I've been going through and trying to tighten bolts and find the air leak from this other thread (https://landroverforums.com/forum/lr...ng-post-110785) and while replacing the EGR gasket to the TB, I noticed the top (closer to the rear) bolt very loose. Like 3 or 4 easy turns loose to snug. The lower one (closest to the grill) was like 3/4 of a turn to snug. Now they are both tight but don't seem to stop and lock all the way in. I'm not reefing on it fully either so I don't break anything but I assume the major looseness described above is bad - why have a loose bolt in the engine?

Can someone confirm that sounds right please?

If I remove them completely is this where I can do some EGR cleaning after removing the electrical connection or is it the lower section which looks like cast metal the part to clean? I have the lower gasket to replace when I can loosen the upside down bolts but I'm not yet sure that's necessary unless I need to clean them.

 

So you did not try to tighten them? Or are they stripped? For cleaning there should be two long bolts that go in from the side too. The upper most bolts I don't believe will allow removal as the inner parts will prevent removal. Really those uppers should never need to be touched for any sorta service. But once you remove the EGR, I guess ya could to help clean it up.Also know that between the main body and throttle body plenum there is another small metal gasket. I tend to coast these with THIN amounts of high temp gasket maker. You need very, very little. Same goes for the main throttle body housing to plenum if I reuse em, I tend to replace them now each time.

 

Good info on the gasket sealant. Both the main TB basket (big square one) and the ERG to TB gasket (small one with clips) are new but have no sealant on them.

The old gaskets that came out were definitely worn.

As for the top bolts. They are now very tight and if I apply almost max force to turn them, then they will go a little. I’m concerned about stripping it so stopped because it’s much better than it was!!

Just wasn’t sure if that part had any reason to have the bolts removed for a past service (recent thermostat housing replacement) or if I should clean it as some preventative maintenance.

The side facing bolts were tight, are tight with the new gasket.

The upside down / bottom screws have not been touched and I couldn’t break them loose so I did not change the gasket there.

Could the found looseness of the top bolts contribute to an air leak and lean codes?

 

Yes, if those top bolts were loose enough to cause play, then there would be a leak.

 

Thanks for confirming what I was thinking. The top bolt was loose enough to twist with my fingers so yeah, there’s that.

Hopefully that fixes the lean code.

 

2nd on the gasket sealer. I applied a small amount with a Q-tip and it solved my leak.