Hi guys,

I don' t know really much about this engine, but is that normal the engine temp keep raising until the fan kicks in? The temp floats up and down, could it mantain a steady temperature when hot? When in highway the temp keeps steady at 180-190. When in traffic the temperature raises more and more until the engine stalls and it' s very difficult to start it again. Also I noticed, when hot, the oil pressure is under 40, while when cold is near to 60. Is that related to engine temperature?

Any help is really appreciated!

Emiliano

 

When driving it's easier to maintain a constant engine temp. In traffic, you have no air movement so your temp is going to go up until the fans come on and cool it back down. So yes you will see your temp fluctuate like that. The stock setting for the fans to kick on was very high, like 237 degrees or something. When I had mine, I wired in a separate toggle switch for those situations, so I could manually turn the fans on and keep from getting so hot.
Now if your engine is stalling once it's hot, that's an issue.

Oil pressure being higher when cold is normal due to the oil being thicker. As the engine warms up (the oil will warm up too), it will thin out causing the pressure to decrease.

 

What is the temp on your gauge when the car stalls, you may be having the computer go into "limp home" mode. This should not cause a stall but it may as this mode just sucks all power from the engine, it feels like you are running on 2 cylinders.
As the OP said you can bypass the thermal switch that waits for it to heat up before they kick the fans on. My car, one of the previous owners just grounded the green and black wire from the fan relay and when you turn my car on both fans just come on and stay on. this will cause the car to take longer to heat up but I notice I only fluctuation between 190-220 and 220 is only when the A/C is on and at a light. I also drive in 95 degree temps here in sunny SoFlo. Also make sure you have fresh coolant, green should be changed once a year.

 

Ok, thank you for the infos! About the stall, maybe the injectors suffering heat? I read many times in this forum that the stock Multecs (which are in my engine) can short and cause random stalls. Can it be related somehow?

 

Thanks Vinny, I’ ll keep in mind this! But first I want to try another thermostat valve, it seems I’ ve a 2.8 head mounted on a 3.1 engine...

 

Ahhh the trusty 3.1. My experience is they like to run hot and they cool off almost instantly with it being so small. And it's totally normal for the temps to go up and down constantly. I wouldn't worry about it. I have a toggle hooked up to my fan but rarely use it anymore. Fans on the 3.1 turn on really high like my man said. As soon as my fan comes on my temps drops like a domino. Just make sure your fan is in tip top shape or it could cost you your engine. As for your car dying on you when hot, most likely gonna be your icm. They crap out every once in a while. They don't like heat. Once they cool it will start again.

 

I replaced a remanufactured distributor with a new ICM from Cardone, bought on Rockauto. Maybe it was faulty from the beginning?

 

Did it start acting like this right after? Or a while after you put it in there?
when I replaced mine there was no grease under it. I put the stuff for computer fans under the new one and my heat soak like issues went away and mine never over heat and I live in Vegas.

 

I think I never put grease on it, infact I' ve the same problem. I don' t even remember if it there was in the box, long time ago. Where exactly do I have to put the grease on ICM? Around its "body", or connectors zone?

 

All of the 2.8 heads (85 and later), 3.1 and 3.4 heads are identical. Casting, valve size, CC, etc. Everything is the same.

 

Good to know, thanks! Meanwhile I'm replacing the ICM. The new one should arrive tomorrow. Let' s cross fingers!

 

The car runs like new at cold, when it gets warm stumbles and stalls. The ICM is the easier thing to fix, if I keep to have this issue I' ll change injectors for sure... Now that I took off the old ICM I found some grease on it, I don' t know if it' s a good or bad sign...

 

Great news! I replaced the ICM and now the car runs much much better! Every time I was in stuck in traffic it never set the code 54 anymore, and the temperature is in range without overheating. It still misses at high temp, I think it’s time to replace injectiors too...