While you're there change the studs, fit them with stud lock (Loctite 270). Use a new gasket and exhaust sealer and secure with new nuts.

When I had my D2 I had a problem getting one of the manifold/down pipe flanges to seal properly as the down pipe flange was off square with the manifold flange. I had to loosen the manifold/head bolts so that the manifold would square up to the down pipe and the joint seal properly, then I retightened the manifold and never had any problem with leaks there again.

 

Far as change the studs, your referring to where the manifold meets the motor or where the y pipe meets the manifold?

 

Manifold/down pipe studs.

There aren't any studs in the head, the manifold is held on with bolts and spacers.

 

Ah ok I got you, so do the studs just unscrew or is it a little more complicated than that? I currently have 1 long stud in the center and the end studs are barely long enough to get a nut on.

 

They should screw out, but may be very tight. A stud remover and a good soak with penetrating oil would make the job easier. The part Nos are LR009704 studs and WYH500060 nuts.

 

Ok guess I'll spray em down real heavy and find out. On the drivers ( the side that sealed perfectly) only has 1 stud and nut, the one on the outside is gone completely I had to cut a bolt out of that to get the old pipe off. So I need to unhook the y pipe and work around it and replace the studs on both sides. Then rehook it back up and see what I got then

 

Bit of bad luck there then, the best way to get the old broken studs out is to have the manifold on the bench, sorry for that bit of bad news. But if you have broken seized studs that need drilled and retapped there's no other way to get at them. In which case you'll also need the exhaust manifold gaskets.

Typical D2 never a dull moment.

 

Well could always be worse I guess, so I guess I could always take the easy way out and try new nuts and lock washers and see if that will hold. If not I'll just have to bite the bullet and take em off.

 

Well finally got around to get new nuts and studs for the manifold to the y pipe and tightened it up. Drove yesterday everything fine but still had code p0150 popped up. Today the truck had difficulty idling at a stop like would be around the 630 range, normal looks to be around 680-700 according to UG. Also the current codes is p0150 and pending codes is p0174 p0300 p0306 p0308. I seem to have fixed the p1174 due to the exhaust leak so that's good. So my next question is could the IACV be not working to cause the low idle and misfires? Also I believe I have a short or bad UG, when I crank the truck the UG may or may not come on and then during driving it will shut off on its on. So I'll plug another tester in after work, so I can see if it's a wire or the UG. Any help would be gladly appreciated

 

Are all of your misfires on even cylinders? What does your UG show for MPH, especially while sitting still?