Jeep Commander Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
18 Posts
Discussion Starter #1
I'm swapping out intake manifold gaskets this weekend on our 07 XK 3.7. I have a possible air leak on Bank 1 so I want to change them out. I know the proper procedure is to pull the motor mounts and lower the engine but there has to be a easier way. The insulation is cut already above the TB on ours so i wonder if that will give me enough clearance. I know it's been off due to it needing new cyclinder heads at some point. There is absolutely nothing online on removing it. The gas mileage is very poor so I'm hoping this is it.
 

·
Premium Member
Joined
·
294 Posts
Testing

It might be worth checking as much as possible to make sure that you have a intake leak, try a can of carb cleaner with the tube on the spray head so as to narrow the area of the check, with the engine running spray around the intake runners to the head a little at a time, give it some time in between runners to see if the engine idle changes. If you have gone all the way around the engine and no real change in rpms it may not be the gasket.
Might be worth a try.

Swanny
 

·
Registered
Joined
·
18 Posts
Discussion Starter #3 (Edited)
It might be worth checking as much as possible to make sure that you have a intake leak, try a can of carb cleaner with the tube on the spray head so as to narrow the area of the check, with the engine running spray around the intake runners to the head a little at a time, give it some time in between runners to see if the engine idle changes. If you have gone all the way around the engine and no real change in rpms it may not be the gasket.
Might be worth a try.

Swanny
I used TB cleaner on every vacuum hose and around the manifold with no luck. Then I tried propane with no luck. The reason I think it might be the Bank 1 intake manifold gasket is I have a high long term fuel trim on B1. When I hold the rpm at 1500-2000 the LTFT comes back to 0. Bank 2 hovers right around 0 at idle. I recently replaced both cats and I want to make sure it's running as good as it can.

I have a thread in the new member section with a little history on our XK. A previous owner had new heads installed I assume from being overheated. I believe that's what ruined the B1 converter. We were getting P0420 and the Jeep began to feel really sluggish.

I see you're from cement city. I'm actually in Adrian. Pretty close by
 

·
Super Moderator
Joined
·
5,881 Posts
I used TB cleaner on every vacuum hose and around the manifold with no luck. Then I tried propane with no luck. The reason I think it might be the Bank 1 intake manifold gasket is I have a high long term fuel trim on B1. When I hold the rpm at 1500-2000 the LTFT comes back to 0. Bank 2 hovers right around 0 at idle. I recently replaced both cats and I want to make sure it's running as good as it can.

I have a thread in the new member section with a little history on our XK. A previous owner had new heads installed I assume from being overheated. I believe that's what ruined the B1 converter. We were getting P0420 and the Jeep began to feel really sluggish.

I see you're from cement city. I'm actually in Adrian. Pretty close by
Jeepdude,

Did you ever finish this intake manifold gasket swap?

If so, how did it go?

Did you have good results?
 

·
Registered
Joined
·
18 Posts
Discussion Starter #5
Jeepdude,

Did you ever finish this intake manifold gasket swap?

If so, how did it go?

Did you have good results?
I ended up doing the gasket swap. When I pulled the intake off there wasn't any obvious signs that a gasket was damaged. But the gap where the intake is molded together on B1 seemed a little larger then the other side. So before I put it back together I put some black RTV gasket maker along the seam. Reinstalled with new felpro gaskets all new injector o-rings and I swapped all the injectors and coils from B1 to B2.

It did fire right up no issues. We have put about 150 miles on it since I did the swap. My LTFT on B1 still seems a tad high at 6 to 6.5%. While B2 averages 1 to 1.5 %. Im kinda at a lost. This engine is pretty dang basic to not being able to find a vac leak. Only thing I really can think of is maybe the intake is slightly warped from being overheated.? I need to find s shop that has a smoke machine. Maybe that will work.

All in all removing the intake manifold was a pretty easy task. I did have the pull the 1 long bolt on the passenger side motor mount to gain the clearance to remove the intake. I found the hardest part was removing the 2 small bolts from the EGR tube.

I took a bunch a photos but I don't know how to upload them from my phone.
 

·
Super Moderator
Joined
·
5,881 Posts
I ended up doing the gasket swap. When I pulled the intake off there wasn't any obvious signs that a gasket was damaged. But the gap where the intake is molded together on B1 seemed a little larger then the other side. So before I put it back together I put some black RTV gasket maker along the seam. Reinstalled with new felpro gaskets all new injector o-rings and I swapped all the injectors and coils from B1 to B2.

It did fire right up no issues. We have put about 150 miles on it since I did the swap. My LTFT on B1 still seems a tad high at 6 to 6.5%. While B2 averages 1 to 1.5 %. Im kinda at a lost. This engine is pretty dang basic to not being able to find a vac leak. Only thing I really can think of is maybe the intake is slightly warped from being overheated.? I need to find s shop that has a smoke machine. Maybe that will work.

All in all removing the intake manifold was a pretty easy task. I did have the pull the 1 long bolt on the passenger side motor mount to gain the clearance to remove the intake. I found the hardest part was removing the 2 small bolts from the EGR tube.

I took a bunch a photos but I don't know how to upload them from my phone.
Warping occurring from major overheating is always a possibility and that may very well be why the previous owner got rid of it.

If nothing else, at least you eliminated the gasket as a possible cause.
 
1 - 6 of 6 Posts
Top