944Phil

Mdj, before installing chips it might be best to fix the problem. I don't see how chips can solve a no start problem.

Just my $0.02

jsmith831

Mdj, I have the same exact problem. I found it was a compilation of problems that gave me those symptoms. The no-start after a moderately long period of time for me was a low voltage issue due to the power window relay. Feel with your hands after its been sitting for 2+hrs and see if the power window relay is still warm. It was slowly draining my battery. I am almost certain my other no-start issues are reference sensor related.

User 52121

I had this exact same issue a few years ago, see this thread: https://rennlist.com/forums/944-turb...art-issue.html

Cliff's Notes: a new (used) AFM fixed it. The door inside my AFM, when hot, would get sticky just off of being closed.

mdj577

All great and greatly appreciated advice.

Update: No problems starting cold this morning. Started but needed prolonged cranking after sitting for about 2hrs in parking garage. Hoping to continue to get lucky until I get it in to my mechanic.


944Phil : Yes, will do.

jsmith831: Will check window relay. In fact my passenger window is much slower than the driver side window. Could be related?

OmniGLH: Thanks. Will read your no-start post tonight.

mdj577

Well just read your post now. Like dejavu, my EXACT problem. Question now is will it share the same root cause. Thanks!!!!!!

mdj577

Update: 48 F here this morning. Started perfect first try at about 7am. Going to re-start at about 1:00pm.

quinnfiske

944Phil, your post caught my eye. I spotted those brackets on Paragon's sight and it started me thinking. My car has had speed/ref sensor issues even after replacing sensors, sensor harness (from Lindsey) and had the DME re-soldered.

I am wondering if an EMI pulse from the starter could be the culprit here? The sensors have shielded cables, but the connectors are not. The problem always occurs during cranking but the car runs fine when the engine fires and the starter drops out.

I wonder if the problem could be viewed on an Oscilloscope like the factory recommends?

mdj577

Update: Re-start at about 1:00pm. Air temp ~60F. About 5s of cranking then fired up. Ran smooth as usual.

gregeast

Here's a link to a thread I started a few years ago on re-soldering the DME after experiencing similar issues to what several of you are describing. There are a couple of good pictures in this thread to guide you.

https://rennlist.com/forums/924-931-...ed-w-pics.html

User 52121

If it was truly 5s, that's kind of a long time. Was the tach bouncing throughout the entire 5s? Or was it flat at first and then started bouncing partway through?

mdj577

I wouldn't exactly call it bouncing, but sort of pathetically wiggling down near the first mark on the rpm gauge the whole time it was cranking. Then when it finally fired up it was not exactly a robust start. After I gave it a rev or two it ran perfectly, as usual.

User 52121

Ok to me that would rule out a reference sensor issue

ehall

I agree. It is still worth checking the wires, but it sounds like you have another issue. How much voltage are you getting at the battery? I'm not asking because you may have a weak battery, though that could be true, but I'm wondering if your alt is working properly.

I try to eliminate the obvious easy stuff, before I go looking for complicated stuff. That way you have a proper baseline for trouble shooting. It could be something as simple as a worn Alt belt that expands a bit when hot.

dmalo810

We had the same issue in an 86. Long and behold, after replacing everything including trying new DME box, still no start. Last resort, bypassed the alarm box (info on Clarks garage on bypass). Boom, starts every time.

samcknig

Since I started this thread I have replaced some things and haven't been able to fix my issues. It seems to be getting more frequent now. When the car starts properly, I will see the tach bounce a couple times then the car will start right up. But the last 2 mornings, I will crank the car, there will be no tach bounce at all, and it will crank for 20 seconds without starting before i give up. I will try a few more times with no luck. Also, when I do get it to start, I have never once had it die on me while driving.

Things I have tried:
- Replaced speed and ref from the sensor all the way to the DME
- Tried tapping my feet on the passenger footwell thinking it might be a loose solder in the DME. No help.
- Replaced the DME relay a few times now
- Jumpered the alarm to make sure that's not the issue

What do I try next? There isn't a good shop in my area so I think I am pretty much on my own.