Engine Runs Hot 2002 Trailblazer

[MA Trailblazer]

I just pick up a new 2002 Trailblazer last month, and noticed it seems to run very hot. The gauge on the dash will run dead up at 210 once it warms up, even if it is a cool day. ( 50 outside )

 

My old 2001 blazer would only run near the 210 area on a VERY hot day, sitting in traffic, with the A/C on.

 

As today is one of the first hot days in my area, I noticed the temp gauage runs 2 lines ABOVE the 210 mark. When I hooked up my autotap to see if the gauge is correct, it shows the engine coolant temp at 217 when I am at idle with the A/C on. ( outside temp is 85 ) Once I get on the highway, autotap shows the temp will drop to 210. I thought I read that these motors have a very good cooling system, and a 190 thermostat, so I didn't expect it to run this hot.

 

Is this normal????

 

 

Another question is my truck will also shift VERY hard when the engine is cold and it shifts from first to second gear. After the truck runs for a few minutes, it will shift normal, and will only show up when its cold. Is this normal??

 

Aside from that I love this truck. It was built in april of 2002, so I hope they have worked most of the bugs out after 1 year of production.

 

JOhn

[inginear]

That's what mine runs too.  And it warms up faster than any car I've ever owned before!

[RyanbabZ71]

The cold shifting is normal.  The silverado trucks also do this and there was a TSB explaining why it is normal.  Something about saving wear on the trans until it warms up

[MA Trailblazer]

So your TB will run 2 lines ABOVE the 210 mark in 85 degree weather?

 

My 2001 blazer ran a #### of a lot cooler, NEVER going above the 210 mark.

 

One more question for you. Do our trucks come with a air filter for the HVAC. I know some of the new trucks and cars have them, but I can't find anything in the manual that says we have it.

 

Thanks.

 

John

 

2002 TB LTZ. All options except DVD and sunroof.  It has 3.73 posi gears.

[02EnvoySLT]

Mine run 210-217 also.  However, It seems to be the generals operating temp for their Aluminum based engines.  I'm not concerned as I have 0 knock retard at wide open throttle with 93 octane even in the heat and if the hotter running temps help the combustion process to get me the better fuel economy, so be it.

 

I do LOVE how fast this truck warms up in the winter!

[inginear]

Checked the water outlet temp with an infrared temp gun, it varied between 195-200 deg after a 20 mile drive.  I coud find some hot spots of 205-208 on the engine, excluding the exhaust mainfold.  The dash temp gage was a steady 210.  Not sure where the dash temp comes from, the computer, or a seperate sender.

[MA Trailblazer]

I just read a write up on the long term TB that Autoweek has in its fleet. They mention that the dealer had to reprogrammed a faulty cooling fan clutch. We do not have a electric cooling fan, so how do they reprogram it?

 

You can read the whole article a www.autoweek.com

 

John

[fawaz]

This is the post that will make everyone feel much better ;)

 

I just got my 2002 TB a week ago and I love it. And yes, it runs hot. It gets to 2 lines after 210 sometimes.

 

You might be wondering how is that post making everyone feel better? Well, I'm located in Saudi Arabia where the temperature is hitting 120 in here at around noon.

 

I was driving my TB today in 110F outside and the temperature of the car was 210 during my 4 hours drive

 

See? I told you that this post will make you feel better ;)

 

Fawaz.

[02EnvoySLT]

MA Trailblazer - The triplets us an Electro-Viscous (EV) cooling fan according to their tech briefs.

 

http://service.gm.com/techlink/html_en/pdf...7-en.pdf#page=8

[MA Trailblazer]

I have never heard of such a thing. Very interesting reading. Thanks for the article.

 

My truck still seems to run hot for me, but I have come to accept that it is normal. ( I guess it's old school that a motor should never run over 210 ) I did add a bottle of red line water wetter to it this weekend, which can't hurt things.

 

What a great website.

 

 

John

[inginear]

I just read a write up on the long term TB that Autoweek has in its fleet. They mention that the dealer had to reprogrammed a faulty cooling fan clutch. We do not have a electric cooling fan, so how do they reprogram it?

We don't have electric cooling fans, but the fan CLUTCH is electrically actuated.  If you want to check, look for the wire bundle running to the clutch

[DougS]

I got my TrailBlazer EXT about 2 weeks ago. I have been watching the temp. gauge and it does not go any higher than 1 mark BEFORE the 210. Even yesterday when it was 95 degrees outside and I had the AC running, still 1 mark before 210.

 

Doug.

[CMNTMXR81]

Two things;

 

1) GM runs all their engines as hot as possible for emissions purposes.  195+ degrees is the standard.

 

2) GM's gauges are far from certifiably accurate and they aren't calibrated per the individual lines on the temp gauge on your dash.  As such, your's may be showing 210 or more but in reality is running around 200-205.  The only accurate way is to read it with a scanner such as a TechII or AutoTap.  Or do the temp thing with an infra-red temp gun.

[MA Trailblazer]

I did check my engine temp with a autotap tool, so I know the gauge is dead on. ( what a surprise )

 

On the Trailblazer EXT the runs below 210, what engine is in it? The 4.2 or 5.3 ?

 

John

[DougS]

The Trailblazer EXT is the 4.2 I-6.