Temp gauge inop

[John Boothby]

The short story: Removed plenum to fix secondary vac leak (check valve). Short drive to check that everything was functioning properly, they were. Put charge on battery, now the temp gauge doesn't work. Stays on cold, does not move. Please tell me that I do not have to remove the plenum again, as this will be the third time in as many weeks! I do not believe that the sensor connection at the back of the ignition module is loose, but it could be. All the other gauges work properly. What now!!

Get ready Jerry, I may be buying yet another set of gaskets!!

Check and see if you are getting a coolant read out on the ac unit.

You probably had the connector slip off or did not plug it back in. Your gaskets should be fine when you separate the plenum. Just go slow.

[John Boothby]

Hi Jeff. The a/c readout shows a preselected cabin temp and an ambient temp. Is this what you are talking about?

Hold the fan speed up and down buttons down for 5-7 seconds. You will enter the diagnostic mode. Press fan speed up to -16- and press the fan speed auto button. It will display the coolant temp in Celsius.

[John Boothby]

Thanks Jeff, I had forgotten about that little diagostic aspect of the a/c system. I just checked it and it read 53 degrees c.

[John Boothby]

I started the car up this morning with the coolant temp on the a/c turned on and the temp rose as the car warmed up. So I am guessing that the connection under the plenum is ok. So now it looks like the gauge is bad. Does this mean I need an entire gauge cluster? Other options? Fuse? I have been scanning the service manuals with no results.

Originally Posted by John Boothby

I started the car up this morning with the coolant temp on the a/c turned on and the temp rose as the car warmed up. So I am guessing that the connection under the plenum is ok. So now it looks like the gauge is bad. Does this mean I need an entire gauge cluster? Other options? Fuse? I have been scanning the service manuals with no results.

Just keep driving it until it goes tits up again. It's hard to shoot a intermittent problem. I doubt the cluster has gone bad, and it might just be the sensor.

[John Boothby]

I just could not stand driving around looking at an inop temp gauge, so I pulled the plenum, again. Sure enough, the temp sending unit had become disconnected. I reconnected it, put it all back together and everything works fine now. For those that don't know, there are two sending units, one above another. The lower one is the temp gauge. It has a slip type clip connector. This can come off easily. The top sending unit must be for the electronic temp monitoring because it has a more substantial plug-in connector.

I have now R&R'd the plenum 4 times in the last 6 months. So, if anyone in the Vegas area needs help with a plenum pull, I'll be more than happy to help. I feel like I can do it in my sleep!

[secondchance]

Originally Posted by John Boothby

I just could not stand driving around looking at an inop temp gauge, so I pulled the plenum, again. Sure enough, the temp sending unit had become disconnected. I reconnected it, put it all back together and everything works fine now. For those that don't know, there are two sending units, one above another. The lower one is the temp gauge. It has a slip type clip connector. This can come off easily. The top sending unit must be for the electronic temp monitoring because it has a more substantial plug-in connector.

I have now R&R'd the plenum 4 times in the last 6 months. So, if anyone in the Vegas area needs help with a plenum pull, I'll be more than happy to help. I feel like I can do it in my sleep!

Eventually dreaded plenum pull becomes nothing, don't it?
Anyone fabricate plenum bolts w/ wing nut?

[tomtom72]

Originally Posted by secondchance

Eventually dreaded plenum pull becomes nothing, don't it?
Anyone fabricate plenum bolts w/ wing nut?

I was wanting something like velcro or maybe something like those old twist lock hood pins that my Mach1 had......