Putting a newer 2006 Wrangler 4cyl engine in a 1990 wrangler..

Possible, yes. Cost effective, probably not. You also have to transplant the electronics (computers etc) By the time your done the cost will probably be close to that of a newer used Jeep or a swap-out to a compleatly different motor.

This guy put in a Ford 5.0 (302) engine

Anything is possible. I would reject this project though. Would you know how to connect the 4 cylinder's computer and sensors into your 1990 vehicle's wiring system? How about its more modern and more complicated fuel injection system? It would be a lot of work, just to make use of spare parts that happen to be available. You could rebuild the 258 cid engine for less trouble and less money. That's what I would do.

Cheers,

Earle

Why would you replace your 258 with a 4 cylinder? If your looking for better gas mileage...it's not worth it. The loss of power far outweighs any savings in gas you might realize. You will hate the 4 cylinder and wish you never put it in...trust me. The 258 is a veritable workhorse for Jeeps. Replace your old one with a rebuilt one.

Main reason for the replacement right now is monday (I think but could be wrong)... only have to pay $100 for the new engine/transmission, wiring and computer as the guy spoke of earlier... Also I believe it will have fuel injection which would be nice...

Probably a pain to mount in and get running though I'm sure.

The fuel injection requires a different fuel tank, pump and fuel lines. I doubt that the TJ tank would fit your vehicle, so this would have to be a custom installation. Unless you get the transfer case with that transmission too, although they are similar there is a drive coupler between the transmission and transfer case that certainly is different. This part requires disassembly of the transfer case to replace. Your YJ has a cable drive speedometer. The new engine requires an electronic drive gizmo to make the vehicle speed sensor work. Motor mounts? Hooking up the exhaust system? The details will kill you on a transplant like this. I haven't even begun to list them.

A ring job and bearings on that 258, if you have moderate mechanical skills and can follow directions, may not be so bad money wise. What is the compression on your existing engine? You can rent a compression tester at maybe Autozone or Taylor Rental. Look for equipment and tool rental in the Yellow Pages. Is it burning oil? It might just be valve stem seals.

Cheers,

Earle

Drive a four banger, before you disappoint yourself, BIG TIME! God Bless America, Bill O|||||||O mailto: snipped-for-privacy@billhughes.com

I may be remembering this wrong, but I think that one potential problem will be the drive shafts. As I remember from research while swapping out a BA10/5, the AX5 used with the 4-banger is shorter than either the T4/5 or AX15 by about an inch - enough to make the front shaft too long and the rear one too short. Take a close look at that.

The 2006 had a 6-speed manual gearbox. Although it is an awesome gearbox, it is also longer than other gearboxes used in previous years. As a result, you will need the front and rear driveshafts of the 2006 TJ, and find a linkage for the transfer case.

Fitting the 2.4 lt engine would be a real task. You will definitely need the computer (PCM), and the dashboard of the 2006 TJ, the fuel pump (inside the tank) of the 2006 TJ, the SKIS module and lock (immobilizer) unless you have access to a DRB-III scan tool from a dealer and know how to disable all the unneeded gizmos. I wouldn't want to get in this trouble, even if I was given money to do it. It would really be easier to fit an other FI computer and reprogram it to run the 2.4lt engine.

If you want fuel economy, and are willing to mess with a difficult engine swap, you should consider putting a diesel engine in it instead.

This project would cost much more than what you are trying to save. Better rebuild your current engine.

Bill Spiliotopoulos, '96 XJ, '06 TJ.