Temperature Gauge fix for '99 & up?
Thread Starter
Teching In
Joined: Aug 2003
Posts: 42
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From: Cleveland, OH
Temperature Gauge fix for '99 & up? I want my temperature gauge (idiot gauge) fixed!!
I assume most of you know in '99 and up, the coolant temperature gauge is deliberately programmed by GM to be an "idiot gauge". It ALWAYS reads around 200°F after warmup, provided the actual temperature falls within some predefined range.
This was a programming change that was made in firmware to address the problem of idiotic people going to the dealer and complaining about temperature gauge fluctuations. The fluctuations they were seeing were actually the normal changes due to the thermostat cycling open and closed.
I sent an e-Mail to Ken Kelly of LS1-Edit, wondering if there is something in the PCM that they might consider addressing in there product. Here are his replies over 2 days:
"I have heard of this before. I will have to search the code, and see if I can figure out where the Gauge is driven. It is not in LS1-Edit now. ... I spent a little time last night looking at the PCM, and don't see it. I think it may be in the dash computer."
So if what he "thinks may" be the case, the "problem" must be in a firmware chip in the dash gauge cluster/panel. Therefore, I thought a simple solution MIGHT be to simply change the dash gauge panel with a 1998 model year. But I just found out that the '98 is different (connector, etc.). Bummer?
Any other ideas? Worst case, I will most likely add a real gauge (pillar, etc.?) someday (soon?), but it would be a real shame, almost laughable, to have a factory temperature gauge in the dash, and an aftermarket gauge as well.
Any help would be greatly appreciated!
I assume most of you know in '99 and up, the coolant temperature gauge is deliberately programmed by GM to be an "idiot gauge". It ALWAYS reads around 200°F after warmup, provided the actual temperature falls within some predefined range.
This was a programming change that was made in firmware to address the problem of idiotic people going to the dealer and complaining about temperature gauge fluctuations. The fluctuations they were seeing were actually the normal changes due to the thermostat cycling open and closed.
I sent an e-Mail to Ken Kelly of LS1-Edit, wondering if there is something in the PCM that they might consider addressing in there product. Here are his replies over 2 days:
"I have heard of this before. I will have to search the code, and see if I can figure out where the Gauge is driven. It is not in LS1-Edit now. ... I spent a little time last night looking at the PCM, and don't see it. I think it may be in the dash computer."
So if what he "thinks may" be the case, the "problem" must be in a firmware chip in the dash gauge cluster/panel. Therefore, I thought a simple solution MIGHT be to simply change the dash gauge panel with a 1998 model year. But I just found out that the '98 is different (connector, etc.). Bummer?
Any other ideas? Worst case, I will most likely add a real gauge (pillar, etc.?) someday (soon?), but it would be a real shame, almost laughable, to have a factory temperature gauge in the dash, and an aftermarket gauge as well.
Any help would be greatly appreciated!
Re: Temperature Gauge fix for '99 & up? to fix, ... now get ready..
You have to get a 3 wire sensor, run an extra wire to your dash cluster, install a 98 cluster, drop your tank and install the old style 98 fuel level sender, and.... install a 98 PCM.
tada!!!!
OR.. just get an aftermarket coolant temp gauge and use a 3 wire sensor, 1 for the signal. (each signal is different format btw).
You have to get a 3 wire sensor, run an extra wire to your dash cluster, install a 98 cluster, drop your tank and install the old style 98 fuel level sender, and.... install a 98 PCM.
tada!!!!
OR.. just get an aftermarket coolant temp gauge and use a 3 wire sensor, 1 for the signal. (each signal is different format btw).
Re: Temperature Gauge fix for '99 & up? Yeah that temp gauge is a major painus in the anus . . . There was also another thread on this board a while back where we discussed the problem in detail. It's possible to fix the stock gage, but it would be a lot of work unless we get a hold of a firmware fix. I'll be using a Palm hand held running Autotap to monitor ECT while I race at the Salt Flats next month.
