DME destroyed?
#61
Drifting
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What exactly were you testing? Despite photo quality rivaling most UFO films, Bigfoot sightings, and alien bodies collected in the 50's, I can't quite make out which pins your leads are connected to, and am curious if the speed/ref connectors are connected or disconnected under the hood?
#62
Drifting
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I just pulled out a spare sensor and it measures almost exactly 1000 ohms across the two primary signals (just like Clarks says it should). I also tried all combos of the grounding shield, casing and signals to see if something is close to what you are seeing and couldn't get anything like that. Seems unlikely you'd have two identically bad sensors (unless you bought the wrong ones?)
Glad you like my filming and photography skills
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#63
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Ah, sorry, I get it. Those actually look ok then -- it's telling you the sensors have about 780 ohms, which is about right. The lack of tach bounce and your inability to get a ref pulse on the scope (despite getting it on the speed sensor) still would make me look at that sensor closely.
#64
Drifting
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Ah, sorry, I get it. Those actually look ok then -- it's telling you the sensors have about 780 ohms, which is about right. The lack of tach bounce and your inability to get a ref pulse on the scope (despite getting it on the speed sensor) still would make me look at that sensor closely.
OMG... could I have damaged the little stud?? Just say "no way". Please....
#65
Drifting
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And.. you are certain this attempt, the .5s 1v with trigger, doesn't show a pulse? To me, it looks like it pulses about 12 times across the screen--over 8 horizontal divisions until I stop:
Let me try my math again... if each division is .5s, that means the dot covers 4 seconds. At 200rpm, and 1 pulse per revolution, that is (I think) 200 pulses per minute or 3.3 pulses per second (200 divided by 60). Over 4 seconds, that should be about 13 pulses (if 200rpm). So, if I count 12, that's about right, no?
Or.. are you saying in that particular video, those aren't actually pulses?
Let me try my math again... if each division is .5s, that means the dot covers 4 seconds. At 200rpm, and 1 pulse per revolution, that is (I think) 200 pulses per minute or 3.3 pulses per second (200 divided by 60). Over 4 seconds, that should be about 13 pulses (if 200rpm). So, if I count 12, that's about right, no?
Or.. are you saying in that particular video, those aren't actually pulses?
#68
Drifting
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Got it. I don't have cruise & don't recall seeing any switches by the pedal; for a brief moment, I thought my no start was because I haven't been pushing the clutch pedal ![Smilie](https://rennlist.com/forums/images/smilies/smile.gif)
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#69
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And.. you are certain this attempt, the .5s 1v with trigger, doesn't show a pulse? To me, it looks like it pulses about 12 times across the screen--over 8 horizontal divisions until I stop:
Let me try my math again... if each division is .5s, that means the dot covers 4 seconds. At 200rpm, and 1 pulse per revolution, that is (I think) 200 pulses per minute or 3.3 pulses per second (200 divided by 60). Over 4 seconds, that should be about 13 pulses (if 200rpm). So, if I count 12, that's about right, no?
Or.. are you saying in that particular video, those aren't actually pulses?
Let me try my math again... if each division is .5s, that means the dot covers 4 seconds. At 200rpm, and 1 pulse per revolution, that is (I think) 200 pulses per minute or 3.3 pulses per second (200 divided by 60). Over 4 seconds, that should be about 13 pulses (if 200rpm). So, if I count 12, that's about right, no?
Or.. are you saying in that particular video, those aren't actually pulses?
And are you 100% sure you didn't mix up the speed and ref sensor connectors?
#70
Three Wheelin'
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OK I have re-read the post and would like to make some quick suggestions.
1. You have no spark. Concentrate on this don't think about anything else. Analyze everything on that car that makes it spark.
2. Think about things you disturbed. The gap? The three sensors? Switch them into the different plugs you may have switches them.
3. If you are certain that they are plugged in correctly have someone crank the car while you wiggle all those wires on top of beellhousing. You might get lucky.
4. Not likely but not unheard of, disable the alarm, jump the airbag module. Very easy to do and eliminates those possibilities.these cars are wired that if the airbag deploys it shuts off the DME
After you do all that work your way back from the plugs to the computer.
1. You have no spark. Concentrate on this don't think about anything else. Analyze everything on that car that makes it spark.
2. Think about things you disturbed. The gap? The three sensors? Switch them into the different plugs you may have switches them.
