S2 no-start: plug ID and diagnose?
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Starter is turning, but the engine won't fire. Sorry there isn't a pic. Right behind (and a little to the passenger side) of the cam drive gear/rotor housing. It's got three leads, and branches off of the same cable bundle that goes to the AFM plug. My plug (male end) was badly repaired by a PO, and fell apart on me, so I have just the bare leads plugged into their respective females. Haven't come up with a good idea for repairing the plug. I'm assuming this plug is my starting problem because (see list below) and because I've had an intermittent hesitation problem that greasing these leads seems to have had an effect on. Should I be checking continuity between these three leads and something else, or possibly the voltage I should see at the three leads while trying to crank the car?
Before you ask: previously done
fuel filter repl, injectors rebuilt
DMER repl
fuel damper and reg repl
almost every plug I can get to di-greased
grounds cleaned and greased pretty recently
and I'm sure more stuff that I can't remember
- FWIW I'm a recent and future member. Thanks loads.
Before you ask: previously done
fuel filter repl, injectors rebuilt
DMER repl
fuel damper and reg repl
almost every plug I can get to di-greased
grounds cleaned and greased pretty recently
and I'm sure more stuff that I can't remember
- FWIW I'm a recent and future member. Thanks loads.
Last edited by Brett944Cab2; 03-19-2004 at 11:14 AM.
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Sounds like the O2 sensor plug. The stock ones are an amber colored plastic and seem to fall apart from the engine heat in a few years.
I would trace the wires and check. If so just solder them. Put a piece of shrink tubing over them before you do.
I would trace the wires and check. If so just solder them. Put a piece of shrink tubing over them before you do.
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That is the hall effect sensor for the DME. It tells the dme when cyl 1 is at tdc.
That would not stop the engine from starting.
Look at the little thing by the driver's side headlight. That's the ignition module. It could be bad, replace it. Before you do, check the simple stuff... Is the DME relay new or good? This would cause hard starting/stalling/no start. That's more likely than the ignition module.
Dal.
That would not stop the engine from starting.
Look at the little thing by the driver's side headlight. That's the ignition module. It could be bad, replace it. Before you do, check the simple stuff... Is the DME relay new or good? This would cause hard starting/stalling/no start. That's more likely than the ignition module.
Dal.
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Thanks for a reminder on the ignition module - forgot that one, and it's not something I've already done. See my list above for stuff I have done - DME Relay among them. Other ideas?
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Did you check the dme itself?
Make sure that the DME is dry and tight - the battery box can rust out and drench/ruin the DME.
Could also be cracked solder joints in the DME. open it up and get a magnifying glass and check it out.
Before you do that, give the DME a good thump with your fist and see if it starts.
Other than that, I'd guess the ignition module.
You can get a new plug end for the hall effect sensor from porsche and replace it.
Dal.
Make sure that the DME is dry and tight - the battery box can rust out and drench/ruin the DME.
Could also be cracked solder joints in the DME. open it up and get a magnifying glass and check it out.
Before you do that, give the DME a good thump with your fist and see if it starts.
Other than that, I'd guess the ignition module.
You can get a new plug end for the hall effect sensor from porsche and replace it.
Dal.
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I had the exact same problem on my S. It caused real hard starting and bad hesitation. The car would start after about 5 mins of trying. My understanding was if the DME does not get this signal it cuts timming back.
I just cut off the plug from the sender and sodered the wires together. I'm not sure of the color combos. I can go look if you need.
I just cut off the plug from the sender and sodered the wires together. I'm not sure of the color combos. I can go look if you need.
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Thanks for the help. We had some hard rains early last week and the P-car took a little while to dry out. Running just fine now. My grad-student salary isn't supporting a garage, and yes, I do need to use my cover more faithfully.