Help!!!!!!!. I dropped a 99 4.2 in my 98. Install went smooth but I had to use my old intake manifold. Here's my problem. The lower intake manifold uses 2 different gaskets depending on the build date. My orginal engine (11-97)or a newer one for later. Which one do I use. Also the CMP sensor has a different keyway. I thought I could just switch the CMP sensors but it tripped a code.

 

the CMP does have to be aligned just like a distibutor for it to work right. they have a special tool they insert at tdc #1 then rotate till it drops in with tool in it then tightn down hold down.

as for the gaskets you either have to just get both sets and match it all up and see what fits best or maybe someone has already had this problem and they will post soon.

 

Tom
I'm doing that now ( early intake on a later motor ) How did you make out? I was told the earlier lower intake gasket is one piece and the later gaskets are seperate. Which did you use? let me know. OH How did you make out with the CMP ?

 

you'll need to use the build date for the old engine. the difference in the gaskets seem to be for the intake manifold . the Block casting seems to be the same.
good luck.