eric951turbo

So I decided to start a new post on my problem, with a new title.

The old thread I did (http://www.benms.com/944nostart.html) didn't get a lot of hit, and I really hope getting help solving this problem.

Now the problem is this:

944 turbo, 86, engine starts fine, first shot, let it warm up, no problem.

Go for a ride, as soon as a start accelerating, the engine dies with a big backfire.

Then I need to wait a good 2 hours before it will start up again.

So far:
- Changed the coil
- Changed the distributor
- Changed all spark plugs and wires
- Checked the rotor, it was fine and tight, the screw still in position (Changed it for precaution 3 months ago)
- Checked all vacuum hoses and intake hoses, all nice and tight
- This all the tests from http://www.benms.com/944nostart.html
- Getting sparks
- Fuel pressure is good and also as the fuel pump (also did the jumping the dme relay, everything worked)
- Checked the voltage at relay terminals, all good (12v)
- The TPS is fine
etc... etc...

I huge thing I notice is that when I'm able to start the car, the dash is reading 1.1 to 1.2 bar... AT IDLE? But my psi gauge is fine, reading -18psi???

Can someone help me on this... please!!!

931guru

It could be that the KLR is defective and is going into a weird version of overboost control. If you have a friend with a 944 turbo, now is the time to take your DME and KLR over to his car and swap them in one at a time to see if the symptom follows the parts.

MAGK944

I know this is obvious and simple, but have you checked your engine/DME main grounds? I had similar symptoms when I forgot to tighten them once, as soon as I got moving the engine cut and it was a lottery when it would start again. Had instrument issues like you also at the same time.

eric951turbo

Yes, I've cleaned all my grounds 3months ago, trying to find out a running rich problem but turned out to be a crack in the intercooler hose coupling.

Again, as the the previous post, this new problem happened right after I washed my car. Maybe it's not related, maybe it his.

eric951turbo

But again, a good suggestion (I'm sure they are tight as hell, but you never know). I'm just getting tired of removing that intake and fuel rail, I've already removed it 4 times this season.

More suggestions are welcome, I don't know what to do anymore.

The car was running amazingly, for the last 4 days.

StoogeMoe

I didn't see "Remove AFM connector, clean, and plug back in" in your list.

You might also want to do that with your reference sensors.

eric951turbo

Did the reference sensors cleaning, unpluging etc... and I a vitesse maf, 2 years old... looked inside the maf pipe and looked brand new.

sorry I forgot mentioning both reference and speed sensors in my post.

MAGK944

Battery compartment drain hole blocked, corroded panel below battery causing water into DME, clutching at straws here...

ZR8ED

hmmm. Backfire eh? Backfire equals fuel burning in the exhaust pipe...Are you sure your FPR is ok? Mine acted up for a day or two, then completely failed. It would idle for a few seconds then die as the fuel pressure spiked. Watched it with a guage on the rail..It would hit 100psi in a split second. I could eventually restart it..until it spiked again.

eric951turbo

true, the battery compartement hole was blocked, I cleaned it yesterday.
I after looked at the computer and the foot well, there was some humidity, but not real water.

I then put a hair blower in there for 15 min., everything was dry.

So you think the humidity could of cause the dme or klr to short down?

eric951turbo

Purchased the new 3bar fpr with the new vitesse maf kit 2 years ago.

Didn't put any fuel stabilazer last year.... the car was in my garage, and I worked on it all winter.

Could be the cause... but no real way to check it... right?

Like I said, the car was running fine before I washed it.

MAGK944

I doubt just humidity would do anything, I'm in FL with 80-90% humidity at most times with no issues. But if water dripped onto the dme it can easily get inside.

Saying that it doesn't seem like a dme issue. Normally it's the large power resisters in there that go first. In fact the solder joints to those resistors get brittle from heat cycles. A failing dme normally gives you a warning, engine doesn't fire, then fires. Eventually the doesn't fire gets longer and you have to bash the dme to get it to start.

It's always difficult to diagnose a problem such as this remotely. If you can get hold of a dme/klr and swap them in, that would be a plus.

eric951turbo

back to you on a failling dme part... thanks, I needed to know that.
I always thought that a dme worked, or didn''t worked. I've been working with computer since 1995, all Mac's... when they are fried, they are fired, nothing to do.

JasonLP, here on rennlist, I saw him yesterday, he has a good DME and KLR and told me to try them in case. I haven't, because I'm so hard headed. Could believe that could be the problem.

But will.

I've just trying to get as many recomendations, stuff I haven't tried before changing the dme/klr.

The worst part is that I have an appointentment to the body shop tomorrow at 8am... I was test driving the car nearby this afternoon when it quits.

I then called my wife with the 4runner and she towed me all the way to the body shop... they have the car until thursday.

So no more tests for me for a couple of days,

But recommendations are welcome.

968 GUY

Blow off valve broken.

eric951turbo

That would cause the engine to stall??? I'll try it! I still have my oem one.