simple swap (after searching lots)

[malachi]

So after searching about 3 hours, I gave up on that and decided to post a question.

I am working on a 1998 Buick Century w/3100. Motor is rocking really bad, no power, and misfiring like mad. Quite a bit of valve train noise aswell.
I have replaced CAS, MAF, MAP, TPS, CTS, clogged CAT, timing chain, fuel delivery, all 3 ignition coils, ignition module, plugs, wires, and a few other things I cannot think of off the top of my head.

At this point I think he has a busted but silent piston/rod.
I am continuing as though the engine is bad and needs replacement. My only experience with the 3100 motors is the LIM gasket on a few.
I have been searching for a good motor, and was wondering what all years I can install with minimal mods. I am more concerned with the basics of bolting it up and if it will run on the stock system. HP and types of sensors/plugs are not too important if I can just swap over or replace brackets and what not.
Thanks for any help you guys can give me.
Sorry about being a noob and asking questions which are likely easily found.

[bszopi]

96-99 3100s should be a direct swap over. I don't think the EGR moved until 2000, but even then, its still the same EGR, just mounted differently. Then there is always the 96-99 3400 as well, if you want an increase in power.

[malachi]

Sweet, I was able to find that the 97-99 would fit from the Lumina and Monte's..... Would the 3400 play nice with the EPROM? Or is it just gonna toss a CEL and go into a limp mode?
As far as EGR goes, if I got the correct one for the engine, will it make any difference? Will an older 3100 fit at all? Or do they have a different igntion system?
If it wasn't a Buick w/4 doors I might wanna try and build it for speed, but right now, I just need the car running for the lowest dollar amount.
Thanks for the relay. VERY helpfull information.

[bszopi]

Anything before that has a completely different EGR, so it won't work. For a good read on the 3400 swap, or even a 3100 swap, download the guide at www.3400swap.com

[malachi]

Fantastic.
Thank you.

[malachi]

So a 2000 Lumina should bolt up? As long as I am ready to make a few mods for the EGR system? Or just leave it alone?
I am not afraid of donig what needs to be done to make it fit.
I found a rear end wreck, so hope to get working on this ASAP.

[bszopi]

Yes, it would work fine, and is actually an improvement over your current engine, as it has the newer (ie, better flowing) top end. But yeah, it is basically a direct bolt-in.

[malachi]

Yes, it would work fine, and is actually an improvement over your current engine, as it has the newer (ie, better flowing) top end. But yeah, it is basically a direct bolt-in.

w00t for GM then!
Thanks, I am now going into the car with confidence!

[1988GTU]

What diagnosis have you tired? I see you were swapping parts (can get tiring and costly) , but have you scanned for data/errors? IS there a/any current fault codes or alike? Being a 98 WILL show A LOT of knock counts if something internal is busted, are you getting kr?

[malachi]

I was getting "random missfire", some EGR related codes. I forget what else. But no knock codes that I remeber. I was using an old Snap On red scanner. It was only up to date to about 2002 or so.
There was some noise in the upper end. Chatter but it was kinda loud at start up.

I bought a newer motor for it, but have not had time to install as yet.

Thanks for the thoughts!