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Help!

So i was trying to figure out what was wrong with my car, and in the process, i took out the MAF sensor, and cleaned it. then re-installed it. I took my distributor cap off again, and found that the button had a crack all the way up it. so i went, and found a new one at auto zone. Got it on.

When i went to start it, it fired, and run for about half a second, then dies. It couldnt be the ditributor, so i unplugged the maf, and fired it. and it did the same thing. so i re-installed if about 3 times, now result.

What could this be?
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Old 04-27-2010, 08:10 PM
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Was there something going on previously that prompted the AFM cleaning, etc? Was it having this problem you describe all along, or something else and now it's worse, or it ran fine and now it doesn't?

You should add your car model and year in your post signature so everyone knows right away what they're dealing with.
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Old 04-27-2010, 08:19 PM
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That's a good point, it's an 85.5 944 NA.

It's been sputtering, and driving pretty bad latley, it was just trouble shooting to clean the AFM. i have another thread on this page about what it had been doing. it ran, but now not at all
Old 04-27-2010, 08:23 PM
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YouTube - Rejuvenating a Bosch Motronic Air Flow Meter

This almost describes my problem. hesitation at certain rpms, etc. could this be it?
Old 04-27-2010, 08:32 PM
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Just guessing...

I had an intermittent failure of the DME relay that presented a bit like that. Replace or bypass ( 87, 87b, then 30 in that order) the DME and check.
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Old 04-28-2010, 09:16 AM
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I just don't know why now, it's not starting at all. when before it ran.
Old 04-28-2010, 11:17 AM
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The AFM sensor could be it and would definitely be worth a look, but have a look at the DME relay. The DME relay can go bad at a moment's notice on these cars and that cuts power to the DME and the fuel pump. It could also be a vacuum leak from deteriorated vacuum hoses (large ones under the intake manifold especially) or cracked intake J-boot, wrong or weak fuel pressure from a clogged fuel filter, clogged fuel tank pickup screen, bad fuel pressure regulator, bad fuel pump wiring, or bad fuel pump, could be worn or fouled spark plugs, burned distributor/rotor contacts (shouldn't be since it's new), bad ignition wires grounding out, clogged or stuck injectors (try some seafoam in the gas), bad injector wiring (fuel rail can be removed with injectors still attatched and motor cranked to verify good spray pattern and all of them firing...disconnect ignition coil voltage supply first!), improper signal from oxygen sensor (run engine with it unplugged to test), bad wiring to AFM (needs to be getting 5v from the DME and a smoothly increasing voltage with increasing flap angle returned to the DME. It will sputter and die without the AFM signal.), DME coolant temp sensor could be bad, bad connections at the auxillary primary wires at the positive battery clamp that supply power to everything on the car... The list goes on. Check the easy stuff first and work your way down the list.

DME relay info
DME Relay Information and Testing

A good collection of repair proceedures you should bookmark.
Clark's Garage Shop Manual Index

The source of info for the youtube vid above.
Air Flow Meter (AFM) - from "The 944 Motronic DME" by FR Wilk

DME plug pinout. Notice how the random numbers designated on the AFM plug on the link above actually correspond to the DME connector pin number.
http://www.the944.com/connector.htm

Let us know how it goes.
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Last edited by HondaDustR; 04-28-2010 at 12:01 PM..
Old 04-28-2010, 11:49 AM
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Thanks for all the advice, the problem started awhile ago, and i got a new fuel filter, and it ran allot better for a little while, then i ran some seafoam through it. and noticed an okay difference, but i'm on the tank of gas after the foam,and i'm lost. If i could get it to run. then i'de have somewhere to go. it quit running after took the afm sensor out. i've un, and re-installed it many many times. and it's starts, revs to about 1200, the immediatly dies. every time.

Last edited by tayloray; 04-28-2010 at 12:11 PM..
Old 04-28-2010, 12:06 PM
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Snapped this pic of my fuse box. I have two dme's? i switched them, and it would start at all, and it wouldnt start with either out
Old 04-28-2010, 12:37 PM
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I think i may have messed up my whole air flow meter. Maybe when i put it back in? it've tried to put it in multiple times, and it does the same thing with it unplugged, fires, revs, dies. and if i touch the gas when firing it, it dies instantly
Old 04-28-2010, 04:05 PM
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anyone? i'm lost right now, i have good fuel pressure, good spark. it just wont keep running. has to be a sensor fail right?
Old 04-28-2010, 04:58 PM
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Check the AFM with this procedure
Air Flow Meter (AFM) - from "The 944 Motronic DME" by FR Wilk
Take a deep breath and take your time, good luck
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Old 04-28-2010, 06:05 PM
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Quote:
Originally Posted by kfray View Post
Check the AFM with this procedure
Air Flow Meter (AFM) - from "The 944 Motronic DME" by FR Wilk
Take a deep breath and take your time, good luck
I searched for AFM earlier, and ran upon that. So with no toher options, i took it out, cut off the cover, to see the wipber bent all to hell. so i put it bent it back, and was curious why their where 3 arms when i remebered two. so i put it on the car, same problew. looked at the pictures again, and realized the farthest in arm was to be bent to the top. bent it up, put it back on, and now my car runs.

Test drive after school tomorrow.

A big thanks to everyone for their help.
Old 04-28-2010, 07:44 PM
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good job! You don't want to know how many times I've forgotten to plug that thing back in after a repair requiring its removal, so I'm quite familiar with how it runs (barely) without one.
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Old 04-28-2010, 09:17 PM
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I put it on to test it before putting the cover on, and remounting the airbix, so when i went to put it back on, i forgot to plug it and, and i was like WTF! then i realized it. haha

Old 04-29-2010, 01:04 PM
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