2000 Wrangler, 4.0, Manual, 165k miles.
I've had the P0300 for about two months. I replaced the CPS a year ago with a Mopar unit. Spark plugs a few weeks ago with Autolite XP985. Delphi fuel pump 6 months ago. Heat shields to avoid heat soak issues. Tested coil pack using this method and it seemed to fire well.
Dry compression test:
145
115
135
125
170
180
Wet compression test:
165
170
145
155
Didn't have a good funnel for the last two cylinders since I'm on the road. Will test again once I'm in a better spot. Some of those increases makes it seem like piston rings and cylinders 5 and 6 are pretty high, so possibly valve seals (?)
So I'm posting this in case I'm missing something. I might have access to a leak down tester, but we'll see.
In the meantime I'm looking at crate engines since I don't have the expertise or time to rebuild it. Any recommendations?
I've had the P0300 for about two months. I replaced the CPS a year ago with a Mopar unit. Spark plugs a few weeks ago with Autolite XP985. Delphi fuel pump 6 months ago. Heat shields to avoid heat soak issues. Tested coil pack using this method and it seemed to fire well.
Dry compression test:
145
115
135
125
170
180
Wet compression test:
165
170
145
155
Didn't have a good funnel for the last two cylinders since I'm on the road. Will test again once I'm in a better spot. Some of those increases makes it seem like piston rings and cylinders 5 and 6 are pretty high, so possibly valve seals (?)
So I'm posting this in case I'm missing something. I might have access to a leak down tester, but we'll see.
In the meantime I'm looking at crate engines since I don't have the expertise or time to rebuild it. Any recommendations?
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