Dan Martinic

I put test leads into pins 25 & 26 (ref sensor) then did the same with 8 & 27 (speed). All connected under the hood.

Dan Martinic

I bought the FAE ones. I will check Clark's routine again, but I do recall going over his material initially and being satisfied with what I got.

Glad you like my filming and photography skills

Tom M'Guinn

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.

Dan Martinic

Is it possible that I've knocked out that stud the ref sensor reads? I did have some trouble fitting the bellhousing... actually, I remember stupidly trying to force it on while the bracket was installed; I gapped sensors with a feeler gauge, removed them, then totally forgot about the aluminum shield. After much trying (and at one point even rotating the motor a bit to see if anything was catching), I realized what I forgot, removed the bracket, and fitted the bellhousing.

OMG... could I have damaged the little stud?? Just say "no way". Please....

Dan Martinic

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?

Dan Martinic

We have a clutch switch?



(image is from post #25 on the following thread: https://rennlist.com/forums/924-931-...i-fried-2.html )

PaulD_944S2

Yes, it temporarily disconnects the cruise control while shifting so the engine doesn't over rev while in neutral.

Dan Martinic

Tom M'Guinn

No not certain at all. It's possible, somethings happening there, but the trigger isn't working and the time divisions are too long to really see the wave form. But I agree that video suggests something is happening around the right time. The S100 output going to the 8051 interrupt pins are easier to watch on the scope (simple 0 or 5v square pulse trains) so maybe that would be an easier way for you to see if both sensor signals are working.

And are you 100% sure you didn't mix up the speed and ref sensor connectors?

GPA951s

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.

Tom M'Guinn

Very sound advice.

fast951

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.

GPA951s

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..

GreyDog

Tom M'Guinn

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).