I recently bought a used 98 Cadillac Deville. The car ran fine the first day or two. It overheated the first time it took a trip on the freeway. It runs fine now, just not at 80. haha. I put a new serpentine belt and (spiny wheel) on because of the ishy noise it made. I know the car is leaking Coolant from somewhere, just not sure where. And im assuming it's a semi slow leak, it takes trips 2 1/2 hours north just fine. By the time we come home or soon after the check coolant level light comes on. Fill it back up with coolant and it just keeps disappearing. When the car had overheated someone had looked at it, did the pressure test on the line, they found no leak. He did mention that it looked like there was a coat of coolant all over the bottom of the car(probably from the overheat and erruption. I've heard many times of Cadillacs head gaskets going and I honestly can't afford the mistake of buying a lemon car lol lesson learned. The car will stall as well. for example, from sitting in park to long, going at a faster speed to stopping and waiting at a light. This becomes a big problem when trying to drive in the city. If you have any ideas of what may be the problem from this description it would be great to get an opinion so I don't get "raped" by the dealer. I really hope I can fix the issue with the coolant and stalling leak because I LOVE THIS CAR :) Thank you for your time and hard work!Sincerely, Amanda
Country: United StatesMake: CadillacModel: DevilleYear: 1998Engine: Northstar v8
Refilling the coolant,
engine light confirms toque convertor stuck on/off
pressure check on coolant line
I'm Neal and I am here to assist you. Only accept when you are happy with my assistance. If I can't help I will open your Question to other experts.
I would suspect based on my experience that you have a very small head gasket leak, and you do not want to replace the head gasket as it would cost more than the car is worth. I would try a product called Blue Devil, Ihave had tremendous success in cases even worse than yours. It is a high endblock and head gasket sealer. Most parts stores carry it. Make sure you follow the instructions and chances are extremely good it will fix your issue permanently or at least for a very long time. They advertise a 85% success rate on the northstar engines. Here is a link to the manufacturer if you want to read more about it.
I will test this out and accept when it works, I hope it works. Would this fix the stalling problem? or is that a whole nother deal?Wondering if coolant can also leak from tubes and hoses and such? or resevoir leak.
I cannot say for sure about the stalling, that could be fuel pressure. Coolant leaks can occur other places but you said that a pressure test showed no leaks.
I have seen a lot of these and it is usually the head gaskets.