I have been working on this car for a few days now off and on. I have a problem that maybe someone in here might have been through already. What is the routing of the Dark Green wire that is suppose to come from the Temp Gage to the Coolant Temp Switch on the passenger side head behind the dip stick. Does it come from the ECM then to the gage then to the switch? Anyhow mine is lost and I cant find it. Any ideas/. Thanks in advance
Denny

that goes to the digital display.

what year?

Sorry its a 91 and dosent have dig. display

In this case, it's not the digital. I need to correct myself. I was in a rush when I posted that and I was wrong. Sorry for being misleading.

There are the two temp sensors. One on the manifold and one on the head.

The one on the manifold feeds the ECM. The other the analog temp display. Now, I don't remember, but do you have a button on your DIC called "Gages"? If so, you have a digital display. I am pretty sure 1990 didn't have it, but I thought 1991 did.

If you do have that, the digital display is from the ECM.

did this help?

No as a matter of fact it didnt, Seems like with all the Corvette people in this forum someone would know if the Temp Gage wire comes from the fuse panel to the gage and then to the sender? I relize it has 2 temp senders 1 for the ECM to record the temp for adjustment and 1 for the gage. This corvette is a 91 so there are stupid things changed during the 91-92 model years. Yes this does have half digital and half analog dash (which I stand corrected) by this I mean it has a Digital speedo and odometer, however the gages are analog. All I have is a Haynes book to go by. The Chevrolet dealership knows nothing about this year model and has no manuals because they are not a Corvette dealer. Sorry to be so short men but losing my patience with this dark green wire thing. Again anyone who has a factory manual for a 91 Vette if you could please look at the diagram and see where the Temp. Gage wire goes after it leaves the gage and the correct color would be very helpful. Sorry had to vent!

This wire goes to the gauge and the correct terminology is that it is a sending unit in the head, not a sensor. The sensor is elsewhere and it indeed gives it's info to the ECM and to the digital readout.
You might want to lighten up on folks who are trying to help you. We all have brain farts from time to time.

Quote:

hm. Yes, Notorious is right, you need to chill a little. I am not quite sure where you are getting your attitude from. I hope it's not directly from us, tho, but a perceptional issue with all forums. If that is the case, be nice enough to give us a chance to help, ok?

Oh, and how was I to know what you knew? We have to start somewhere, eh?

Let's step back a moment.

You have the hybrid digital/analog dash. It started in 1990 and ran through 1996, with some enhancements.

It still doesn't change the fact that the sensor is on the manifold and the one on the head is for the analog temp display on the right side of the IP.

I don't have a 1991 FSM, but I do have a 1992 FSM. I am willing to bet this circuit is identical.

8A-82-0. That's the page in book 2 that indicates the green wire goes straight to the IP. So no, there is no fuse panel interface. And for that matter, it makes little sense that the green wire WOULD have a fuse on it.

As for routing, IIRC, it goes down past the exhaust and then back up with the starter harness. It's been a while since I was in there, tho. It is close to the exhaust there, and could easily have burned. The later FSM's don't do a great job of showing routing. You can assume, tho... but you will really need the various component diagrams to make sense of it.

A little friendly advise, if you know something, elaborate in your question. It will increase the chances that you will get a full answer and not something you already know.

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Here it the schematic from the 1990 manual.

Exactly as bogus described from the 1992 manual, so you're pretty much sure the 1991 is the same. Even the same page!

You may want to try looking from underneath. The harness that runs over the bell housing from driver to passenger side, branches off and runs behind the passenger head, down to the starter. The temp gage wire runs in this harness. It runs up the block, between the exhaust manifold and block to the sender.

Remember that heat may have discolored the wire, but you're looking for a disconnected wire with a female spade lug connector, so any discoloration should not be an issue.

If it was disconnected, it may have fallen below the exhaust manifold and can't be seen from above.

OK Sorry for being an ass but I have been ran all over town on this issue and found out nothing. You guys are absolutly right! I put it up on the hoist last night to find a oil leak and what was staring me right in the face! Mr.Dark Green Wire with end all burnt off. The sad thing is just about all chevrolets I think have this wire running normally with the starter wires. I was just so sure it ran behind the dist. that it bit my butt. Now onto the next issue. Ya'll ever see a real bad oil leak from the end of the intake manifold? I have built tons of sbc and had my share of intake leaks but never fron the end. Motor looks super clean on the inside, compression is 175 to 180 and is suppose to have 200k on the motor. I just cant beleive there is any pressure under the intake to blow oil out. Has 2 pcv valves and are working good. Removed the oil pressure sensors,cleaned and retaped them and are dry when runningdist. base is dry also. But you can clearly see the oil coming out of the intake end seal. Is this common or should it dug into more.
Well sorry again for being so abrupt but the wire thing got the best of me!

Cool! Glad you found it.

As for the oil. For some stupid reason, these things blow oil out the chinese wall. I don't get it... but they do.

I use copper RTV and a drill to dimple both surfaces and have never had a problem.

two pcv valves?

no, one is a valve, the other a draw through.