Are the Upper and Lower IM compatible with the USDM car? I got some from Goodfellas, and we think that swapping the JDM out and putting the USD back in will fix our problem, which is 2k idle and slow decelation in neutral.

Anyone have any ideas?

 

do you have the 13B RE UIM/ LIM?

and are you thinking of switching back to the 13B REW UIM/ LIM?

 

Sounds like a vacuum leak. It should work just fine, check to see if you may have left any ports open.

 

The only difference in the manifolds are EGR and AWS - that's it. I have JDM upper and lower manifolds on my car right now, runs and drives great.

Dale

 

Sounds like your problem is most likely with the throttle body (and or its components), not either the intake manifolds. Why exactly did you think new manifolds would fix the problem? Unless you have a crack in a manifold which is causing a leak, a different one isn't going to make a difference.

 

I think Kyle hit the nail on the head. When I responded to your PM, I forgot that I had sold you JDM mani's vs USDM mani's, but my advice still holds----check the throttle cable linkage, and you'll probably have to adjust the idle with one of the two adjustment screws, one on the top front of the tb and the hidden one underneath, below where the elbow bolts up.

 

whats the main difference in the JDM one vs USDM?

 

As I replied earlier in ur other thread, check the vacuum lines and a leak does sound probable. I'm assuming you used new gaskets right?

 

Check out post #4 in this thread.