Going to see a 98 Cadillac Seville STS on Saturday - what should I be checking out/asking?

Hello all,

Kinda related to my last post…

I’m going on Saturday to look at a 1998 Seville STS w/ 148,00 kms (91k miles). Owner says it needs brakes (not sure if all the pads/rotors or what yet), but otherwise that it’s good and a daily driver.

My question is what specifically should I be asking or checking when I see the car? My concerns are with the suspension and head gasket (Northstar engine) as those seem to be the big $$$ items on these cars?

I will also be having a mechanic check it out…it is worthwhile to do a hydrocarbon test on the coolant for an extra $42?

Please let me know if there is anything specific to Cadillacs/Seville STS’s that I should be checking or asking the owner about.

Thanks as usual…


If this car is within the Dexcool era, look carefully at the contents of the radiator.

Other than that, your plan is sound. If the mechanic is doing a compression test (a good idea), the hydrocarbon test is unnecessary if compression is within spec.

Good luck. Those are nice cars.

How can I check the contents of the rad? You don’t mean the overflow container?
Re Dexcool…if I buy this car, I can do away with Dexcool coolant right?

I don’t think a compression test is included in the safety check ($80)…I’ll see what that costs. Is that something you’d pay extra for?


That thing is one of the worst choices I know of. You are cruising for a wallet failure in the near future. Don’t give any more than small bills for that bucket of bolts. Call a parts place and see how much a rebuilt engine costs. You will be impressed.

You may also want to do a quick check of OBD codes, which can easily be done from the dash. Reads the codes out right to the display (if it’s a digital display).

When I bought my '98 Deville I quickly changed it from the green antifreeze to Dexcool. I’ve only seen warnings to keep it Dexcool. And I know the company that I bought it from had replaced the radiator 3 times in the four years before I bought it. Not sure if this relates or not.

I paid $400 for my car with 425,000 miles on it (now has 567,000). Second engine has around 420,000 miles on it. There have been several electrical connection problems in the past, which were solved when I replaced every mini fuse under the hood. Relays also sometimes go out. They plug into sockets, also under the hood. You may want to take a glance at the fuse/relay area under the hood to see if it has a lot of visible green corrosion.

The Northstar-based car presents a bit more challenge for people like me who like to maintain their own car. For example, to replace the starter, you have to lift a good portion of the top of the engine… Intake manifold, fuel injectors, throttle body, etc. just to get to it. (They put the starter in the V of the engine) I guess things like this would mean if you do not do your own maintenance, repairs at a shop might cost more than some other vehicles.

Thanks for your reply cartinkerer…I will check the codes, I read on the web how to do that.

Isn’t Dexcool “Death cool”? I’ve been warned to stay away from this stuff, but I guess Cadillac wants you to only use it?

That’s a lot of miles on your Deville! The Deville has the Northstar engine too right? Have you ever had any head gasket problems with your engines?

That’s too bad about getting at things like the starter…that sounds a bit daunting for my level of auto repair, but I would like to do as much as possible on my cars to save money and for the enjoyment of it.

Thanks for the tips, I guess I’ll see how it goes on Saturday!

Oh come on PDV, why do ya gotta burst my bubble?
I know these aren’t the most practical cars, but I seem to be attracted to these types of cars…92 and 98 Eclipse (before they were readily available in Canada), 85 Cutlass…now this…all over the map, but none are practical choices really. I’m sure a psychologist could tell me all sorts of terrible things about myself based on those facts.

“I’m sure a psychologist could tell me all sorts of terrible things about myself based on those facts.”
Naw, you just have wide, somewhat off-beat taste in cars. And that’s my professional opinion. :wink:

It’s a tough job but somebody’s gotta do it. They really tried to make something with that Northstar deal and I have to admire them for that. I might buy a non-running one some day and fool with it just to see this starter setup mentioned below. It is interesting. There isn’t a guarantee that the car won’t be good to you just because I say so. Dude.

Yup, definitely off-beat…haha…I really could never drive a Corolla or anything similar…might be reliable and practical, but that’s not why I love cars. :slight_smile:

I hope you are wrong PDV…but if it does totally kick me in the a$$, I will let you know and maybe you could buy it off me…? :wink:

Google “Northstar oil burning”. A quart per 1000 or 1500 may not bother much. The problem was with 96 - 99. The V6 engines apparently did not have this problem.