[cardoc]

Getting hot then cooling down is generally a sign of low coolant. Look for a leak and you should go ahead and replace the thermostat. When the thermostats reach high temperatures several times, the performance suffers.

For future reference, the ECM will shut the AC off when engine temperature reaches 220 or higher. This serves two purposes, one to reduce engine load and two to help cool the radiator by stopping the flow of hot freon through the condenser which increases the cooling on the radiator.

 

[cardoc]

I hope you installed the wobbler on the up side when you put he thermostat in.

Sounds like you may have been low in coolant prior effecting the function of the ECT. The fans won't come on for high speed for cooling only until around 220. The ECT signal to the ECM controls when the fans change speed when the AC is off. The fans are high volume to start with, even on the low speed which should start up at 203.

If you have a scan tool you could watch the fan operation and speed in relation to what the ECT is sending. Of course, forcing it up past 210 will be a chore with a new Tstat and coolant.

 

[cardoc]

It wasn't the fans. That's how they are supposed to operate.

I try to use simple terms where I think it will help describe what I am talking about. Sometimes I forget and tend to confuse people. I'll see the look on their face and think to myself, "too technical".

The "wobbler" needs to be on the top to assist in bleeding air from the block side of the thermostat.

 

[cardoc]

The sensor is in the head behind he dipstick.

The fans will remain on if the temperature of the engine dictates a need regardless of the pedal position.

The AC shuts off with WOT which also shuts off the fans if the fans are only on for the AC operation.

 

[cardoc]

Sent PM

 

[cardoc]

That was an error in posting on my side I think. Somehow it got posted as a visitor message. I've talked to him since.

 

[cardoc]

Sub brought the car by this morning. I checked it. It has a seeping head gasket on bank one. When he got to the shop, it was about 3/4 gallons down. He said his wife mentioned it hadn't overheated all week.

Here's a video. The video was taken some time after the initial test, same result. Not only does it have a steady stream of bubbles after running and warmed up, but the computer is adjusting the fuel trim on bank one to positive. The burning coolant is increasing the oxygen reading from the AF bank 1, so the ECM adds fuel. The thermostat is working properly. The fans operate.

https://www.youtube.com/watch?v=khc2dWsZAjQ

 

[cardoc]

The engine is blowing the coolant out the exhaust. There is not an external leak and it is not boiling out the reservoir.

The coolant that is burning with the fuel mixture is increasing the O2 in the exhaust. That's why the ECM is adding fuel. It thinks Bank 1 is lean, when in fact it is water burning. We could also smell the coolant out the tailpipe. Its just not enough to cause a misfire. It apparently takes a few miles for the level to drop. His wife has been driving all week and lost the 3/4 gallon.

Yes on the funnel. I use it on everything that is coolant related when refilling to insure the air is burped out. It allows me to have coolant higher than the engine. It is also helpful in analyzing the coolant for HC's. I can put the 4 gas probe in the funnel and detect HC in the coolant.

I am going to swap his engine for the H6 I have in the shop. He is going to keep the engine out of the car with plans of tearing it down and overhauling with his son as a learning tool for both him and his kid.

 

[cardoc]

While I was looking at transmissions, I saw that an H6 from the boneyard with about 100K goes for 1200-2500 bucks.

The one I have in the shop was well maintained, full synthetic oil from the first 1k mile oil change and runs strong. Sub got a good deal. And its less than repairing the one in the car as well as quicker. I'll have it swapped inside 4.5 hours and that's with swapping his accessories.

 

[cardoc]

The engine is in. I've been running slow. Feeling crappie.

I took a video but its taking forever to upload. Just check my channel in probably 20-30 minutes. The Runt and I are delivering the car and his old engine, so we need to split.