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No spark. Ideas why not?
#21

This page might be better:



http://968.2ward.com/968FaultCodes.htm



I just tried it again to refresh my memory. the '!' light does not flash, just the CEL. You get one flash from the DME, then the 1 or 2 for constant (1) or intermittent (2) and then the code itself. I got "1 - 5" for no fault. It cycles over and over. If there are multiple issues you should get multiple fault sequences but I do not know if the DME "1" repeats or if you get

1 - DME

1 2 1 (constant <acronym title='mass air flow'>MAF</acronym> fault)

2 1 7 (intermittent oil temp sensor)



Or if you get



1 1 2 1

1 2 1 7



I guess I could disconnect a couple things and see.



Also the tach usually bounces a little when the car is cranking, if the DME is seeing the crank turn.



-Joel.
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#22

Thanks, Joel, your posts are very helpful. Makes sense now. Unfortunately, when I tried it, the check engine light never started blinking, no matter how long I kept my foot on the accelerator pedal. Looks like my DME either isn't engaged...
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#23

Did the CEL ever work? Maybe it was disabled at some point. You can also check the alarm disabler signal, which I think can be found on pin 7 of the 14 pin firewall connector in the passenger footwell or maybe can be located via the notes from clark's bypass instructions.
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#24

Hall sender ?
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#25

Joel,



Yes, the CEL did work back when the car ran. My memory was faulty in thinking it was the "!" that flashed. When I turn the key to the start position, the CEL comes on. But when I depress the throttle, no matter how long I hold it to the floor, the CEL never starts blinking. So I checked the voltage going into the DME by disconnecting the DME's harness, and checking the voltage between the 18 and 24 pins on the connector with the key in the start position. I get +12V (positive lead of my VOM on pin 18, negative lead on pin 24). So, I'm getting power to the DME, but nothing seems to be coming out. So, my symptom is different from Harvey's (the OP of this very old thread), who wasn't getting power to his DME. Can you think of anything that could cause this symptom, other than what I fear it is, which is a dead DME? And I can't imagine why a faulty alarm module would cause my symptoms, especially the lack of a blinking CEL, but if you think this could be contributing, I suppose there's no harm in bypassing it per Clark's Garage's instructions. Thanks.



Vliegwielolaf,



It can't be the hall sender, as this wouldn't cause a complete lack of a spark.
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#26

check the chip



also, i'm not sure if ours does it, but on some cars when the alarm module goes into protection mode, the car won't start. try pulling the alarm fuse. the ECU may require a reset though.



do the "11 second" thing to clear codes.
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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

How would I check the chip? It's a RacerX, which was installed by the previous owner about 7 years ago, so it's been in the car ever since I've owned it.



Yes, I've heard problems with the alarm could cause the car not to start, but I don't understand why this would prevent the blink test from working, but pulling the alarm fuse is a good and simple idea. I'll give that a try.



I'll try the 11 second thing, although I think I held the throttle to the floor at least that long last night waiting for the CEL to start blinking.
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#28

make sure it's seated properly. try a different chip.
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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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#29

I am not sure how the DME responds to a lack of signal from the alarm. If it boots but won't allow the car to start, or ? I would certainly look to see if the alarm module is signaling or not and/or have someone attempt to check codes with the alarm module disconnected or disabling.
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#30

Flash,



Yes, trying my stock chip (if I can find it...) had crossed my mind; I guess I have nothing to lose by giving that a try. And I will go ahead and disable the alarm by pulling the fuse to see if that does anything.
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#31

OK, I



- Pulled the alarm fuse, and tried blink test again. Same result - no blinking

- Took out the DME, took the cover off to look for any obvious issues (loose solder joints, etc.), and didn't see anything obvious

- Replaced my RacerX chip with the stock one, tried the blink test again, and again, CEL doesn't blink.



Remember that I don't have a functioning DME relay, so I'm forced to jumper across the DME relay terminals that close the circuit for the DME (terminals 87 and 30). Is it possible that the blink test for some reason wouldn't work with the actual DME relay in place? I can't imagine why.



Running out of alternatives to a dead DME, although I can't imagine what could have happened in the nearly two years it's been sitting idle that could have killed it. Maybe I jostled it while I was installing my gauge panel and jarred something loose.



If it is the DME, does anybody know of anyone who can test and (hopefully) repair them? Thanks.
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#32

These guys can check your DME http://www.ecudoctors.com/
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#33

Thanks, Dave. It seems ridiculous to throw it away, as it's probably just a specific component that's gone bad. I'll get in touch with these guys.
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#34

they're pretty good. i've used them before.
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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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#35

How does pulling the alarm fuse allow the 'OK' signal from the alarm module to reach the DME? I would suppose the alarm would still disable the car with the fuse out.
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#36

i'm not sure how the alarm works in this car, and if it even disables the car at all. if it's a simple in-line system, then pulling the fuse eliminates that circuit. in that case, if the fault was in the alarm, it would be bypassed. if there is a check in the logic, then the ECU will look for it and then decide whether or not to allow further activity. it was a simple thing to try.
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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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#37

There is a signal wire from the alarm unit to the DME. If it's not hot, no start. Pin 7 on the 14 pin DME connector in the passenger footwell.
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#38

In the link Joel provide in Post #19, it says to disconnect the alarm module, and then jumper a pair of terminals in the alarm module's connector. The idea is to rule out a faulty alarm module as the cause of a no-start problem. Does removing the alarm's fuse accomplish the same thing? As I think about it, it doesn't seem like it would. In fact, couldn't remove the alarm module's fuse cause a no-start condition (don't know - just asking)?



I doubt a faulty alarm module is the culprit in my case, because I don't see how a faulty alarm module could cause the blink test to stop working. But just for completeness, I may go ahead and try to bypass the alarm module to see if it changes anything.
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#39

this is why i think you need to get to a durametric. the guess work is going to kill you.
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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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#40

[quote name='flash' timestamp='1357878477' post='137293']

this is why i think you need to get to a durametric. the guess work is going to kill you.

[/quote]

I don't disagree, and I may well be getting one soon. However, in reviewing the DME troubleshooting guide in the manual, there are actually a very small number of items listed that can create a no-spark condition like mine - most of the items the Durametric or Bosch Hammer seem to be helpful with are things to track down once the engine is running, like subtle problems with the various sensors. So, while I'm waiting for the spare DME a member here has very generously mailed me, I'm planning to go through those few items manually. I do fear, however, that once I get this beast running, I'm going have a host of issues on my hands that a Durametric could be helpful in tracking down.



Does the Durametric work with a Mac? I don't own a Windows laptop, and cringe at having to buy one just to be able to use a Durametric, as I wouldn't have any other use for it. Especially after getting a bid of over $4000 on a siding replacement job for the top panels on my chimney...
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