1984 3.2 will not start

[198491132]

I cleanded the grounds, checked the ground strap on the tranny as well. I get 12v when the key is "on" at the coil. I get a single spark when the key is turned on, but no spark when cranking (laying plug on cyl head as ground).

Dave

[Darren]

I don't know how different the Motronic is from my 944, I don't think that much different.  I had a short in my coil circuit that burned through a trace on the board.  I soldered it back together.  I agree swapping it out is the easiest way to not waste too much time, but you could also just take it apart and see if there is any obvious damage to the board.  Even better if you know what pin to trace out to see if everything looks ok.

With the amount of current going through there I'm guessing if the coil circuit is bad you might actually be able to see it burnt.

[198491132]

Gave a visual this morning and nothing looks burnt in the DME ..and no smell of burning. Voltage at the coil primary is 12.72 and 12.75...so the coil circuit is good. I may have someone to help with a DME swap out, (fingers crossed) not sure what else is could be.

Question, how is the best way to view and measure the flywheel sensor distance?

The only tests I have done on it are to measure ohms...and the smell of gas at the exhaust pipe after cranking. Are these two tests good enough?

 

Dave

 

[MylesD55]

 

Viewing the distance is tough with the engine in the car, but I think that you can just barely see it.  The measurement is set out in the manual, but a matchbook's thickness is close enough.  Just make sure it is not rubbing the flywheel and destroying itself. 

Myles 

[ccm911]

Could there possible be gunk between the sensor and the flywheel?  I wonder if you could spray in something like Brake Cleaner or Electronic cleaner to see if that does the trick.  And if you could actually see the sensor, I am wondering if you could just get in there with a small screwdriver(or allen wrench) to see if the sensor has become loose?

[198491132]

Best way to see/clean...the sensor? From underneath the car or through the engine compartment?.

I have noticed a lot of the sound deadening material falling apart in the engine compartment, but, geeze...I would hope it would not get into the gap.

 

Dave

[198491132]

Swapped my DME unit with Vidal's (thanks Vidal!)... it started his car, the unit is fine. I am going to try to get a better look at the sensor. Not sure how to get an eye ball on it....any tricks well appreciated.

Thanks, Dave

[Larry Herman]

Use a Boroscope.

[198491132]

Great idea Larry, thanks, will get one. I am going to check these sensors closely.

This thing looks like something my Doctor would use...... 

[ccm911]

I have another idea.  Could this possibly be a bad ignition switch?