My Overheating Issues

Well I'm taking the Intrige back to the dealer to try and figure this out again. I will take it in the morning. I will let you know.

Congrats Rolm on fixing yours. I wondered if that may be my problem but my belt is fairly new. Oh well, we shall see.

Good luck guy I could not figure out why I was having over heating. I just stumbled on the solution. The local parts store had a sale on belts so I figure why not change mine it was in there since new and that fixed the over-heating

Just an update, they are currently still looking at it. I keep getting the answer "Its not uncommon for it to run around the 3/4 mark in this weather" Its currently hotter than normal hear in KY. Its around 100 degrees.

I don't buy that answer. Oh well, I forsee a 70-90 buck charge to tell me nothing is wrong. I know something is though. Maybe I will change the belt just fo rthe heck of it when I get it back. Maybe I will get lucky.

I will keep everyone posted.

3/4 temp definitely means that something is wrong. In Pittsburgh, we've been seeing weather in the upper 90s, even over 100 in a few areas. I've also been in a lot of standstill traffic during this weather. The highest I've seen my temp gauge go is exactly to 1/2. In fact, for the most part while I'm idling in traffic, that's where it stays. When I'm moving 30+mph, even in the hot weather, it stays exactly half way between the 1/4 and 1/2 lines.

Have you checked to see if your cooling fans are coming on? How about your transmission? Any problems there? Also, how old is your coolant? Dexcool?

New update. They just called to say they cannot find anything worng with the car. Everything checks out ok.

Here is the kicker though. The mechanic says that 3/4 on the temp gauge is not overheating for this car. As long as it does not hit the "H" its not overheating. I don't buy that.

Funny I have had the car for 3 years now and never had the gauge go above half and now for the past year winter and summer it will climb. It was hitting the "H" back in the winter months.

Oh well, fans are all working properly. Coolant was flushed back in the winter. I have put to T-stats on it. Nothing works.

Nothing makes since what so ever. Car runs great.

Guess I will will try a new belt and see if that fixes mine like it did the other guys. If it does, I will let you know, and I will personally make a trip to see that mechanic and let him know. Otherwise, I will drive it until it blows up.

Hmm try thinking about it from another angle: Have they checked to see if the coolant temperature sensor is misreading temperature, making gauge read incorrectly?

Also have you checked inside the bumper/rad area for plastic bags or roadkill blocking airflow?

I know what you are going through, I went through the same. As a last step I was going to go to the local bone yard and find a larger rad, as I said I stumbled on the solution with the belt. The after market temp gauges are cheap even Walmart sells them and they are very accurate, why not try one very easy to install, Give that a try just to put your mine at easy. Keeps us updated. As a last suggestion I wonder if the fins in the water pump dis-solve that way they did in the BMW 3 series cars.

You might want to try running premium gas since the Intrigue retards the timing to use regular. Retarding the timing means more heat if I remember correctly.......alway, just a possibility.

Was driving my intrigue a few days ago at 75mph when outside temp was 101F. A/C was on. Notice that the temp gauge move up to touch the bottom of the 1/2 line. Slowed down to 65 mph and it dropped a tad but was still running hotter than normal. Maybe its time for a new belt??

You might want to try running premium gas since the Intrigue retards the timing to use regular. Retarding the timing means more heat if I remember correctly.......alway, just a possibility.

Prove it, I want logs from scantools showing the differences. Until then, I call complete bullshit on that statement, pardon my french.

Im not sure about timing causing heat, but I wholeheartedly disagree that it retards timing.

LittleHoov, since you know so much about the intrigue 3.5 engine, perhaps you you care to state whether the following information applies to the LX5 engine:

Octane Description
Octane is a measure of a fuel's ability to resist spark knock. Spark knock occurs in the combustion chamber just after the spark plug fires, when the air/fuel mixture in the cylinder does not completely burn. The remaining mixture spontaneously combusts due to temperature and pressure. This secondary explosion causes a vibration that is heard as a knock (ping). Fuel with a high octane number has a greater resistance to spark knock. This vehicle requires 91 octane ([R+M]/2 method) in order to ensure proper performance of the fuel control system. Using fuel with an octane rating lower than 91 can create spark knock, which would cause the PCM to retard ignition timing to eliminate the knock. In a case such as this, poor engine performance and reduced fuel economy could result. Also, in severe knock cases, engine damage may occur.

