I tried cleaning the mass air flow sensor twice, looked for a leak between the butterfly and the MAF, idle smoothes out when I spray carb cleaner under intake plenum on passenger side. Could it be a hose under there or the yellow oval plenum gaskets? maybe MAF bad?

 

Hope the following link helps you out.

Jaguar vacuum leak p0171 p0174 s-type 3.0 <-- THANK YOU Gus!

 

Thanks, this is the area I sprayed the carb spray into and the idle improved while doing it. I already replaced the spark plugs and coils so I've been down in there before and was afraid I'd be back this time.
Oh well and thanks again for the great info!

 

I would replace the upper and lower intake gaskets as well.

 

Good job Rick.

 

An actual stall on that era & engine will almost always be an air leak and again almost always the PCV hose elbow. Yeah.... you're gonna be in there again!

 

Got it back together last night and drove it around the block. No more vacuum leaks/codes, but now I have a leaking injector at the rail. I bought new o-rings but the parts place only had 2 packs of 4, so I just replaced the bottoms, (gambled and lost). It's raining today so tomorrow I'll get back in there to replace $5 worth of parts...

 

At least you did it by yourself and you're almost there. Good job!

 

Kudos to you!

 

I changed the injector o-rings the next day and it runs like a top.
No more leaking oil onto the right exhaust manifold (stinking air conditioner smell) either as I took the suggestion and changed the Intake manifold tuning valve o-rings and cabin air filter too.

 

Congrats, glad we could help!