3. If you are certain that they are plugged in correctly have someone crank the car while you wiggle all those wires on top of beellhousing. You might get lucky.
4. Not likely but not unheard of, disable the alarm, jump the airbag module. Very easy to do and eliminates those possibilities.these cars are wired that if the airbag deploys it shuts off the DME
After you do all that work your way back from the plugs to the computer.
#71
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OK I have re-read the post and would like to make some quick suggestions.
1. You have no spark. Concentrate on this don't think about anything else. Analyze everything on that car that makes it spark.
2. Think about things you disturbed. The gap? The three sensors? Switch them into the different plugs you may have switches them.
3. If you are certain that they are plugged in correctly have someone crank the car while you wiggle all those wires on top of beellhousing. You might get lucky.
4. Not likely but not unheard of, disable the alarm, jump the airbag module. Very easy to do and eliminates those possibilities.these cars are wired that if the airbag deploys it shuts off the DME
After you do all that work your way back from the plugs to the computer.
1. You have no spark. Concentrate on this don't think about anything else. Analyze everything on that car that makes it spark.
2. Think about things you disturbed. The gap? The three sensors? Switch them into the different plugs you may have switches them.
3. If you are certain that they are plugged in correctly have someone crank the car while you wiggle all those wires on top of beellhousing. You might get lucky.
4. Not likely but not unheard of, disable the alarm, jump the airbag module. Very easy to do and eliminates those possibilities.these cars are wired that if the airbag deploys it shuts off the DME
After you do all that work your way back from the plugs to the computer.
#72
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You are getting good help and sound advise here.
You are missing ignition. How about fuel?
Did you verify the injectors are firing or not? If the injectors are firing, the Ref/Sync are not your problem.
You are missing ignition. How about fuel?
Did you verify the injectors are firing or not? If the injectors are firing, the Ref/Sync are not your problem.
#73
Three Wheelin'
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That is Why I was suggesting Spark.. Make sure it happens, If you see spark THEN worry about fuel, After all they only need three things to run... You have confirmed no spark. When You confirm you have spark then move on to fuel, but I have a feeling if you get spark it will be running. Pretty sure its getting air cause you're still breathing and its not underwater, LOL
I Forgot to add something in my last post that you wrote that is KEY here... THE CAR RAN BEFORE THIS WORK WAS DONE! You have eliminated the computers,, - It stands to reason that Something went wrong in performing this work.
You can look Down the Hole to see if that allen screw is still there. its supposed to stick up 5 mm and the gap is 0.8mm **You only need one ref sensor to make it run** My Spec Clutch only has one allen screw in it...
If you removed the bracket for the speed sensors then you WILL have to re-adjust it I made a tool to do this out of a piece of round stock and a slide collar to do mine.Hold it against the sensor with the The GAP is Critical!
And after seeing your harness I would Replace it... Its CHEAP insurance, After all the car is not getting any younger..
I Forgot to add something in my last post that you wrote that is KEY here... THE CAR RAN BEFORE THIS WORK WAS DONE! You have eliminated the computers,, - It stands to reason that Something went wrong in performing this work.
You can look Down the Hole to see if that allen screw is still there. its supposed to stick up 5 mm and the gap is 0.8mm **You only need one ref sensor to make it run** My Spec Clutch only has one allen screw in it...
If you removed the bracket for the speed sensors then you WILL have to re-adjust it I made a tool to do this out of a piece of round stock and a slide collar to do mine.Hold it against the sensor with the The GAP is Critical!
And after seeing your harness I would Replace it... Its CHEAP insurance, After all the car is not getting any younger..
#74
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I haven’t read the whole thread, but if no spark, did you jumper the KLR to rule that out? It Receives a signal from the DME and returns a signal to allow spark to occur under cranking. The Porsche test plan has details on the jumper procedure, it’s KLR pins 9 and 16 for jumper.
#75
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By the way, does your boost gauge show 1 when the ignition is on and the motor not running? That's a good proxy to confirm your DME/KLR is getting power. To John's point about fuel, if memory serves, he confirmed fuel in the cylinders after cranking, though not necessarily an actual pulse. But point taken. I'm with GPA951s in general -- all the o-scope stuff is interesting and educational, but going back and checking your work is likely more fruitful (and bypassing the KLR to rule it out, and wiggling the wires, and backing your way through the system from the spark plug to see where the spark failure starts).