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-   -   No start (http://forums.pelicanparts.com/showthread.php?t=967047)

Toast54 08-19-2017 08:05 AM

No start
 
I've replaced the dragging starter and now I'm getting it to rotate. Still won't fire though.With the DME relay in, I get no fire from the coil, but if I replace it with the 3 wire jumper, ( per Clarks garage)then I get coil fire and spark plug fire... But still no start. Anyone have a next step in mind? I've tested the flywheel sensors and they come up good.

Bukowski 08-19-2017 09:07 AM

How's the gas?

I had to really flush my whole system out and clean injectiors - worked like magic.

You'll have to search for some of my writings on here to see details...

Bukowski 08-19-2017 09:09 AM

... "no fire from coil"

But I didn't have that problem.

Bradical 08-19-2017 09:56 AM

Quote:

Originally Posted by Toast54 (Post 9706205)
With the DME relay in, I get no fire from the coil

Sounds like multiple problems.

Jumping out the DME relay should instantly activate the fuel pump. The only issue that a DME jumper will solve is no fuel due to a bad DME relay, but a bad DME relay will not power pins 35 and 18 on the DME so the DME won't activate Pin 1, which is the ground for the ignition coil. I admit I thought the DME grounded pin 1 as soon as it saw 12v on pin 4 (start signal), but maybe that's incorrect- it's usually not a problem unless the ignition switch is bad.

I'd crank the car and see if I was getting 12v across 85 and 86 for the DME relay (at the socket) and pins 87 and 85b. If you have 12v across those two sets of pins while cranking, the DME relay is bad for sure.

Then, with the DME jumper or a new DME relay installed- you should verify that you have fuel pressure at the rail and that the fuel injectors are working.

Bukowski 08-19-2017 10:01 AM

I'd just get a new DME relay and not worry about it, move to the next problem....

how old is it anyways? What's it look like underneath?

Toast54 08-19-2017 10:16 AM

Another clue ( I hope). It will start after about 10 seconds of starter rotation WITH the throttle body wide open, sputtering and rolling black smoke from the tail pipe. Ill run some voltage tests
on the DME socket. I replaced the DME relay 3 years ago after a no start, used the 3 wire jumper to get it started, got it home and ordered a new DME relay, installed it and it started fine after that. Bukowski, its an 87 model and the undercarriage is in good shape. I'm not one to just throw parts at a car and hope they stick. Buy a relay, doesn't fix the issue and non-returnable.

Bukowski 08-19-2017 10:22 AM

Quote:

Originally Posted by Toast54 (Post 9706346)
87 model and the undercarriage is in good shape. I'm not one to just throw parts at a car and hope they stick. Buy a relay, doesn't fix the issue and non-returnable.

Of course that's a sound philosophy in general, HOWEVER, 944 owners tend to have two DME relays at all times.

944 Ecology 08-19-2017 11:26 AM

Quote:

Originally Posted by Bukowski (Post 9706354)
Of course that's a sound philosophy in general, HOWEVER, 944 owners tend to have two DME relays at all times.

I actually prefer the "two wire, three spade connector" jumper as an emergency fix. Cheap to make, lightweight, works on all 944 variants, and, did I say, Cheap!!!

I have at least one in every 944.

Toast54 08-19-2017 12:13 PM

Quote:

Originally Posted by Bradical (Post 9706329)
Sounds like multiple problems.

Jumping out the DME relay should instantly activate the fuel pump. The only issue that a DME jumper will solve is no fuel due to a bad DME relay, but a bad DME relay will not power pins 35 and 18 on the DME so the DME won't activate Pin 1, which is the ground for the ignition coil. I admit I thought the DME grounded pin 1 as soon as it saw 12v on pin 4 (start signal), but maybe that's incorrect- it's usually not a problem unless the ignition switch is bad.

I'd crank the car and see if I was getting 12v across 85 and 86 for the DME relay (at the socket) and pins 87 and 85b. If you have 12v across those two sets of pins while cranking, the DME relay is bad for sure.

Then, with the DME jumper or a new DME relay installed- you should verify that you have fuel pressure at the rail and that the fuel injectors are working.

I'm not getting 12v across either set of terminals on the DME socket

Bradical 08-19-2017 01:24 PM

If you have no 12v across 85 and 86 then I'd look at your ignition switch for the problem then.

Toast54 08-19-2017 03:15 PM

Quote:

Originally Posted by Bradical (Post 9706545)
If you have no 12v across 85 and 86 then I'd look at your ignition switch for the problem then.

Thanks for your help
It is cracked. No telling what the inside looks like.


http://forums.pelicanparts.com/uploa...1503180798.jpg

Toast54 08-20-2017 11:27 AM

Still won't start, though. Now it wont even turn over. Going to just walk away for a spell, I think

Toast54 08-23-2017 05:13 PM

After it started a few times, it then wouldn't start, so I pulled it this evening. The "cone" of the starter had broken, with the loose piece laying in the engine flywheel housing, along with the shaft bushing. I don't recall hearing any chunking or clunking. It looked like it had been dropped on the end, but I had to swear to the counterguy I hadn't I'm going to return it under warranty and try another. Should it happen again, is there something I may need to look at near the flywheel?

Slam 08-24-2017 08:26 AM

Very interesting. I understand the cars with the later, small-frame starter can do this if the speed and ref sensors aren't shielded (don't have their factory shields installed). EMF causes kickback on cranking that can actually break the starter. I have experienced kickback with my wife's 87 auto and it can seem pretty violent.

Toast54 08-24-2017 05:16 PM

New replacement starter, so now I can at least turn it over whilst I'm poking and prodding various terminals for voltage. I did find a disconnected tube behind the O2 sensor on the exhaust, but when I traced it down, it has a blue cap over it with a hose clamp

fiily 08-24-2017 05:43 PM

This one?

http://i.imgur.com/XB4ICVQl.jpg

Toast54 08-24-2017 06:04 PM

Yes

Toast54 08-26-2017 07:38 AM

Access for exhaust emissions, apparently not used

Toast54 08-27-2017 09:43 AM

Ignition coil
 
Still sorting this out. Per Clarks garage, I have tested the ignition coil and I'm getting 12V on both terminals. The output measure about 5900 ohms and the test across the coil nterminals measures.59 ohms, However, the spark appears to be rather weak. Can they test good good and still be weak output?

Toast54 08-27-2017 11:56 AM

Back to having tach bounce and starting (barely...with rolling black smoke and overpowering smell) with the jumper in, nothing with the DME relay in. Ive ordered one, guess will give it a shot..what's to lose, eh?


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