Aftermath of 3.8L engine swap
Thread Starter
JK Newbie
Joined: Jan 2014
Posts: 3
Likes: 0
From: Nampa, Idaho
Aftermath of 3.8L engine swap
Hi Jeepers!! Complete engine rebuild done after a oil consumption issue spun a bearing while my dipshit kid was using it to commute to and from work
....engine is back in the jeep. Starts and runs...rough. Sounds like it has a miss in it. I did notice last night when it was kinda dark right after I started it I saw what looked like spark coming from my plug wires right at the connection to the plugs. all 4 on the drivers side were doing it. Anyone know whats going on with this????
....engine is back in the jeep. Starts and runs...rough. Sounds like it has a miss in it. I did notice last night when it was kinda dark right after I started it I saw what looked like spark coming from my plug wires right at the connection to the plugs. all 4 on the drivers side were doing it. Anyone know whats going on with this????
JK Junkie
Joined: Dec 2007
Posts: 3,343
Likes: 3
From: Amherst, Ohio
Unless you swapped in a V8 the driver side should only have three..
Who swapped the motor in? There have been several threads on motors running rough after a swap. Did you check it for any codes first?
Who swapped the motor in? There have been several threads on motors running rough after a swap. Did you check it for any codes first?
JK Newbie
Joined: Oct 2009
Posts: 52
Likes: 0
From: Cleveland
I recently finished my 3.8 swap. My engine sat in the garage for at least 5 years being rotated occasionally by me and the previous owner.
First start on mine produced p0300 dtc's. I was very concerned. I started with wires and isolated which cylinder was not firing. I found there was spark at the wire. Next I swapped the plug with one from the old engine. At the same time I put injector cleaner in the tank. It gradually got better over the next several min of running. I only let it run for a few min at a time, but it was very rough.... Like it was running on 5 cylinders
Eventually, it worked itself out and finally the MIL turned off on its own.
Perhaps your wires are nicked? Not fully seated? Plugs cracked or not tight? I hope this gives you a place to start.
-Chris
First start on mine produced p0300 dtc's. I was very concerned. I started with wires and isolated which cylinder was not firing. I found there was spark at the wire. Next I swapped the plug with one from the old engine. At the same time I put injector cleaner in the tank. It gradually got better over the next several min of running. I only let it run for a few min at a time, but it was very rough.... Like it was running on 5 cylinders
Eventually, it worked itself out and finally the MIL turned off on its own. Perhaps your wires are nicked? Not fully seated? Plugs cracked or not tight? I hope this gives you a place to start.
-Chris
Last edited by RubiKean; Oct 10, 2014 at 03:39 PM.
Thread Starter
JK Newbie
Joined: Jan 2014
Posts: 3
Likes: 0
From: Nampa, Idaho
I recently finished my 3.8 swap. My engine sat in the garage for at least 5 years being rotated occasionally by me and the previous owner.
First start on mine produced p0300 dtc's. I was very concerned. I started with wires and isolated which cylinder was not firing. I found there was spark at the wire. Next I swapped the plug with one from the old engine. At the same time I put injector cleaner in the tank. It gradually got better over the next several min of running. I only let it run for a few min at a time, but it was very rough.... Like it was running on 5 cylinders Eventually, it worked itself out and finally the MIL turned off on its own.
Perhaps your wires are nicked? Not fully seated? Plugs cracked or not tight? I hope this gives you a place to start.
-Chris
First start on mine produced p0300 dtc's. I was very concerned. I started with wires and isolated which cylinder was not firing. I found there was spark at the wire. Next I swapped the plug with one from the old engine. At the same time I put injector cleaner in the tank. It gradually got better over the next several min of running. I only let it run for a few min at a time, but it was very rough.... Like it was running on 5 cylinders
Eventually, it worked itself out and finally the MIL turned off on its own. Perhaps your wires are nicked? Not fully seated? Plugs cracked or not tight? I hope this gives you a place to start.
-Chris
I did purchace some new plugs and wires today to put in tonight or tomorrow. Ill keep you posted how it goes afterward...thanks again everyone
JK Freak
Joined: Jun 2014
Posts: 577
Likes: 0
From: Harlingen Texas
P3000-p3006 refer to engine misfire. MIL is the malfunction indicator light (check engine light)
I would start with replacing plugs and wires.
you mentioned that you rebuilt the motor yourself, does that include cam shaft installation?
I would start with replacing plugs and wires.
you mentioned that you rebuilt the motor yourself, does that include cam shaft installation?