I think i found the problem

[Rock]

I did everything on clarks garage to try and find what the problem was with the car. Everything checked out fine. Then I looked at the electrical part of the ignition switch, when i pulled that out, the cover fell off and the wires went everywhere (that was hard to put back together). I checked that, and put all the wires back in, everything was with that.

Then I checked the sensors. The Speed sensor gave about 3 volts when cranking, and had a resistance of around .999 ohms.

The refence sensor had 0 resistance, and sometimes it would jump really high to like 39.34 or something, but mostly stay at 0. This sensor also had a voltage of around 1.7 when cranking.

Is this the problem?

Also, when the car first broke down, i would crank the car and all of the gauge lights would go off, and the gauges would even start reading (the oil pressure climbed to 5 and stayed up there, i saw the temperature and battery gauge move and start reading too). Now when i crank it, all of the lights stay on and the gauges dont read anything. I dont know if this is a problem, but for some reason it bothers the hell outta me.

Well thanks for your help guys, i think im real close to fixing it.

[Rock]

bump

[Rock]

thanks for all the help

[Brando]

You say you think you found the problem. What is it exactly?

[Rock]

I think the reference sensor is the problem. With a voltage of 1.76 at the dme plug and a resistance of 0 on the sensor.

[ae1969]

Do you have an extra sensor to swap. Easiest check.

If you tested them like it has been mentioned (manuals, and posts)........and its out of spec. ITS BAD.

The reference sensor not working = no spark, no injector pulse.

[Rock]

i dont have an extra sensor, i want to buy one, but ive already wasted so much money trying to guess the problem. Ive checked everything else out though and it looks like its the sensor, so im gonna go ahead and buy it. Where can I ref sensor cheapest? I know vertex auto has one for 90 dollars...

[AFJuvat]

$90 is about as cheap as it gets.

AFJuvat

[pokey]

I just got both sensors from a guy parting out a 44 for $25 incl. shipping. Look around for a used one. Also you might want to check that the sensor clearance is .8 mm, that could cause the fluky readings.

[lousailor]

Both my cars have had starting problems due to those sensors. On one my Dad took the car in to a garage while I was away, and the shop changed everything but the sensors including the cat. I got back and the problem started happening again. Same garage finally changed one of the sensors and the car worked fine until I bent it. My beater did the same, but I pulled both, replace one because the connector broke, and cleaned to other cause it was covered in gunk and metal particles.

[SoCal Driver]

Following proper testing procedures is strongly recommended. Otherwise the 944 becomes a money pit.

[Rock]

I followed proper testing procedures. I tested everything else it could be in the car! The coil is good, spark plugs are good, DME relay is good, DME is good, the wires, rotor and cap are good. The ignition switch is also good and so is the starter. They all had proper voltages and resistances. The only thing that didnt have the proper resistance was the reference sensor. It read 0 ohms, and would occasionaly jump to like 34.32 ohms or something like that.

[SoCal Driver]

Which of the three contacts were you testing across? One side is a floating ground. Is not supposed to connect to anything. The center and the other pin are the sensor core. 1.2k to 2k ohms.

[Rock]

i tested across the center and the pin to the left of that. It was terminal 8 and 27 i belive. Then i tested the same ones on the other sensor. One sensor red .999 K ohms, the other read 0.

Clarks garage said 600-1600 are the correct ranges... is 1.2-2k right?

[SoCal Driver]

Yep.

[ae1969]

my new sensors both read ~990 ohms.....

The one is definitely shot....

[Rock]

Thanks for all the help guys! Im real close to fixing it... im having a hard time getting the other sensor off.

[early_944]

hey, just a suggestion, make sure the wires to the sensor are good. If there is no resistance i.e. 0 Ohms it usually means there is a short.
the sensor could be bad, but you'll never solve the problem with a new sensor if you have a bad wire.

[Rock]

the new sensor comes with a new wire

[SoCal Driver]

Not from the connector to the DME.