Practically Classics Forum

Bought the Caddy today,drove home from Luton,drives really well.. no ball of fire but a lovely,relaxed,ultra quiet cruiser.According to the on board computer gubbins it averaged 21 mpg too,which isn't bad although it's probably all lies...








One issue though,it did stall when I was coasting down a hill on the Motorway on the way home ,I sudenly felt the steering weight up and of course no servo assistance,but it restarted alright and is fine now.Haven't had a look yet really,but I'm thinking maybe fuel vapourisation. It has a carb fitted (I think these were all efi) and the cat removed.

I'll probably live to regret it

The onboard 'puter will be working on American measurements, i.e. 1 gallon = 3.79 litres, not 4.54 as we would assume. Therefore as best I can calculate you were actually achieving closer to 25mpg

But it would also be working to American miles, which are 1.1904 times as long as Imperial Miles**, so the 21mpg may be correct.

















**-Yeah, of course that was utter bollocks, but I'm fookin' jealous of the bloke for having that lovely car, OK?.....

I'm happy with 21 tbh,probably about the same as my old Rover V8 was managing.

Don't know if this will help with the stall issue, but I lived in Canada in the eighties and had a couple of Oldsmobiles with fairly similar running gear as the Caddy. One of them had an insanely small (Not much bigger than my thumb) in-line fuel filter that clogged fairly frequently. It was a little paper thing with sort of brass end caps. If that's not the problem I would look for something other than vaporization. That is more likely to happen when the car has been standing after a run and the heat soak has had time to work it's mischief!

One of mine was an Olds 98 Regency and I was always amazed at how little fuel it used on a highway run so your numbers don't seem unrealistic.

I've been inspired to buy an '89 Olds, and while researching my purchase I saw something about one of the GM family of engines having an issue with occasionally conking out on overrun when decelerating from speeds over 55 (which was the prevailing limit in the US at time of manufacture) due to some part of the autobox not allowing the engine to spin freely? I can't remember exactly, I'll try & go through my history to find it again but chances are high it was on BlokeDownThePubPedia.

thats nice!

Awesome. Considering the size of the beast, 20mpg or thereabouts sounds pretty reasonable.

An update now I've had the time to look at it,it's not a carb (it certainly looked like one at a brief glimpse) but throttle body injection,with 2 injectors ... and the stalling issue certainly seems to have been because of a fuel filter that was well past it's prime.

Glad you've got it sorted. Inspired by you, I've bought an Oldsmobile which ran great guns for 200 miles, then conked out; closest approximation I could think of was fuel evaporation, but it turned out to be coilpacks - I should have recognised it, I've had an overheating coil in an Allegro before Still, that caused issues after just 5 miles!