I'm no expert about this, but it's my understanding from reading this forum the last 10+ years and looking into it elsewhere that cold temps are not the only factor that could theoretically cause icing in the throttle body that would cause the throttle to stick open. Humidity also plays a role. Look up "venturi affect".

Proponents of keeping the TBH operational like to say that the LR engineers wouldn't have included the TBH if it wasn't prudent to do so based on the engineering. But it's also possible that the LR Legal Department is who decided it was prudent.

I also look at the TBH design and wonder whether or not it would really be effective in the scenarios that could lead to throttle icing.

Whatever the facts and history, I bypassed the TBH in my truck years ago by simply blocking the little hoses running to it and from it with small bolts held in place by the hose clamps.

 

All the Throttle Bodies which customers claimed stuck on them on the highway that I got my hands on = DIRTY or they had a throttle cable that looked like it belonged onboard the RMS Titanic (early D2's had a recall on the Throttle Cable actually). Several years ago I got my hands on one that stuck (during a massive Blizzard in north TX) . I swapped out the entire TB and got my friend/customer on their way. I tossed the TB into my spare parts bin, but curiosity got the better of me so I grabbed it and inspected it. All the springs were intact, it wasn't rusty, it wasn't the last revision TB ever put on a D2/P38, but it wasn't the first either. It was dirty, but nothing like I'd seen before. Move the TB plate by the linkage, let go, and bingo stuck open. I tore it all apart at that point, cleaned the TB plate itself with a scotchbrite pad (very outside edge), and I removed the small wear mark inside the TB from where the TB Plate rest. Put it all back together exactly how it came apart, and it no longer stuck open.

On other vehicles I've owned people always got their TB's ported/polished. Never heard of anyone with a LR doing it, but I now take the time to clean mine at least once a year. Zero issues, and I even removed the TBH plates on both my D1's which is a bit more involved, but it helped free up some space around the TB, and one less hose to worry about (noticed OEM TBH gaskets were seeping on both D1's when I did HG jobs).

 

Mine was leaking and I deleted it. So far no problems, but I am not very often in the cold. I thought about installing an electric heater element, which can be switched on/off from the cabin when it is really needed.

 

Deleted on both of mine.

 

The exhaust manifold is directly below it & temps from those at idle are 425F and heat rises so 1ft away the aluminum intake sits. There is NO WAY you can have ICE & 425F that close together. I understand the whole venturi effect, but that's mostly on airplanes in totally different conditions with a lot more wind speed & much colder intake air temps.

I'll take my chances as is and rather know my LR's aren't slowly bleeding to death vs the 1 in 1,000,000,000 chance it could stick.

 

Like I said, the legal department prevailed.

 

Yep CYA is a way of life these days. Glad I grew up in the late 70's & 80's!!! One hell of a childhood, kids these days will one day look up from their cell phones & look in the mirror & they'll be 75 years old hahaha what a waste!!

 

Mine doesn't leak, so last year I put a valve (pressure and temperature rated) in it. Closed for summer, open for winter. So far so good.

 

D1's dont have it and there is no cold weather start issues

 

D1 3.9/4.0 do have TBH it's a much better design, but age can catch up them as well. It's like 2 times the size of a D2/P38 Bosch setup.