I have a 2001 LS that indicates it's overheating but does not actually appear to be. The first time it happened the temp gauge spiked and the check engine temperature message came on. I pulled over right away and popped the hood only to discover it was not hot or leaking. Restarted and it was immediately back to normal. Now, if you run the center vent the fan will turn on and the guage will jump up along with the warning and reduced power mode. If you run the heater on it goes back to normal. If you start with heat if doesn't do it at all? It makes no difference if you are on dual or single zone and if the AC is on or off. If you are on the floor vent it happens and on the floor vent it does not unless you lower the temperature below 70 or so. Is there an obvious answer?
LS V8 Overheating
- Thread starter Scottman
- Start date
joegr
Dedicated LVC Member
Yes, there is. It really is overheating. The way the gauge is buffered fools people.
Just about everyone on here has been through this. You need to change every plastic cooling system part and refill and bleed it exactly by the factory procedure. Use OEM parts. There have been a lot of bad experiences here with aftermarket. Do them all. Nearly everyone who has changed just the most obviously leaking part has found one by one that all the rest were too. It's a lot cheaper to do it all at once, than one part at a time over the next month or so.
Just about everyone on here has been through this. You need to change every plastic cooling system part and refill and bleed it exactly by the factory procedure. Use OEM parts. There have been a lot of bad experiences here with aftermarket. Do them all. Nearly everyone who has changed just the most obviously leaking part has found one by one that all the rest were too. It's a lot cheaper to do it all at once, than one part at a time over the next month or so.
joegr
Dedicated LVC Member
The plastic develops micro cracks. You won't see coolant under the car. If you know what it looks like, you will see the residue of coolant here and there on the parts. If you don't know what it looks like, then you will think it is just some dirt. The bigger problem than the coolant getting out, is the air getting in.
It would also be good to check the hydraulic fan system. Make sure the fluid is still good and is not contaminated. Also check the fan actuator. The fan should speed up when you turn the AC on. It should be very loud (jet engine) when the gauge goes over halfway.
The gauge goes to and stays at the halfway mark for a wide range of temperature. At 230, the car is in distress (high speed fan) but the gauge is still at the halfway point. At 240 or so it starts moving up. It is all the way up before 250. I certainly can't tell by holding my hand over the engine if it is at 220 (all's well, gauge at halfway) or over 240 (seriously overheating, gauge at max).
Correct fill and bleed: How to Drain the Lincoln LS Cooling System
It would also be good to check the hydraulic fan system. Make sure the fluid is still good and is not contaminated. Also check the fan actuator. The fan should speed up when you turn the AC on. It should be very loud (jet engine) when the gauge goes over halfway.
The gauge goes to and stays at the halfway mark for a wide range of temperature. At 230, the car is in distress (high speed fan) but the gauge is still at the halfway point. At 240 or so it starts moving up. It is all the way up before 250. I certainly can't tell by holding my hand over the engine if it is at 220 (all's well, gauge at halfway) or over 240 (seriously overheating, gauge at max).
Correct fill and bleed: How to Drain the Lincoln LS Cooling System
joegr
Dedicated LVC Member
Yes, on the thermostat.
There are a few threads on gen I V8 cooling system parts, but this one should get you going: Cooling System 3.9L - 1st GEN Lincoln LS w/ PN's
There are a few threads on gen I V8 cooling system parts, but this one should get you going: Cooling System 3.9L - 1st GEN Lincoln LS w/ PN's
Okay, I check the coolant level and it was not low at all and tjere is no sign of a leak. All the hoses look new. If you run the jeathe at 75 or more (I am in Phoenix and our current low is high 40's and highs in the high 60's) the temperature is normal. As soon as you reduce the temperature it starts overheating. Thermostat?
joegr
Dedicated LVC Member
Everybody says they don't have leaks, when they usually do. They just don't know what to look for. You are not going to be an exception to all the rest of us. Do it all (as outlined in the thread I linked), and you will probably never have this problem again (unless you keep the car for a long time). It could be worse, there is more to do on the 2nd gen.
