2001 Monte Carlo LS with 3400 V6, no mods, 114k miles.

I'm driving to work the other day, the temp gauge drops out completely. About ten minutes later it kicks back on. When this happens the air condition compressor cuts out (still blowing, but blowing lukewarm air).
The drive home, same thing happens (wasn't running a/c at the time tho.).
Next day, same issue but took the temp gauge a little longer to kick back in.
Yesterday, the temp gauge drops out, never kicks back on on the ride in. Halfway through the drive home the check engine light comes on also.

Anyone have any ideas what it could be?


Also, I'm in Philadelphia. Any local people know of a good shop that is familiar with this gen monte carlos?
I finally finished paying off the loan this month and it's time for a tune up (i'm still running on the orig plugs and fuel filters), and kinda want to put a few performance mods on it (cai, better brakes, get rid of u-bend, better t-stat, etc.). I'm not really that familiar with anything under the hood. I did a full brake job on my last car ('93 buick regal 3.8L) but that's the extent of my wrenching experience.

Finally, has anyone with the same model engine had to replace the ignition coils? They died on my buick at 140k, and it was an expensive job. I want to have an emergency savings fund if that is going to be happening this year on the monte.


Any help is greatly appreciated.

-Riggs.

 

(crickets)

Hello? Anybody?


Oh well, when i started it up monday morning for work, everything was normal again. She's about to go in for a broken mirror fix (somebody smashed it while i was parked....the mirror was on the sidewalk side in a foreign neighborhood) and a tune up this week, so I guess I'll have them check the codes.

 

I just had the same thing happen today. When I went to work the A/C worked fine, parked the car , came out after work - nothing. Neither my A/C or temp gauge worked. A/C was only blowing hot, when I turned off car & restarted it, all of the gauges "reset" themselves except for the temp gauge - it barely moved.

Anyone have any ideas?

 

are your radiator fans running constantly and after you shut the car off do they stay on? if so i would say ur tstat...it already sounds like a tstat but that would b a clue

 

Yes, the fans were running for a while after the car was shut off (at least when the temp gauge was not working.)

Dropped it off at a local chevy dealer this morning.

Engine was throwing codes for t-stat running too cool and also codes for misfiring in the engine.

I bought the car used with 28k 2 years ago (its a 2001 LS). It's up to 114k now. Never had the coolant flushed or anything. In february it was leaking coolant onto the engine block. I took it in to a local garage and they replaced the lower intake gasket.

Turns out he topped up the dex-cool with green coolant without flushing the rad after doing the intake work.

The first estimate that I got this morning was a little over 800 for a leaking intake gasket and a new t-stat. When they pulled the intake manifold off, they discovered that the manifold itself is cracked. Now I'm up to about 1200 in work for that.

Whew, hopefully this is the last problem for a while, as it's getting to expensive to keep.

Getting new plugs, wires, and fuel filters while they're in there. Coolant flush too (although since it's GM, they insist on using dex-cool again). Oh, and of course and oil change since the intake was leaking water into the oil.

Now I'm up to about 1500 in work.

Whew, I'm gonna be working overtime this week.

-Riggs.



Can anyone explain why the a/c would stop working with a t-stat issue? Are they actually related?

Also, anyone in the philadelphia are recommend a local mechanic that's reliable and familiar with the monte carlos?

-Riggs.

 

Ok, my CEL came onand the code stated that the t-stat was running cool, and the suggestion was to install the 192/195 t-stat rather than the 180 t-stat that I was running. Well, after installing the hotter t-stat the temp guage started working again and the A/C came back to life. I was told that the colder t-stat was making the computer think that the car was constantly in "start-up" mode and it wouldn't run right and the gas mileage would suffer, which I had been noticing. So far, so good on everything else though. My gaskets are still doing fine, no leakung outside or inside as far as I can tell. I hope that was all that was wrong, guess we'll see what happens.

 

I'm pretty sure that the temp gauge issue and the intake were completely unrelated. Unless, of course the dex cool/green antifreeze mixing caused the manifold to break. The gunking up was what caused the thermostat to die though. It stuck open, causing the engine to run cool.

I get my car back tomorrow. Can't wait.