help? identify this connector

[c2kid]

aloha, i recently purchased a 91 c2 that had been stored for 2 years. after addressing most the issues (bad fuel, gummed up fuel pump, etc) i found a rodent nest in the left rear of the engine compartment. fortunately, not many wires were comprimised. i still have this connector not connected and i can't see where it might go. the car is having fuel delivery issues, even with a new fuel pump, dme relay, filter, and o2 sensor. anybody know where this hooks up to or what it is??
also, how can i test the crank sensor?? do i need an oscillascope?? help please. geoff

[c2kid]

i also should of said that's the left back of the engine bay on a tiptronic equipped car.

[LUFTMAN]

looks like the cruise control unit plug. a oscillascope is the best way to test the crank sensor . i have also used a fluke 88 multimeter and even a led light that baum tools sold many years ago for the 944 models it way a very low cost tool to see if you had a signal (light flashing ) when cranking engine but it did not tell you the strength (1.5 volt) of the signal. it was a quick test tool . tom

[lucittm]

To me it looks like the connector for the Bosch O2 sensor. Mine is a three-wire, and your connector has more than three wires but many of them may be used for other things. The schematic for your car shows a green w/black stripe wire, a brown wire, and a shield wire.

The crank sensor is amazingly reliable. It simply senses the steel bumps on the flywheel magnetically and then sends a pulse to the DME control unit on pins 47 and 48. I would pull the plug on the DME unit and check the pins with a digital meter. First for grounds and shorts and then when the engine is cranking over. You should see a few millivolts on the AC scale.

Good Luck,
Mark

[c2kid]

tom, i'm going to try the multimeter on the dme plug as mark suggests. i just don't have access to a oscillascope. i'd take it to a commercial shop but there isn't one on this side of the islsnd (only an independant 150 miles away). i'll try to find a cruise control unit in here, but perhaps it was removed by a previous owner. and mark, my o2 sensor is 3 wire, as i just replaced it. but the info on the dme plug is great. i'll try it tommorow.

[Superkrill]

[c2kid]

thanks superkrill, i know what it is now, but where does the other end of the plug it connects originate from? in your photo, the connector is unplugged. is this as it should be? thanks, geoff

[lucittm]

I see it now thanks to superkrill. I don't have cruise control, so this is news to me. So if you don't have cruise control, there is nothing to plug it into. Since it's pretty dirty inside, I would say it has never been plugged in.

Mark

[c2kid]

aha, i just figured that out myself. i thought to start at the throttle body as the unit shoulda been hooked to it. i found a disconnected bellcrank (with a hole for a cable) with a short linkage but no control unit. somebody musta pilfered it. cheers all, geoff