I took my 85 Eldo Touring coupe in for a simple front end alignment and flush and fill and they told me I had a blowed intake manifold gasket, so I gave them the OK to just replace it, then they called me back and said one of the iol passages on the PS head is caked with carbon deposits, and the bhead needs to come off to be boiled, I told them no. Anybody know of a chemical that will break this down? I don't have the $1100.00 or so to have this done. This is the 4.1L with 62K miles on it.
Steve

 

If intake is still off a good carb cleaner and pick tool / awl / wire coat hanger made into a longer type pick tool.And a lot of patenice, carbon can be dug out and passages cleared. I don't think any chemical will work if engine is back together.

 

can you clarify?
I can guess but this makes little sense to me.

At any case, carb cleaner or Sea Foam dissolve carbon deposits.
There is a thread on the Sea Foam.

 

4.1 AND EARLY 4.5 Had concerns with oil drain back clogging and holding oil in valve cover: not letting return to valley as it travelled back to pan. Oil returnpassages arevery close to head bolts which may have had something to do with the condition. the head was redesigned to eliminate problem by the 89 model year. "desludging" was a common part of intake gasket replacement thru out the 80s mostly on the HT 4100 engine