How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Gary Your Own Question
Gary, ASE Certified Technician
Category: Chevy
Satisfied Customers: 916
Experience:  Senior Technician
Type Your Chevy Question Here...
Gary is online now
A new question is answered every 9 seconds

Had 1985 iroz rebuilt over the winter by a licensed mechanic

Customer Question

Had 1985 iroz rebuilt over the winter by a licensed mechanic runs great but have temp gage issues gage reads hot not in red but close. I took it back has a new sending unit and I supplied them with a new oem temp gage. His computer reading off the car reads not hot. What else should we look for?
Submitted: 1 year ago.
Category: Chevy
Expert:  Gary replied 1 year ago.

Hi there,

I would take the sender wire off. With a warmed engine running, the gauge should read under cold on the lower stop.

Can you try this please?

If the gauge reads anything above cold, you have a partial to ground on the sender wire or the cluster voltage regulator is faulty.


Customer: replied 1 year ago.
Just had the cluster calibrated by specmo in flint Michigan during rebuild we have eliminated a bad wire I will let you know
Expert:  Gary replied 1 year ago.

That is odd, you have done all that work, and it still reads high.

Is the temp sender near the coolant temp sensor for the Engine ECM?

What temperature does the ECM read in data?


Customer: replied 1 year ago.
Data off computer reads fine. I don't know I'll let him do some more we know the wire is good I'll be in touch
Customer: replied 1 year ago.
Voltage regulator all other gauges seem to work
Customer: replied 1 year ago.
Sending unit is in original spot from factory
Customer: replied 1 year ago.
Where is the regulator located? In the cluster or underror the dash?
Expert:  Gary replied 1 year ago.

The voltage regulator would be in the cluster.

Is the sender definitely the correct one for this engine?


Customer: replied 1 year ago.
I did install it could be from parts store. Where as I know the gauge I gave him was a Delco oem replacement. He said he tried more then one just in case we had a bad sending unit. The gauge didn't seem to work right before I had it rebuilt. When the engine got close to red line I shut it down the thing is the electric fan wasn't running so also thought that was an issue but he said fan is turning on properly. When it cooled do I got it on open road gauge read 220 should be right. The next day I took it to the mechanic as I drove there is could see my gauge coming up as it got past 220 I saw the thermostat open and watch the gauge drop so the gauge does work but seems like after the engine is hot the gauge is inaccurate. I don't get it.
Customer: replied 1 year ago.
I didn't install it
Expert:  Gary replied 1 year ago.

Is this a thermostat issue, rather than a gauge issue?

I've always been suspect of some thermostat brands.

Or a partly blocked radiator?

Customer: replied 1 year ago.
Radiator looks good and as I watched the the gauge drop in temp I know the thermostat is opening. I'll be in contact I'm still thinking and so is he. I will let you what we found thanks
Expert:  Gary replied 1 year ago.

Ok, I'll be here for you.


Expert:  Gary replied 1 year ago.

Hi again,

Have you had any progress with your engine problem?

I hope my advice has been of assistance to you.

Please rate my service at your earliest convenience.

Kind regards


Customer: replied 12 months ago.
Not sure just got the car back. I'll let you know
Expert:  Gary replied 12 months ago.

Ok, hope all is fine now.


Related Chevy Questions