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1989-90 Cadillac Fleetwood Brougham?

Posted by westranch (My Page) on
Fri, Jul 28, 06 at 11:03

I have a unique opportunity to purchase an estate vehicle with low miles. (around 30k) The car has always been garaged and serviced. It comes with all receipts on work and service performed. Does anyone know anything about these large rear drive vehicles? Is this the model with the 4-6-8 engine? Should I stay away from it if it is?

Follow-Up Postings:

RE: 1989-90 Cadillac Fleetwood Brougham?

My (former) father in law had a caddy in the early 80's with the 8-6-4 engine. Seemed to work ok but you could feel every time it added or dropped cylinders. Engine was always smooth in operation but felt like an auto tranny shifting gears. Thought they dropped that engine idea long before '89.

My brother had a couple cadillacs. Don't recall him having any trouble with them till they were pretty old.

I'm not a cadillac fan myself, but they seem to be good cars. Just remember that a '90 cadillac has about the same value as scrap iron so don't pay too much, like $3500 or so tops in my area. What it's got going for it is the low mileage and that advantage will go away as soon as you start to use it.

Also keep in mind that it's likely to have some old car issues regardless of mileage. The rubber parts like seals, belts, hoses and tires go bad whether the car is driven or not. Same goes for moving parts like water pumps, ac compressors, alternators, shocks, ect. Don't get me wrong, I think old cars with low miles are a good buy. Just don't expect it to have the same reliablity as if you bought a 2 year old car with the same mileage. jmo

RE: 1989-90 Cadillac Fleetwood Brougham?

The NADA site says the car is worth $2,600 plus $800 for low miles for a total of $3,400. That's average retail.

AS far as the 8-6-4- engine, I really don't think many of those were in the Fleetwoods. I had a friend that had a Cimmaron with one and... well that was nothing more than a Cavalier anyway and it was a pure piece of garbage.

RE: 1989-90 Cadillac Fleetwood Brougham?

Thanks! That's right on target for what I was willing to pay. The car is actually a '93 DeVille. I saw the car today. The owner's daughter didn't know what model or exact year it was. She just said it was huge. That's what made me believe it was the Brougham. I guess our ideas of huge vary. LoL. Is around $3500 still on target for the DeVille with 37K?

RE: 1989-90 Cadillac Fleetwood Brougham?

RE: 4-6-8 Cadillac Engines

Eaton, the company that I worked for, developed the valve switch-out assembly for Cadillac's 4-6-8 engine. So far as I know, it was used for only one model year. It was a stop gap measure to aid Caddy's fuel mileage, and to gain field experience, while they revised their product line-up. Their plan was to move to something different, but if the 4-6-8 engine, by chance, became popular with their clinetelle, they would have continued it.

The way it worked was to let the valves of the chosen cylinders stay closed. There was no change to the ignition so the sparkplugs of the disabled cylinders continued to fire. In operation, the closed cyliners would leak enough gases past the rings to arrive at an average cylinder fill so that at the bottom of the piston travel, there was a vacuum in the cylinder, at mid stroke it was neutral and at top it was mildly compressed. The closed cylinder became effectively an air spring and contributed only very small losses.

The other tricky part was the selection of the cylinders to shut off. The correct ones had to shut off to keep a smooth running engine. You can have even firing for 4 and 8 cylinders in a 90 deg V8, but it will be uneven firing with 6 active cylinders. The uneveness of the 6 cylinder operation isn't too noticeable if the engine RPMs are high enough, but becomes noticable as the engine approaches idle speed.

Furthermore, an algorithm was developed to move the shut-off selection around among the cyulinders so that each time a shut-off occurred, a different set of cylinders were selected. This was done to even the wear among the cylinders.

This shut-off operation was controlled by the engine controller (computer). This could be an issue. I don't know if this required a special computer chip, or if the current chip was adequate and only required different program. Whatever the case, should the computer controller ever needed to be replaced, it might be a rare one to find. Check with your local Cadillac dealer. Also, you might wish to find out if you can disable this feature, and what the cost would be for a valve job.

RE: 1989-90 Cadillac Fleetwood Brougham?

1965 fleetwood is among the rarest cars i've seen. I traveled far places like europe and asia and but i oly saw four of them with their great designs and mods. The said car has the finest engineering and uses one of the most powerful engines on the market - the V6. Though i am sure, owners find difficulties when it comes to maintenance since the parts of this vehicle are hard to find. Good thing there were sites out there where you can see Cadillac repair questions. All you need to do is to place your queries and wait for the answer. Plus, you could also do online diagnostic thru OBD codes that you have seen from your auto.

RE: 1989-90 Cadillac Fleetwood Brougham?

The V8-6-4 engine was used in 1981 only, except for a few limos and such built in the few years after that; the standard Caddys were switched to the aluminum 4100 (which also proved unreliable). Great idea actually even if it was not well-executed; in recent years "cylinder deactivation" as it's now known has started to reappear, including on several General Motors products as well as on Hondas and such.

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