I trust that you know what you are talking about and I do appreciate your experience, but can I ask a silly question...how can I have a leak if there is no missing coolant? Why does running the heater keep the temperature down? I will replace the parts as suggested but would like to understand.
joegr
Dedicated LVC Member
Only a small amount of coolant leaks out, so you don't notice it. At the same time (the bigger problem), air leaks in.
Anyway, you can start with just the thermostat. Don't say you weren't warned when the housing breaks as you are replacing the thermostat.
Anyway, you can start with just the thermostat. Don't say you weren't warned when the housing breaks as you are replacing the thermostat.
Aha... that explains it. I bled some air out yesterday after I checked the coolant and it is fine today, of course since air is the main culprit we know this is a temporary fix so I will get the parts ordered. Thank you again for your time and patience!
Ordering the parts from Tasca today...and just got a price from my local shop and they are telling me that the intake needs to be removed to replace the thermostat housing... really? Looks like I may be doing this myself!
joegr
Dedicated LVC Member
In my opinion, it has to be on gen II (though there are workarounds), but it does not have to be removed on the 1st gen that you have. You just need the right crow's foot wrench. Maybe the shop was thinking of a 2nd gen?
AmsterDutch
Dedicated LVC Member
I bent a 8 mm wrench into L-Shape and it worked perfect then just use a needle nose pliers for the last two-three turns ... If you bend a wrench just make sure it's thin and skinny
AmsterDutch
Dedicated LVC Member
I guess it’s a 5/16 but either 8mm or 5/16 will work just be careful when bending the wrench if you bend it to far I’m sure it will snap
Stevep-05LS
LVC Member
I know this was said already many times but I want to reiterate some info below, it would have saved $2k+ on my '05 LS V8 with a high temp issue. Once I found this forum it ALL became clear. I don't want anyone else to suffer what I did.
Change all the plastic parts at the same time.
Don't trust the dash gauge, use a reader to get the real temp.
Use OEM parts especially the thermostat & body - my last change was from a Gates T-stat & housing to a Motorcraft and the temp dropped over 30 Deg C. I did this to solve the cooling fan running steady, the fan no longer runs unless I'm driving hard on a hot day.
Also, I tried to change the plastic body that goes below the intake without removing the intake and I ended up with an intake leak. Someone suggested to loosen the intake bolts enough to get the back bolt out, I ended up putting new intake gaskets in. Maybe others know how to get the bolt out without touching the intake, that would be great.
It's running great now.
Change all the plastic parts at the same time.
Don't trust the dash gauge, use a reader to get the real temp.
Use OEM parts especially the thermostat & body - my last change was from a Gates T-stat & housing to a Motorcraft and the temp dropped over 30 Deg C. I did this to solve the cooling fan running steady, the fan no longer runs unless I'm driving hard on a hot day.
Also, I tried to change the plastic body that goes below the intake without removing the intake and I ended up with an intake leak. Someone suggested to loosen the intake bolts enough to get the back bolt out, I ended up putting new intake gaskets in. Maybe others know how to get the bolt out without touching the intake, that would be great.
It's running great now.
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I appreciate the feedback. Ordered the parts from Tasca and got the metal thermostat housing. I believe the housing can be removed with touching the intake... with a brake bleeerb wrench and needle nose pliers for the last couple of turns. Part arrive tomorrow and hope to get the job done Friday!
joegr
Dedicated LVC Member
Scottman and Stevep-05LS, just in case it isn't clear - you two are talking about two very different cars. The first gen thermostat housing can be replaced without removing the intake manifold, and there is a good aftermarket metal housing available.
The 2nd gen outlet tube can't be changed without removing the intake manifold (or sawing a bolt off - I don't recommend this shortcut at all), and there are no good aftermarket cooling system parts for the 2nd gen.
The 2nd gen outlet tube can't be changed without removing the intake manifold (or sawing a bolt off - I don't recommend this shortcut at all), and there are no good aftermarket cooling system parts for the 2nd gen.
Stevep-05LS
LVC Member
Thanks JOEGR for the clarity 