Airflite40

I have a no start problem.

I just finished doing an intake refresh on my car, did the venturi delete, all new vacuum hoses, put in a 3bar fuel pressure regulator, replaced injectors with cleaned ones, put in new spark plugs, newer spark plug wires, installed stock airbox.

I checked fuel pressure - good 3-bar.

I checked spark with timing light while I crank car - good.

All the new injectors and old injectors pass click test with a 9V battery.

Pulled spark plugs - completely dry, no trace of fuel smell look brand new.

I pulled off the fuel rail, disconnected the injector harness from the injectors, plugged 1 injector back in, put it in a water bottle, then cranked car.
No fuel in bottle.
Took out DME relay, put in jumper, cranked car.
No fuel in bottle.
Took off injector, put in one of the old injectors, cranked car.
No fuel in bottle.

The car always started on the first try. Sometimes when it was hot it would take two tries, but that is cuz one of the S/R sensor connectors is mangled.

The tach does wiggle when cranking.

What could I have screwed up to make the injectors not fire?

MichelleJD

I have a no start issue as well. Maybe we should put our heads together.

I'll be interested to see how this comes out.

schwank

Damn Borys, still fighting this one huh? At least it happens the same with both injectors. Did one of the S/R sensors get moved... since you said that wiring is funky.

Airflite40

I'm not sure about if one of the S/R sensors got moved.... Since the tach is twitching and I have spark I thought that means S/R are good?
I'm gonna swap out the S/R from my 924S tomorrow.

Is there any recommended way to get at them on a 951....they look tough to get to

quinnfiske

I would think if the S/R sensors are reversed or have failed, there would be no spark.
Sounds like you are not getting an injector signal from the DME.

Calmchaos

Why hasn't anyone said DME relay yet? (being serious, not sarcastic)
When I had no fuel my tach bounced so I replaced the fuel pump. Turns out it was the darn DME.

Airflite40

mmmm I have fuel....fuel pressure at the rail.

The injectors are not firing. I tried cranking with the original DME relay, my spare NEW DME relay, and jumper in place of DME.
All resulted in the injectors not firing.

I just tested my harness with a 9v battery, tested between pins 14 & 15 of the DME against pin 6 of the KLR (ground) and all the injector clips showed 9v strong.

I pulled the S&R sensors out of the 924S and it was a PITA, even with the intake removed.

I can't even see the S&R sensors on the 951 (its dark lol). Does anyone have any tips on getting to them besides pulling of the forking intake??

MichelleJD

Not only are they hard to get to, they usually get wedged onto the bracket. I actually had to cut one of mine out, ruining it in the process. I wouldn't pull them unless you had to.

Calmchaos

You take the bolt out on each one that holds the sensor in the bracket. After that odd shaped bolt is out, just grip them suckers up with your hand and twist and pull until they come out. I've pulled four that way.

If I knew for a fact they were broken I would clamp some vice grips on there and just rip at um. But just using your hands makes it harder to crack the plastic.

If you don't mind re-gapping you could take the whole retaining bracket out. That makes things much easier.

Airflite40

Well with the 951 I can't even see the sensors, there are more hoses and wires in the way....

I hope the broken one is the one closer to the engine cuz at least I was able to get a 10mm socket on it with the 924S.... I'll try and see what happens in a lil bit....

quinnfiske

I did not have a hard time with my 951. I used a long 1/4 drive extension to get the screws out and just reached down there to twist and pull them out. I did not touch the bracket so I would not get it out of adjustment. I have fairly small hands however.

Airflite40

Okay replaced the reference sensor with the bad connector, thankfully it was the front sensor so it wasn't that bad.

BUT stilll have no start. I can put in the jumper, put a any one of the injectors into a bottle, hit it with the 9v battery and get a nice flow of fuel.
When I crank the car, nothing.
The injector harness is good, verified it this morning.

I connected my multimeter to one of the injector clips.
When I turn the key to 'ON' I get 2v at the clip.

When I crank, there is no change in voltage.

I pulled the DME out and I will open it up to see if there is anything that looks funny.
Why the hell would someone spray paint my DME black???

Airflite40

Got the DME open, nothing looks funny.

I found out what chips I have the chip says

Superchips
944T Fuel
14857 24 PIN

If I can get someone to bring over a DME, is it safe to put my DME in their car or their DME in my car?

skene

You could have a short in your injector wire harness. I've found a short in one of the connectors which caused a nonstarting issue a while back. Mine was a viable short, so I'm not really sure how you can check it easily. Check for low/no resistance across different leads in the connectors with a volt meter.

Injectors for cylinders 1 and 2 are wired together into DME pin 15 and 3 and 4 are wired into pin 14. Check for continuity between them and make sure there is no continuity anywhere else.

Airflite40

i did check for continuity in my harness it tested out good see post #7.....