Knock Sensor (KS) System Description
Varying octane levels in gasoline can cause detonation in high performance engines. Detonation is sometimes called spark knock. Spark knock causes the pistons and rings to vibrate and rattle producing the spark knocking sound.

To control spark knock a Knock Sensor (KS) is used. This system is designed to retard spark timing to reduce spark knock in the engine. This allows the engine to use maximum spark advance to improve driveability and to improve fuel economy.

The Knock Sensor (KS) system has two major components:

The KS module.
The Knock Sensor (KS).
The knock sensor is mounted into the engine block under the intake manifold. The knock sensor produces an AC voltage which increases with the severity of the knock. This signal voltage inputs to the Powertrain Control Module (PCM). The PCM then adjusts the Ignition Control (IC) to reduce spark knocking.

This powertrain system runs several tests of the Knock Sensor system. A fault in the KS system will PCM DTCs P0325 will detect KS Module or PCM faults, P0326 will detect low octane fuel or engine noise and P0326 will detect Knock Sensor and/or circuit faults.

Fuel Specifications
Use premium unleaded gasoline rated at 91 octane or higher for best performance. You may use middle grade or regular unleaded gasolines, but your vehicle may not accelerate as well.

Im well aware of knock, what it is, and how it affects performance, Ive been lurking around the 3800 SCed community for 5 or better years now, so knock issues have come up.

What you posted is true, but in an engine with low compression such as the 3.5 I dont see how knock is an issue at all. When GM says I can use regular gas right there in the owners manual I say go for it.

As for fuel economy, you and I have posted quite the same numbers on many occasions, ive pulled over 30mpg on good ol' 87 octane. I cant complain when it comes to performance either. Im just wondering what makes the LX5 so gosh darned special that it needs premium gas....high-compression? nope, forced induction? nope...maybe tuned for extreme performance? hell nope.

Im just saying that id like to see some numbers and proof before you go around telling every member here to use premium gas on a low-compression, otherwise non-performance engine. Because as of now it seems like your claims are based entirely on a seat of the pants feel, which may or may not be real.

Also, im not sure where you got that info, but octane is a measure of a fuel's resistance to being ignited. Also, from my understanding knock is caused by pre-detonation not post-detonation as your article describes.

So far, Im not convinced, and ESPECIALLY not convinced that a lack of premium gas is causing an overheating problem.

Also, since that article you posted seems to have originated from a Cadilliac forum, I dont know that it applies here. The N* V8s do run higher compression than our engines. How do you think they get all that power out of relatively small displacement engines?

I think that you are over-reacting. I didn't tell "everybody" to use premium gas, I suggested that atoyota4x4 try a tank to see if it could help with his over-heating situation. I use regular gas in my Intrigue but occasionally I toss in a few gallons of premium. The main question is whether the LXE engine uses the knock sensor system, not the compression of the engine.

I'm well aware of the points you raise about the low-compression/no forced induction but The GM folks HAVE issued different fuel octane recommendations for the 3.5 LXE engine, from regular to mid-grade to premium.

My thinking is that if, for some unknown reason atoyota's engine needs higher octane gas, such as massive carbon deposits in the cylinder, or his gasoline (unknown to him) is ACTUALLY lower than the stated 87 octane for some unknown reason, them he just might see some lower coolant temperatures by using premium gasoline.

Continuing on that theme, I would suggest that he try a bottle of LubeGArd Biotech engine protectant since it is very, very slippery stuff and alleges reduces engine temperature. I would also use a similar product in the transmission since it makes the tranny run cooler. The two together could make enough of a difference that his preceived overheating problem is solved or seriously reduced.

3/4 temp definitely means that something is wrong. In Pittsburgh, we've been seeing weather in the upper 90s, even over 100 in a few areas. I've also been in a lot of standstill traffic during this weather. The highest I've seen my temp gauge go is exactly to 1/2. In fact, for the most part while I'm idling in traffic, that's where it stays. When I'm moving 30+mph, even in the hot weather, it stays exactly half way between the 1/4 and 1/2 lines.


-and that's from someone that beats his car to death = the Intrigue heat guage should never get over that 1/2 mark. +3/4 is causing engine problems/issues. This aluminum block 3.5L dissipates heat amazingly well.

A poor performing engine/tranny will generate excess heat = keep your engine/tranny happy and cool for best performance.

Changed out that Dex-Cool and redid the tranny fluid and that coolant temp never gets close to the 1/2 mark. It's always exactly between the 1/4-1/2 now.