Ronald Crall

Purchased a 92 new and sold it 5 years later. Missed it so finally found a rough 93 that I will turn into a nice driver. After solving a variety of problems (opti-spark, ignition module, water pump, blown head gaskets and warped heads) it is running. The temp gauge is not working (probably partially to blame for the warped heads). I understand that the temp sensor is between plug 7 and 8 and connects to a dark green wire. I cannot find the wire, and presume that pulling the instrument cluster will provide little assistance in tracing it. Can someone with a 93 pop their hood and tell me where the wire enters a harness? If I can find one end I should be able to inject a tone and trace it. Afraid to drive the car given it's recent history without knowing the coolant temperature.

antfarmer2

Analog is not much good use your digital. Does it work?

PatternDayTrader

I thought it is routed from the harness breakout by the starter solenoid up through, and between the manifold and the head; to the sensor.

Someone will jump in on this and confirm with 100% certainty.

Ronald Crall

Still sorting the digital out

antfarmer2

On my 94 you just push the gauges button till it comes up. The sensor is on the water pump I would go after it first. Analogs lie and most time to hot can drive you nuts.

Just looked at my 94 and the green wire disappears going down towards the starter.

Ronald Crall

There is a 2 wire sensor between #1 and #3 plugs with nothing plugged in, and a 2 wire plug near the ASR box that would reach but would not fit. All of the EGR stuff removed. Is that sensor and plug likely part of the EGR system?

WVZR-1

Does your 2 - pin sender/switch look like this? And maybe/likely the cylinder heads aren't OE to the '93 Corvette?

Ronald Crall

I have little knowledge of the car so they may not be original, however it is a two pin, not a pin and blade connector. Car purchased inoperative, optispark and water pump bad, however my 92 ate a couple of those in less than 100k miles and this showed 120k so no surprise. After replacement I discovered that the head gaskets were blown so I found a pair of 94 Firebird LT1 heads with correct part numbers for a Vette so I had them pressure tested and resurfaced and replaced the originalls. The 6-8 port was plugged and the 1-3 sensor removed so I took the 1-3 sensor from the old heads and put back into the replacement heads.

Thanks to everybody's responses last night I found the analog temp gauge wire tangled/fryed in the headers. Had trouble getting the plug out of the 6-8 sender hole so removed the 1-3 sender and installed a new analog temp sender on the left front and spliced a new wire to complete the circuit. The gauge now works correctly, many thanks for the help.

Now I have to figure out the digital gauges. The speed/fuel part of the display works nearly all of the time, the left upper quadrant less than half the time, and the segment below the line somewhere in between. The control buttons may work occasionally, else the display changes by itself more often than it looks like. Following that, the climate control unit appears totally dead, however; with a working temperature gauge I can at least start driving the car to see what else needs work.

WVZR-1

Your heads being from a later F-body is the reason for the sender location. What you've done is what I was going to suggest and I was going to provide a part # for the appropriate connector for you. Seems you've already accomplished that. I was going to suggest maybe picking the DK GREEN from the C100 mating connector at the dash/firewall rather than trying to find it in or about the conduit that was originally routed along with the KS wire, O2 etc in the starter vicinity.

BTW - that sender is a single wire "functional" device. It uses 1 pin for function and the second for indexing. A connector would have had you working.

Ronald Crall

Thanks for the information. Where is the "C100 mating connector". I didn't bother to put a tone on the wire and trace it back, probably should have but i was too anxious to see if problem solved. I would have preferred to find a better route than down by the headers collector.

WVZR-1

C100 is behind the battery at the firewall/dash. Do you have the FSM?

Ronald Crall

Just got a copy on CD as well as a Chiltons manual

WVZR-1

That's sufficient but here is the C100 information for a '93. Everything is on your CD and it should be searchable. C2 of ENG SIDE @ C100 is TEMP GAUGE.

Ronald Crall

My CD has PDF's that are not searchable. Looks like a knock off of a real CD. Valuable info but hard to find.

Thanks for the information. If I am reading correctly C2 on the engine side is the Dark Green I need to use. Too bad only noted as "instrument cluster" and not "analog temp gauge"

Any suggestions on where to start looking for the issues with the Digital gauges?

Cliff Harris

There are two ways to do an FSM CD. One is to just scan all the pages and put them on the CD. The problem with that is that they are just pictures of the FSM pages and NOT searchable. The other way is to have text on the CD. I don't know how they do that. Maybe OCR.

Anyhow, the Bishko CDs are the searchable ones.