Hi
Hoping you all might be able to help.
My LR3 2.7 TDV6 throttle body failed on me this weekend. The side of the "plastic" composite housing has melted, from inside to out (from what I can tell). Aside from the usual coating of carbon build up from the exhaust recirculation, there is a bunch of hard brown "stuff" on the inside on the same wall where the bubbling out happened.
I have included two images, one of the outside of the throttle body showing the bubbling out, and the other the brown stuff.
Questions for the team are;
- has anyone seen brown stuff like this before?
- do you agree the damage is from inside out?
- if it is from inside to out, what could possibly heat to melting temp of housing meant to take 100+ C degrees? and how can I avoid in the future?
There are couple of recent, 6 months, things that have happened. First is the car has been intermittently sluggish. I thought it might be torque converter so I changed the seals and put new fluid in. I also changed the intercooler hoses, yes there was a split an inch long at the top of the long hose. I also cleaned the intercooler out of oil, yes there is/was some oil evident in the intercooler. I have cleaned the MAP and MAF sensors multiple times.
Up until this throttle body failure, the car idles well, only code is a EGR valve left (passenger) side that has been there for 5 years (yes I have a new valve ready to go in!).
Any advice hugely appreciated!
Thank you in advance,
Chris

Brown "stuff" on the same wall as the bubbled plastic

Bubbles in the plastic wall of the throttle body

 

First off i don't know country you are in, update your location, but there were no diesel variants sold in North America so you would be better off in a UK/AU forum or the facebook group.
Lucky for you there are 1 or 2 with TDV6 engines here including me, i would say you have had an EGR valve failure which has caused hot exhaust gas to flood the intake and melting the throttle body.
Once you fit the new EGR valve i would blank them so it doesn't happen again, this could have been prevented if you investigated it when you first got the DTC for the EGR.

 

Thank you!
I didn't know the intermittent EGR valve failing might send extra hot gas into the throttle body!
I will replace the EGR valve immediately!
I did replace the EGR valve once, but it was a aftermarket one and it didn't fix the intermittent fault. I have a genuine one. It is a hard job to do, no excuse, but I have stalled replacing because of that! My fault completely!
Thank you again!

 

Access is tight but if you remove the battery compartment pieces you will get better access, what is your location ?

 

I think I found what happened!
I pulled the coolant cross over pipe off and there was no coolant! Even though the tank is at level. Seems there has been an air pocket or drop in coolant level I hadn't noticed.
My thinking is that the coolant level has dropped in the EGR cooler to the point where the recirculating exhaust wasn't being cooled. Hence extra hot gas into the throttle body and melting it.
Taught me a lesson! I need to be much more careful with coolant levels.
Thanks for all your help! Your advice pointed me in the right direction.

 

I think we can close this one out unless something else happens!
Appreciate the help!

 

I would still replace the EGR valve.