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Bizarre problem - DME fried?

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Old 07-23-2012, 11:46 PM
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Mancuso
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Default Bizarre problem - DME fried?

I'll get right to it. '86 951... engine will not start, but tries. With the ignition in the ON position, I can hear the fuel injectors "ticking" randomly as well as the ICV going into spasms. A strong fuel odor is present.

Is the DME and/or KLR fried?

Is there anything else that could cause this anomaly?

With much appreciation,
Mancuso

Last edited by Mancuso; 07-24-2012 at 12:25 AM.
Old 07-24-2012, 12:25 AM
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Fara
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Does the engine turn over at all and just not start?

The strong fuel odour sounds to me like a FPR or related component failing and spilling all your high octane goodness across the engine and floor.
Old 07-24-2012, 12:26 AM
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Mancuso
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The engine turns over, yes, but does not start. The FPR is new. The component spasms are what's concerning me. If the DME is toast somehow, I would shudder to think that it fried my Vitesse gear.

I think it's important to point out that the car was performing perfectly this afternoon.
Old 07-24-2012, 12:33 AM
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Fara
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If you're getting spark and obviously getting fuel, something's going hinky.

I'd try with a known good DME - If one's not available, I came across one on Lart's shop while picking up an oil cooler housing yesterday.

http://bit.ly/OkbpTW
Old 07-24-2012, 12:38 AM
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Mancuso
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Thanks for the response, by the way.

Yeah, I was eyeballing that set earlier. Mainly to get a feel for the going eBay price. I would hate to immediately resort to buying a DME and KLR from eBay if it's something else.

I've searched high and low on various forums and have yet to find symptoms like the ones I described.

Rennlisters... anyone here willing to sell/trade a DME and KLR? I have many goodies. Any other suggestions?
Old 07-24-2012, 02:23 AM
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Fara
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I was just thinking about this a bit further,

Have you cleaned all the grounds? It's a bit of a random solution, but if the grounds are intermittant it may report a flickering similar to your issue.
Old 07-24-2012, 12:21 PM
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Mancuso
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The grounds are good (shiny and new). Everything was spot-on perfect until that evening.
Old 07-24-2012, 02:14 PM
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Dino V
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I have somewhat similar issues with my '91 S2 Cabrio. Except mine won't start unless I keep the gas pedal down and then puffs rich for a few minutes after start up. I ordered a Stribel DME relay and fuel injection temp sensor that I am hoping cures the issue. I replaced fuel pump/filter, spark plugs and wires, fuel pressure regulator, distributor cap/rotor, etc.
Old 07-24-2012, 09:58 PM
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F18Rep
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Maybe you can guess and jump to the right fix but that almost never works for me. Heck if I swapped in a DME/KLR with my luck - it would get damaged too, then I'ld really be pissed....

Do you know you have spark? (simple ignition spark tester - $8 seen at HF). Do you know you have fuel pressure? (a little bit special fuel gauge - $30). Do you know you have injector pulses? (noid light - $15 any autozone, napa etc)....Bruce
Old 07-25-2012, 12:13 PM
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Mancuso
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I'm working down a list of checks now.

I greatly appreciate the information, folks. I will update this thread on progress/concerns/emotional outbursts.
Old 07-25-2012, 12:54 PM
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szabon
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Maybe there is someone near you that can swing by and swap dme's with you just to test. Who's in Texas?
Old 07-25-2012, 01:02 PM
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OntarioTurbo
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You mentioned that with the key in the on position you can hear the injectors and smell fuel. From what I've read, the fuel pump doesn't start pumping until it sees a signal from the crank sensor. Which means you have to be turning motor over. If you are pumping fuel just when the key is in the on position then perhaps it is a bad DME relay or fuse box.

Try hooking up a gauge to your fuel rail and check the pressure there. Fuel damper could also be faulty.
Old 07-25-2012, 01:14 PM
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John_AZ
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When I replaced my AOS seals and stuff, I left the AFM plug off. The car will not start with this plug off.

If your car was running perfect clean the AFM connection and move the inside door to make sure it is not binding.

And since I do not see the obvious question asked---When you turn the key to crank ---do you see the tach bounce 1/16th of an inch?

Just another idea.

John
Old 07-25-2012, 01:35 PM
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Paulyy
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by any chance did you somehow get any water in the DME?
Old 07-25-2012, 01:56 PM
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Ben951S
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Gotta start with the basics man...

Does the tach even bounce when trying to start?

Also, have a fire extinguisher handy. Why are you smelling fuel with key on! Fuel pump shouldn't even be running. Can you hear it run with just the key on?


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