1986 Buick Park Avenue knocking

My uncle passed away earlier this year and my younger brother bought his 1986 Buick Park Avenue with a rebuilt 3.1 V6. The engine was rebuilt maybe 2 yrs ago and has somewhere around 20k miles on the rebuild. Well, the engine knocks consistently and the knock is pretty loud. Mechanics say it is something in the lower engine, probably a bearing. The car rides and drives almost perfect other than the knock in the engine. We can’t find a 3.1 v6 anywhere. Is it possible to get a newer 3.8V6 and have it fit in the engine compartment and bolt up to the transmission? I know its probably best to scrap the car but the rest of the car is in great mechanical shape. Mechanics keep telling us not to put any money in it and expect it to go out on us anytime.

I have been looking at the larger auto parts stores websites and not one of them lists the park avenue as having a 3.1L available. All of them only list the 3.8L as the engine option for that car. So I guess I am still curious as to how new of a 3.8L engine may fit in and easily hook up and go for us.

The 3.1L is a rare bird in the GM line of engines. The son has a Buick with this engine in it.

Here’s the problem you’re going to run into. Unless you install another 3.1L engine in that vehicle with the same Vehicle Identification Number or VIN, The engine computer will be a miss-match. I don’t know why GM did this, but I presume it has something to do with the advent of OBDII coming on the scene? But I’ve installed engines in GM’s of this vintage, and the first question they ask is “What’s the VIN?” when purchasing these engines from a recycler. And if you find a 3.1L engine that’s compatible with your VIN, consider yourself lucky.

Tester

Yeah we can not find a 3.1L anywhere. Was hoping that maybe a 3.8L would drop in. Ah well, I guess I will end up selling it to a scrap guy.

Is it FWD or RWD??

I haven;t looked closely but I believe it is FWD. I just drove it for the first time today after my brother said it died and he thought the engine blew. I drove it 10 miles and besides the knock it is in great shape.