4.0L Compression Test Results
The 4.0L is actually in a 1987 MJ, but I thought I'd post it here as well. Hope to get some expert advice.
Had the fuel pump and all fuel injectors professionally replaced, and just completed a compression test. Here's what we came up with:
1 - 65 psi
2 - 90 psi
3 - 90 psi
4 - 60 psi
5 - 90 psi
6 - 80 psi
Although the engine only shows 97K, it was not well-maintained by the previous owner. We changed the oil immediately upon purchase, and the oil was the blackest I've ever seen. It even felt sticky. No telling when the last oil change took place.
Any opinions on what the readings above are telling us?