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Engine Hot AC Off

3951 Views 9 Replies 4 Participants Last post by  PGA2B
Was driving to work today and got Engine Hot AC Off message and gauge was all the way on the low side. Lucky I wasn't far from home so I took her home and drove the DD to work.

Checked under the hood and nothing was overheating or hot and fluid was normal level.

I was logging with HP Tuners and temp was normal.

Turned off the car when I got home and when I went to restart all gauges did the normal sweep EXCEPT the Temp gauge and it didn't move.

I didn't get a chance to check for codes.

If the Temp Sensor was bad how would I still get a reading from HP Tuners and would a bad sensor cause the gauge not to do the startup sweep?
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Was driving to work today and got Engine Hot AC Off message and gauge was all the way on the low side. Lucky I wasn't far from home so I took her home and drove the DD to work.

Checked under the hood and nothing was overheating or hot and fluid was normal level.

I was logging with HP Tuners and temp was normal.

Turned off the car when I got home and when I went to restart all gauges did the normal sweep EXCEPT the Temp gauge and it didn't move.

I didn't get a chance to check for codes.

If the Temp Sensor was bad how would I still get a reading from HP Tuners and would a bad sensor cause the gauge not to do the startup sweep?
I read that the sensor in these cars goes out quite often , Swap it out it’s like 30 bucks & a 19 mm socket with a swivel
Got one coming. WIll be here Saturday.

It did set a P0128 code. Cleared it and it has been fine since. Did a quick drive and gauge worked fine and no codes...
Been there done that. ECT sensor.
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Been there done that. ECT sensor.
Yeah that is why I ordered one. I saw your post.
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Well, Got the code again this morning. I replaced the sensor a month ago and no issues until this morning. The ambient temp was 52* and HP Tuners shows the ECT in the normal range.

I do have a 160* T-Stat. So I just unchecked the SES box and set P0177 & P0128 to no report.

Also made a tune revision as I was a little lean around 9K Hz.

Flashed tune, cleared code and went for a spin.

All good and will log on the way to work in the AM to check the new tune.
Well, Got the code again this morning. I replaced the sensor a month ago and no issues until this morning. The ambient temp was 52* and HP Tuners shows the ECT in the normal range.

I do have a 160* T-Stat. So I just unchecked the SES box and set P0177 & P0128 to no report.

Also made a tune revision as I was a little lean around 9K Hz.

Flashed tune, cleared code and went for a spin.

All good and will log on the way to work in the AM to check the new tune.
Did this code ever come back since you flashed the tube and cleared the code just replaced the sensor and the wire harness to the sensor due to damaged wires and was on the way home and engine hot ac off came back on but I don’t have hp tuners and car is bone stock
Did this code ever come back since you flashed the tube and cleared the code just replaced the sensor and the wire harness to the sensor due to damaged wires and was on the way home and engine hot ac off came back on but I don’t have hp tuners and car is bone stock
No, I turned it off so it would not come back.
No, I turned it off so it would not come back.
Ok thank you I appreciate it gonna look into getting an hp tuner or see if somebody I know has one that can hook me up with it for a day
If they have one they will have one you will need to license your car and it cost $100 as it will take 2 credits and they are $49.99 each. Or you can get your own.
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