Acceptable Engine Compression for a 99 TJ 4-cyl with high mileage?

[wesleywest]

Howdy Everybody!

I've searched the web and the forums trying to find an answer but I haven't found exactly what I'm wanting to know.

I'm going to look at a 1999 TJ 4-cylinder and I was wanting to know what an acceptable range is for the engine compression for a Wrangler with around 200,000 miles would be.

I've got a compression checker as well as an error code reader that I can put on the Jeep to check it all out so I just was hoping to know what an acceptable range is. I read somewhere that for low mileage 155-185 is a good range, but since this vehicle has a ton of miles I would just like to know what's acceptable and what's a red flag.

Oh! If you also have any other suggestions for specific things to check out that would be outstanding. I've been interested in a Jeep for a while but I don't have a lot of specific knowledge. All I know is to just check for signs of excessive rust, and so forth.

Thanks a ton!

Wesley

 

[RudeDog]

I beleive it should be at or above 100 psi. Check with all plugs out, throttle open, and a fully charged battery

 

[Bounty__Hunter]

Make sure the transmission, if manual, shifts smoothly between gears. Notchy shifting may mean the synchros are on their way out. Bad synchros are very common with the manual. If it shifts smooth, change the gear oil in the transmission to Redline MT90 once you buy it.

Check the level and color of the ATF in the transfer case.

 

[wesleywest]

Thanks for the answers guys! I went and looked at it and the engine seemed to be great, pulled well, compression was acceptable, the transmission was also smooth.

One problem was when turning hard it would rock fairly violently, long story short I took it back to the guy and he had no idea himself (he doesn't drive it regularly as he has health conditions preventing him from doing so) and he was super nice, felt really bad and we immediately drove over to a local repair shop where he knew somebody that took a quick look at it and determined that the U joint was rusted out and needed replacing. The gentleman selling it offered to get it fixed as he didn't want to sell it with the problem so it should be out of the shop Monday. I left him a deposit and told him after it's fixed that I would buy it pending a second test drive to insure that the problem was resolved.

We agreed on $4000 for a price. It needs a new soft-top but besides that it seems to be in relatively good shape, I checked pretty thoroughly for rust and didn't find anything out of the ordinary for a vehicle that's over 10 years old. Does this seem like a fair deal?

Here's a pic of it in case anyone would like to see it: