hi all
i have a 98 ford exp 4 wd with the 4.0 sohv engine my problem is cel is on, had codes pulled at advance auto says bank 1 and 2 too lean and misfire in cylnder 2 . engine runs great at highway speeds but at a red light or sitting in the bank drive thru it idles like its got a dead plug . i have replaced the plug wires with ford dealer parts as i replaced the spark plugs from dealer also, that didnt help. exp has 136000 miles on it does not use oil . ive been reading a lot of post on here and it seems like that the upper and lower intake manifold gaskets might need to be replaced? does this sound like it might be my problem also? if so how hard a job is it .compared to changing the dreaded headgaskets on a 94 ford thunderbird as i just did that on my wifes t-bird last month did that with no problems. any insight would be greatly appreciated .
thanks in advance
911bear

 

Yes sounds like the intake gaskets. PM me your email and I'l send you a detailed write up with pictures.

 

Sending you what I have now but it's for the regular 4.0, not the SOHC motor. So it's a lot different. Sorry about that but it might help a little. Any repair manual should give you enough to do the job too.

 

Thanks For The Info Jharger Looks Great!

 

I had a similar problem with a Chevy Lumina and the problem was a clogged fuel injector.

Matt

 

i went to the ford dealer today and told them what my explorer was doing and he told me it sounded like a blown intake gasket , he said they had done 3 this week , we,ll i told him to give me the parts i needed and he handed me a small box ford part # YL2Z-9E473-AA TOLD ME IT WAS AN updated kit it came with 6 blue rubber o-ring type gaskets 2 black rubber gaskets a new left side timing chain tensioner a small brass plug and a plastic stick , it seems to me that there should be more to it than that it would appear that it should have a "vally pan" type gasket also any feedback on this kit would be greatly appreciated . thanks very much for all the help so far!
911bear

 

Dont know if this will help but I had the same symptoms with my 01 explorer. I had sys bank 1 and 2 lean also. Found my problem to be pinholes in the vacum elbow near the intake.

Replaced that and it never missed again during idle.

 

Sure - if all obvious vacuum leaks are eliminated and still have the lean condition, points more towards the intake gasket leaks. Ford has even extended the warranty on this to 70K miles, 7 years...or something close to that.

 

Seems to me that you have more than you need to fix the manifold gaskets!
BTW, I concur; it sounds like a vac leak on the manifolds and it's a common problem but fairly straightforward to fix.
All you need to use is the six o-ring gaskets and whicever of the others is the upper manifold gasket.
The timing chain tensioner you can do if you think it's apporpriate, certainly it's worthwhile if you have the manifolds off but not strictly necessary unless you have noise issues from the existing tensioner. It won't make a bit of difference to the lean condition; that's a classic 4.0 manifold gasket issue.