Hi All,

I have a 2004 4.2L V6 Heritage and a P0174 code popped up recently. Took it to the dealer after trying to find the problem myself with no luck and found out it was the gaskets on the lower intake manifold that were leaking. I've done some work on my vehicle before and think I can do the job with the right tools and advice. Any tips, pointers, and pictures? I have a Haynes manual to help (they 'exclude' heritage models for some reason but pretty much identical to the models they do talk about from what I can tell).

Thanks in advance.

 

Well I had my uppers/lowers and timing cover gaskets changed by a pro so if you have any doubts save your cash and pay a pro to do it. Since you have to take the upper off anyway might as well replace that one too. Some people say go with OEM gaskets from FORD others Felpro. Also be careful you dont break off a head bolt? I think thats what its called. When they did mine they broke a bolt on the front of the motor, it broke about 10" inside the motor so the had to drill and tap it again. I do minor stuff on my truck like change oil/spark plugs stuff like that but something this involved I let the pros do it. But if you can do it you'll save about $1200. good luck.

 

I just picked up my upper\lower intake gaskets, PCV tube, EGR gaskets, and the new isolator bolts with rubber bushings from the Ford dealership for $190. I'm wussin out and having a buddy who is a mechanic do mine for me. I try to do most of the work on my truck, but I know when I may be in over my head. I am going to watch and hopefully learn when mine get replaced.. Good luck to you if you decide to do them yourself, let us know how you make out.

 

I think 95% of the time this problem is just the isolator bolts (check for the obvious stuff like a cracked vacuum hose or vacuum leak first of course), and to change those you only have to take off the upper cover to the intake plenum. Its not too bad, took me a couple hours and I'm slow. You might as well replace the upper plenum cover gasket too although mine looked fine.

The original isolator bolts have a black rubber boot/gasket that gets hard over time and allows air to be drawn into the vacuum of the intake plenum causing the lean codes (because this extra air in is not measured by the MAF). The new ones should have green boots on them and did the trick for me, I haven't had a single lean code since I did this over the summer (of course now I have a bad hesitation with no codes but I'm positive its unrelated)

 

^^^^^ I replied to you in the "who's reached 100K" thread. Not sure if that's your hesitation issue, but it was for me. Good luck.

 

Yeah I figured this could turn out to be one of those 'doh?!'/Simpsons moments and I should probably let a pro do it. But I figure why not? whats the worse that can happen right?

thanks for the advice guys and I probably will replace the upper gasket while I'm at it.

Will post updates/pics? on progress and hopefully not pictures of my truck being towed to a mechanic.
-J

 

jrm - Do you happen to know the torque specs on these bolts and in what order to retorque them in?

 

puck,

I'm not sure what the torque on those bolts is, they are not carrying much of a load supporting the plastic upper intake so I just made sure they were snug. Don't overtighten them because the lower intake is aluminum and you don't want any stripped threads.

After checking my chilton's manual it looks like you're supposed to do two steps - 53 in-lb and then 89 in-lb. i don't think its terribly important because they're not really holding anything except for some plastic bits so just don't overtighten them.