- Location
- Roanoke VA
I've been fighting this problem for a couple of weeks. I have a miss/stumble only on cold mornings and only on acceleration. After the engine warms up it runs fine. When I bought this XJ a few months ago the engine was blown and it was partially torn down and missing a few parts. The 4.0 has been rebuilt(by a local engine builder), it was bored 40 over and the head was milled and the block decked. Here is a list of what is new, some of which was replaced because they were not on the Jeep.
TPS, O2, CTS, IAC(Holly)
I've replaced and/or cleaned the grounds.
I've tried 3 different sets of plugs(Champions/Autolights) and wires, I'm running NGK right now.
New cap and rotor
I've double checked the distributer indexing, its on #1 TDC.
New injectors.
New fuel filter.
The intake and TB are clean.
Its pulling 18hg vacuum
I've checked the fuel pressure and it is in spec both at idle and with the vacuum disconnected.
EGR is blocked.
There are no vacuum leaks.
I'm getting 18 mpg city.
I've got a CPS and a MAT on order and will install this weekend. I've checked the sensors before replacing and they were all good, but decided to change them anyway(I'll keep the others for spares).
This XJ is being restored to original since it belonged to my dad before he died and it got sold and then I found it and bought it back. I would really like to get this mechanical problem fixed so that I can move on with the resto.
Anybody have any ideas?
TPS, O2, CTS, IAC(Holly)
I've replaced and/or cleaned the grounds.
I've tried 3 different sets of plugs(Champions/Autolights) and wires, I'm running NGK right now.
New cap and rotor
I've double checked the distributer indexing, its on #1 TDC.
New injectors.
New fuel filter.
The intake and TB are clean.
Its pulling 18hg vacuum
I've checked the fuel pressure and it is in spec both at idle and with the vacuum disconnected.
EGR is blocked.
There are no vacuum leaks.
I'm getting 18 mpg city.
I've got a CPS and a MAT on order and will install this weekend. I've checked the sensors before replacing and they were all good, but decided to change them anyway(I'll keep the others for spares).
This XJ is being restored to original since it belonged to my dad before he died and it got sold and then I found it and bought it back. I would really like to get this mechanical problem fixed so that I can move on with the resto.
Anybody have any ideas?