I have a 1987 corvette and cant identify the sensor that is to the left of the coolant temp sensor here in the photo. This is located in the front of the Intake Manifold. Can anyone help?

 

 

Cold start!!!!

 

 

I've been told there are 2 sensors for coolant temp, one reports to the ecm and the other is for the dash gauge. Don't take my word for it, I'm sure someone with better knowledge will come along soon.

 

Hello CorvetteRules,
You are correct on the two temperature sensors for the coolant. One is for the gauge and the other is for the ECM. I have an 1988 C4 like that. The second sensor is a one wire sensor mounted in between cylinders #1 and #3 and has a green wire going to it.

 

Thanks for the drawing. Thermo time switch sounds good to me. I finally got the coolant switches figured out. The one for the Aux fan is between plugs 1 and 2.
the sender for the dash is between plugs 6 and eight. Never did find the primary fan switch. It must be only controlled by the ECM I'm guessing!

 

Just to clear up something here, the spark plug #1 is on the drivers side nearest the front of the engine. Cylinders 1,3,5 and 7 are on the drivers side, 2,4,6 and 8 are on the passenger side of the engine.

You are correct in assuming that the fans are indeed controlled by the ECM via a relay. When an ECM fails (dead) the cooling fans all come on when the key is turned to run.

By the way, Welcome to the Corvette Forum! This is the place to be if you have a Corvette!

Besides having the set of Factory Service manuals you might like the book I use frequently for questions. Corvette, Fuel Injection and Electronic Engine Management 1982-2001 by Charles Probst and printed by Bentley Publishers. This book is a "must-have" if you work on the fuel injection systems and/or the engine management systems as it explains the operation and how it all works together. A very handy book to have in addition to the FSM set if you own and work on a C4 Corvette.

Good Luck and enjoy your Corvette!

 

Thanks for the info and warm welcome ctmccloskey. All I have now is the Haynes Repair Manual. I recently received this C4 from my son as a retirement gift.
So now its a new hobby for me. I'll look into the book you described. I'm sure I'll have lots of more question on this forum.

 

Hello again turkeytrotter!

The first book you should invest in would be the Factory Service Manual set for your particular year Corvette. They are available in print or on DVD. The last time I bought a set for my 1988 C4 they were close to $80 for the FSM set of two books. The book I mentioned above is a awesome resource but not the first book you should get. The FSM's are priceless when working on your C4, they have all the trouble shooting guides and even the schematics for all the systems in the car. The second tool you will need is a good quality Digital Volt Ohm Meter as there are a lot of places where you need to have one. I have two Fluke Meters and they are very useful. If you have a scanner or some way to read the codes on your Corvette you will find it very handy, lots of opinions here. Another valuable tool is a Fuel Pressure Gauge which allows you to verify that you have the correct fuel pressure for your car, I bought one with a long hose so I can tape the gauge to the windshield allowing me to monitor while driving temporarily.

That is a very nice Son you have there! My son keeps expecting me to buy him cars...

My wife and I bought our first Corvette back in 1991 and it was a 1968 L-71 Convertible with a four speed stuck in a barn. It has been my toy for a long time and in that time I rebuilt the 427 to make even more ridiculous horsepower. When we started having kids my son's car-seat was mounted in the 1968 Corvette and we bought a 1988 C4 Coupe for my wife. Corvettes are a great hobby and a lot of fun as well. There are a lot of Corvette clubs all over this country and they can be a huge help to a Corvette newbie. There are NCRS Corvette Clubs for the folks who want to "restore" their Corvettes and generic Corvette Clubs sponsored by Chevrolet dealers. I was part of a dealer sponsored club for a while and it was fun and very educational (before the internet).

Depending on where you live there are Corvette events that happen annually like "Bloomington" or "Corvettes@Carlisle" (in PA) and many others. My family and I have been going to Carlisle for the annual Corvette show the third weekend of August every year for a long time now. I used to meet my cousin from New Jersey up there and both of us went to the Corvette show for three straight days. If you have not been to one of these events please try and take your shopping list with you. I have saved thousands of dollars at Carlisle buying parts for my two Corvettes. Where else can you mingle with 50,000 other Corvette nuts? I had friends that drove up from the Keys every year in a 1958 Corvette Convertible and spent a week up here.

There are no dumb questions here... ask away and "somebody" will have an answer. I hope that you have the "Time of your Life" with your "new to you" Corvette!
Good Luck