Hi everyone 😀
Just sharing the information I learned about the sticking throttle bodies on the 3.0 V6D engine as I had mine replaced today. It has done 95000 miles.
Since I bought the car in January 2025 it has been running great, no warnings and dpf regenerating as it should, however when doing a diagnostic scan as I like to do for maintenance it was logging code P0234-77 Turbo overboots, commanded position not reachable. It kept reappearing after being cleared.
Lots of research pointed to the throttle body sticking, and if not resolved it was likely to generate warnings and clog the dpf which cannot regenerate if this is showing a fault warning. It also looks like attempts to clean the body do not work.
I had a look and also saw some oil misting where the charge air pipe joins the throttle body.
I spoke to The Jag Specialist at Doncaster who I think will become my new best friends. As soon as I gave them the code they confirmed my suspicions, and suggested a replacement during a while you wait appointment. Helpfully they did not charge for diagnostics as I had given the code.
This morning I visited and first spoke to the head mechanic. He showed me the new Jag throttle body they had waiting and explained that with age and heat cycles the plastic body goes out of round, causing the butterfly valve to stick. He said they had tried cleaning and even reshaping the butterfly valve but they never work long term. The new valve returned to the open position if you manually closed it and then released.
They replaced mine and he brought the old one to show me, it was really clean, not clogged but still the butterfly valve was sticking on the closed position when it should revert to open.
So it's all done, car still runs great as it always did but there is a noticeable improvement in gentle acceleration which is more linear than it was.
Total cost was £407.22 for the part and £80 labour (1 hour), plus VAT £584.66. Time taken was 45 minutes from driving in to driving out. The work included recalibrating the new throttle body on SDD.
I am happy with it and as I am keeping the car have confidence for the next 95k miles or so.
Just sharing as this is a common problem but most information suggests the throttle gets clogged with carbon, and that is not always the case, mine was clean.
Just sharing the information I learned about the sticking throttle bodies on the 3.0 V6D engine as I had mine replaced today. It has done 95000 miles.
Since I bought the car in January 2025 it has been running great, no warnings and dpf regenerating as it should, however when doing a diagnostic scan as I like to do for maintenance it was logging code P0234-77 Turbo overboots, commanded position not reachable. It kept reappearing after being cleared.
Lots of research pointed to the throttle body sticking, and if not resolved it was likely to generate warnings and clog the dpf which cannot regenerate if this is showing a fault warning. It also looks like attempts to clean the body do not work.
I had a look and also saw some oil misting where the charge air pipe joins the throttle body.
I spoke to The Jag Specialist at Doncaster who I think will become my new best friends. As soon as I gave them the code they confirmed my suspicions, and suggested a replacement during a while you wait appointment. Helpfully they did not charge for diagnostics as I had given the code.
This morning I visited and first spoke to the head mechanic. He showed me the new Jag throttle body they had waiting and explained that with age and heat cycles the plastic body goes out of round, causing the butterfly valve to stick. He said they had tried cleaning and even reshaping the butterfly valve but they never work long term. The new valve returned to the open position if you manually closed it and then released.
They replaced mine and he brought the old one to show me, it was really clean, not clogged but still the butterfly valve was sticking on the closed position when it should revert to open.
So it's all done, car still runs great as it always did but there is a noticeable improvement in gentle acceleration which is more linear than it was.
Total cost was £407.22 for the part and £80 labour (1 hour), plus VAT £584.66. Time taken was 45 minutes from driving in to driving out. The work included recalibrating the new throttle body on SDD.
I am happy with it and as I am keeping the car have confidence for the next 95k miles or so.
Just sharing as this is a common problem but most information suggests the throttle gets clogged with carbon, and that is not always the case, mine was clean.