Got the O2 sensor replaced and it seems to have fixed the drivability issues. Took the truck out for a short drive and everything ran good. Will go for a longer drive in a few days...

Still waiting on the heads for the Jeep. Looking like I won't get them until after Christmas...

 

Well, christmas ain't that far away any more. Granted, they WOULD make a nice present for ya.

Take the truck for a longer drive, let everything get fully warmed up.... Make SURE the problem is resolved.

 

My short test drive was about 30 minutes... Around here that is a short drive. It was back roads with max 50 MPH speeds and then 8 miles of freeway @ 70 MPH driving so I think if it was going to act up it would have then. I'll be driving over to Yakima as soon as they call telling me my heads are done. That should be a even better test of it.
IT's 1PM here and they close at 5PM today and aren't open on the weekends so I'll guess I won't see my heads now until after Christmas and hopefully before New Years.

I've been working on other projects while I've been waiting for the heads.

 

So long as everything got fully warmed up, (which seems pretty likely.... ) I think you are in the clear.

 

Drove it over to Seattle twice last week and is running better again. I need to check my fuel mileage and see what I'm getting right now but I think it's around 13.8 MPG. I also need to get a downstream O2 fooler to fix that.

 

Howdy.
I have two different make trucks, but I think it's the Dodge O2 sensors that will briefly stick high or low voltage. If it sticks high the PCM thinks it's rich and will narrow the injector pulse, so that brief jolt is when the engine stops producing power when fuel is cut off.
Curious mind wants to know - did you get a misfire code before you fixed it? I think the PCM ignores the drop in rpm because it knows it just cut the injector pulse width, so may not throw a DTC for misfire.
Open loop O2 is ignored so that's why you weren't having the problem then. Easily overlooked because those jolts are so random.

You were right suspecting ignition but would have thrown a misfire. I was having the same jolts for a split second, but was getting 3/5 misfire codes - the 3/5 distributor electrodes on top of cap were covered in a nice coat of crispy white ash.

I recently got the 1/4" aluminum plenum plate off ebay for $40 so a bit of savings over the Hughes kit. Remember the intake torques are in/lbs, not ft/lbs. I was reading the 1 star reviews of the TTY bolts I ordered and was laughing at everyone who wasn't paying attention to torque units. Yeah buddy, those bolts might survive the first round of 24 ft/lb but not the final 84 ft/lb you applied

 

The only DTC I was getting was for my O2 sensor. And the truck is running better but I still need to work on it some more since IMO my fuel mileage isn't as good as it should be. I do need to do the plenum gasket once spring hits since I won't want to try it outside in the snow. I've got a set of short tube headers that I plan on installing on it also.

 

The plenum will have a negative effect on fuel consumption.....

Did you reset the PCM after changing the sensors? (have I asked you this already? )

Get the off-road y-pipe as well, you can splice a cheap cat in there if you like. That eliminates the MAJOR restriction where the two down-pipes hit the cat. They crunch down rather small there.

 

Yes I'd reset the PCM. And yes I know that the plenum can affect fuel mileage. If I could ever get my Jeep running I'd pull it out of the garage and could work on the truck in there but that doesn't seem to be happening anytime soon. Waiting for machine shop to call about the heads.

The PO had a different exhaust system installed and removed the cat. I need to get a fooler for it so I can turn the Check Engine light off. Just hasn't been a high priority. I'll have to look at it again to see if I can use the y-pipe or not.

 

Yeah, I would like to see you get the Jeep running good too. I think everyone following this thread is looking forward to that.