QuestionQUESTION: I just bought a 95 Deville with the Northstar engine. They said it runs hot. They changed the thermostat and water pump. There is NO knocking or tapping. Engine sounds wonderful! Where do I.M continue the search for the cause of the ovetheating?
ANSWER: Hello,
A common symptom with Cadillac engines with different specific solutions. The point of the matter is that by the time you hear knocking or see white smoke coming out of the exhaust is when it is too late!
You need to quit driving this thing and have someone determine and fix the problem. You have an aluminum engine and heads that cannot be subjected to any type of overheating. These engines are not like the old Chevy cast iron motors that you could get away running at 230 degrees for a short time doing no damage.
If you look at the archives on this site, Cadillac engines are notorious for overheating issues and if you drive long enough, you will be putting $4,000 worth of engine in it!
I love Cadillacs and have owned them for over 20 years. Some of the best cars I owned were Cadillacs and some of the worst cars I owned were Cadillacs too!
They are a nice car, but can be a real money pit and it is so hard to find a competent tech that can work on them. If you would have been at my shop and I had worked on it, I would have strongly suggested to go farther in looking for the problem and convincing you that you are doing damage to the engine driving hot.
I suggest you have the car taken back to where it was worked on and tell them to fix the overheating problem instead of just using guess work at your expense.
Personally, I am done with Cadillacs. Traded my last one off 6 months ago and now have a used Chevy.
Cadillacs are similar to Mercedes, BMWs and other high line cars. They are great to drive, but you also need a good bank account to maintain and service them.
The best Cadillac is a new Cadillac under warranty.
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QUESTION: I thank you for your insight on the Cadillac family and their potential problems. However, I didn't receive a clear answer suitable to my initial question. I think there was just some miscommunication. I just bought the car from an individual owner. They sold it at a VERY low price due to the accusation that it was overheating. That person said they changed the thermostat and water pump yet did not cure the problem. They started it, and it ran for 7 or 8 min with no overheating within that time. When I purchased it, I towed it home and have not touched it since. So now I just need to know what are the next possible causes for that model car to overheat. I don't have a lot of money to just drop it off at a dealer and say, "fix it".....'cause of course they will charge an arm and a leg to diagnose it first! If I can get a heads up on what else may be causing it, I can have a mechanic check that particular item. Any help you can provide will be greatly appreciated.
ANSWER: Hello,
There is no way I can possibly tell you what is causing the overheating because I am not physically looking at the car. NEVER take the car to the dealer and there are plenty of competent service garages out there for half the price and good quality.
I will give you some possibilities, but don't chase ghosts by changing parts until you figure out what is wrong. I told you the symptom of overheating is very common, but the list of what could be wrong is extensive. These are just a few examples:
Plugged radiator, cracked head or block, blown head gasket, bad water pump, plugged cooling system, inoperative cooling fan, radiator cap, engine performance problems such as running too lean, timing issue, computer, lack of coolant mixture that raises the boiling point, and that is what I can think of off hand.
I recommend having the vehicle looked at by a service facility. You state you don't have a lot of money and I understand, but as I told you this could easily cost you $4K if you continue to drive it hot.
Old Cadillacs are great for driving, but the average person cannot afford the repair bills when these engines begin to show problems. As I said, I know I have owned them for over 20 years.
The items I mentioned are things that need to be eliminated. Here is one more problem: You don't know what damage was done by the previous owner from overheating it and as you realize, their fixes did not work.
I just don't want to be the one that tells you to flush the cooling system, change the water pump (yes, this was a problem) change the radiator, replace the cooling fan only to find you still have an overheating problem.
I wish you luck!
rob
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QUESTION: Just wanted to thank you greatly. I tinkered with it enough on my own and finally found the prob. It was a mixture of two things. 1-they never bled the cooling system and 2- the line that runs along the top of the engine was COMPLETELY SOLID with rust deposits and debris. Car runs Excellent now. AND I PAID ONLY $600 for it!!!!!
Two final things......where is the level control fuse, or does it even have level control? The dash keeps saying check level control and I noticed that someone installed spring extensions on all springs to keep it up. Also, do you know if seats from a 99 Sedan Deville will fit a 95 with no probs?
AnswerHi,
Would appreciate you rating my answer. Just had a guy sour me on answering these questions and expected me to buy manuals for his car, so I could research for hours the answers to his questions for free.
I am glad it all worked out for you. You are one of the lucky ones. I guess I was right about the rust--
Have a great day!
Rob
