts off VIOLENTLY by bucking. If I put my clutch pedal in, then I can keep it from stalling. Back 4 or 5 months ago, I noticed for 1 week a slight tendency to want to cut out at the stoplight when waiting for Orlando's nightmare traffic lights to turn green but nothing this violent.

My question is...what the heck is going on? Is the timing belt messed up (it's was retensioned about 10K ago) or have they screwed something up when they put my new clutch in? All bearings were replaced, save the pilot bearing which was reportedly in good shape ((. The car has 58K on it. After shelling out the kind of $$ for a clutch, I shudder (no pun intended) on having to spend more money on the car this month. I'm starting to wonder why I bought this thing.

Thanks in advance,

ArkyTx911
Old 01-19-2005, 03:01 AM
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KuHL 951
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It's a long shot but after a recent clutch job on my 83 a similarproblem would pop up. Turned out to be damaged rubber connector for the reference sensor that crack easily. My son had broken the rubber part of the connector and the pins were making poor contact. I used several ty-wraps to keep the connectors tight until I rewired new plugs. Hasn't done it since.
Old 01-19-2005, 08:54 AM
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timo944
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This is almost certainly electrical. Check the reference sensors, but it could be a loose fuel pump relay or something too (caused by the impact?). If you play with the ref sensor wires (they connect to the harness behind the fuel rail) or the relays while the car is idling you may get it to act up. Same goes for all of the other connectors in the car.

The other suspect is the fuel pump - it's back there where you got hit.
Old 01-19-2005, 09:51 AM
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Let me add to the "check the reference sensors connections" crowd. SOunds exactly like what happened to me with my '84 a while back.

Regards,
Old 01-19-2005, 12:06 PM
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ARKYTX911
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Hmm, so, how hard is this to check the reference sensor connection? What happens if they're messed up? I had a bad feeling, just didn't mention it, that this COULD be a problem. Maybe I'm not as dumb as I thought.

Thanks again for your help.
Old 01-19-2005, 12:10 PM
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Whats happening is one of the hot conductors is shorting out temporarily(probably due to vibration under load) against the bracket or some other metal thats grounded, which acts a s a switch that kills the car.

If you want to temporarily fix it, assuming thats the problem, just tape the ref sensor leads (particularly around the connectors to the wiring harness near the intake manifold) up with electrical tape and see if the problem goes away.

Regards,
Old 01-19-2005, 12:48 PM
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That metal mounting bracket that holds both sensor connectors can easily ground out to any exposed pin. If your rubber connector housings are really torn up or cracked I would not use the metal bracket at all until you have replaced or shielded the wiring.

Old 01-19-2005, 05:23 PM
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ARKYTX911
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Folks, I'm most gracious for the help thus far. I'll go home tonight and pop the hood open and go in for the investigation. Sounds VERY plausible that this is the problem. Also many thanks for the pic - truly worth a thousand words.

Thanks again,
Ben



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