low heat 2001 3.9
#1
02-01-2022 | 03:40 PM
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low heat 2001 3.9
Very low heat. All blower speeds work as they should. I can hear the blend door actuator moving and both heater hoses are around the same temp on my hand. I have not tried flushing the core yet and dread replacing it. don't drive this truck everyday so I have not paid very goo attention to where the needle on the gauge has been in the past. I am trying to figure out if I could be lucky enough to have an open thermostat instead of a core/ water pump problem.
The outside air was 28* this morning and after driving 15 miles the needle only went to the first white mark which is far short of even half way. I realize there are many variables involved in other trucks, but can anyone give me an idea where yours typically runs. 3.9 with 155k miles. Hate to start replacing a bunch of parts, but guess I will do the simple stuff first if I have to.
Thank you
The outside air was 28* this morning and after driving 15 miles the needle only went to the first white mark which is far short of even half way. I realize there are many variables involved in other trucks, but can anyone give me an idea where yours typically runs. 3.9 with 155k miles. Hate to start replacing a bunch of parts, but guess I will do the simple stuff first if I have to.
Thank you
#2
02-01-2022 | 03:54 PM
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Joined: Jul 2018
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From: oregon
#3
02-01-2022 | 03:56 PM
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From: Clayton MI
Temp gauges in these aren't the most accurate. Don't do what I did, and just assume the stat is bad.... plug in with a scanner, and see what PCM thinks engine temp is. The gauge on my 2500 doesn't get very high up the range either, I though it wasn't getting up to temp. After I changed the stat, and the needle went to the exact same spot.... I plugged in the scanner....... 195 degrees....
Ooops.
Ooops.
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V8Cowboy (02-02-2022)
#5
02-02-2022 | 06:42 PM
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From: S.W. Indiana
Very low heat. All blower speeds work as they should. I can hear the blend door actuator moving and both heater hoses are around the same temp on my hand. I have not tried flushing the core yet and dread replacing it. don't drive this truck everyday so I have not paid very goo attention to where the needle on the gauge has been in the past. I am trying to figure out if I could be lucky enough to have an open thermostat instead of a core/ water pump problem.
The outside air was 28* this morning and after driving 15 miles the needle only went to the first white mark which is far short of even half way. I realize there are many variables involved in other trucks, but can anyone give me an idea where yours typically runs. 3.9 with 155k miles. Hate to start replacing a bunch of parts, but guess I will do the simple stuff first if I have to.
Thank you
The outside air was 28* this morning and after driving 15 miles the needle only went to the first white mark which is far short of even half way. I realize there are many variables involved in other trucks, but can anyone give me an idea where yours typically runs. 3.9 with 155k miles. Hate to start replacing a bunch of parts, but guess I will do the simple stuff first if I have to.
Thank you
I would check for slop in the timing chain. I had a '94 with the 3.9 once. Heat sort of worked, but barely. The temperature gauge went half way from cold to center. The thermostat was the right temperature but the dealer service manager heard a lot of timing chain rattle. (I'm hard of hearing.) The chain had a lot of slop at 135,000 miles. I replaced the timing set and the heat would cook you afterward. My fuel economy also went up enough that I thought someone was messing with me. I went on a commute to work from 16-17 mpg to 20 and on long runs on the highway at 60, I got 24 a couple of times.