faulty thermostat causing CEL to go on???

[Droopynut]

Since I've been driving my 62, I've noticed that the temp gauge will not move too much even after 20 miles of driving. Sometimes it warms up and the gauge reads in the middle (normal), sometimes it won't. I don't think it's a gauge problem.

Plus, after about 15 or 20 miles of driving the CHECK ENGINE LIGHT goes on. If I shut the truck down and wait a minute...start it back up, the light is off.

My theory is the thermostat is mainly stuck open not letting the engine warm up enough causing the light to go on. Then if I'm lucky it will close up a bit and let the engine warm up enough to keep the light off after restart.

What do you think?

 

[Wile E Coyote]

I'm thinking, no. You've got seperate issues. 'Sometimes it warms up....sometimes it doesn't', does not exclude a gauge problem. An intermittent grounding of the sensor or related wiring could easily make a gauge funky.
As far as the CEL, don't guess, and just check the codes yourself. I'm gonna venture a guess the codes you'll get regard the O2 sensor(s).

 

[cruiser88]

Yep... check for codes and buy a real temp,oil,volt cluster gauges

 

[Landpimp]

pretty sure the T-stats stick closed when bad and make it overheat fast, but you can take it out and test it to be sure

and it doesnt sound like its related

 

[Droopynut]

what kind of gauges would you recommend?

I like VDO. Will they work?

 

[Droopynut]

Can you help identify these, what appear to be sensors?

What is 1, 2, and 3?

 

[Droopynut]

I may have found the problem... the reason why my CEL comes on might have something to do with this.

The EGR VSV is broken... the vacuum connection at least. I need a new one.