I was suggesting the bucket to feed the car fresh fuel, but after re-reading the original post I see that gas wasn't purchased around the time that the problem started happening....

How about measuring the output from the TPS/AFM at the DME?
Maybe a wire isn't doing its job...

I dont know the pin assignments, but I know some of them have been mentioned on the forums in the past.

I would definetely pursue the bad-gas hypothesis.

 

Thats one of the better suggestions I have heard in a while... I am also going to suggest that Aaron swap the ref sensor connections and try it, as its pretty easy to get those hooked up backwards when reassembling things (um, Aaron, be sure to swap them back if it doesn't... lol).

Regards,

 

i dont think its possible to switch them... im pretty sure the male and female connectors are reversed for each side, i.e. the left side the ref is a f/m connector and the speed is a male and vice versa on the other side. I will double check though. Anyone know where I can get a DME connector schematic, that shows what each pin goes to??? Thanx

By the bucket operation, you mean put good fuel in a bucket and run the line that goes from the tank to the pump on the bucket? And then have something to catch the return fuel that would be running out back into the tank and out the disconnected hose?

 

oh yeah and if they weren't switched the tach wouldnt bounce right? Cause I have unplugged them and no bouncy, put them back and bouncy, plus injectors are firing which wouldnt happen without proper signal right?


Thanx

 

Try a search on here, I know some of the pins have been listed...

I dont know if during your AFM switches you tried to just run with it unplugged... If you have a wiring issue, it would reveal it, unless the wiring issue is a short...then it may not.

Thats what I was thinking about the bucket of fuel, to me it just seems easier than cleaning out the tank... and takes another variable out of the equation.

 

tried running with it unplugged, nothing.

 

The reference and sensors are the exact same part, so they can definitely be swapped.

Regards,

 

Check for vaccum leaks also. I had a similar thing happen on my 944 n/a shortly after I bought it and I swore the bucking and surging was going to give me whiplash or snap the drivetrain or knock my fillings loose. It was BAD - ended up being just a small crack in the "Y" vaccum connector that goes to the fuel dampener & fuel pressure regulator. I replaced it and it's been smooth as silk since.

 

really??? That little of a crack caused that much!!! But it did start up! Which is more than mine is doing right now...

UPDATE: Drained fuel, looked clean. Flushed that Toluen (?) stuff through the whole system and it looked just as clean coming back out. Will put MORE fresh fuel in tomorow, with no results im sure

 

wiggle the injector harness at the rear of the fuel rail while running, if you can get it running for a few. If no try cranking it and have someone wiggle the harness around, may be a bad solder joint in the harness, sometime happens and WILL drive you batty trying to diagnose it. DMEs are different for different years along with the AFM, make sure you are swapping with the correct ones. I'm sorry if any of this was covered, I didn't read all the posts completely. Also, kinda goofy but a thought, check the running depth on the reference sensors, the whole bracket adjusts, it's like .6mm or something, please double check that spec before you readjust. I recall someone having this issue, the car warmed up and heat expansion pushed the sensors too far away to read correctly and died untill it cooled. The best way to set the depth in the car is using the proper thicknes washer or shim glued to either a bad sensor or temporarily to a good one, loosen the bracket, slide it down untill it contacts the flywheel and lock it in place, remove shim. You may have enough room to get a set of 45degree angled feeler guages in there, not sure.

 

I will try the harness thing. As for the depth of the sensors, if they are off a bit would it be enough to get a signal but a weak signal that might somewhat sporadic for the DME to read? Other than that I am getting spark so obviously the DME is getting some type of signal from the sensors.

 

Dude I think ive said this before but i cant do much better. Try taking the top off the airbox of and leaving the filter on the car. You could have sucked up a garbage bag or a racoon or something and you didnt know it.

Pull the top of the airbox if you havent already just to make sure you dont have any small animal chilling out in there. If not im all out of ideas

Try starting it with the top of the air box off so if you did suck up a monster it can breath this way.

 

I have a cone filter... So no dead animals. Plus I have tried starting with AND w/o the filter on. And if by some miracle the animal made it passed the filter (?) I would have seen it in (a) the intake boot (b) the throttle body OR (c) the intake manifold. No air obstructions what-so-ever. And all hoses looked great. Replaced some of the 5/32 vacuum lines on top too. Where else does air get out?

 

 

lol, I've been doing that for the past 2 months!!!

UPDATE: Alright, got it all drained, ran Toluol (?) through the whole fuel system, flushed it out, put in new Premium fuel and go to start it up, and BAM! It starts! (dont get too excited) It idled at 3000 RPM!!!!!! Then it hit me! There was probably still some Toluol mixed in with the gas making it SUPER Octane! Well anyway it idled at 3000rpm for about 30 seconds and promptly died, not to start up again. Tried the wiggle of the injector harness, nothing different. Then I noticed something!!! The tack is no longer bouncing !!!! Had my dad wiggle around the connectors and it bounced for a little bit then stopped again. But even when the tach bouncing it doesnt start, so that not THE problem, but must be fixed ASAP! AGH! So many things!