Intermittent boost cut?
#21
Hey there - I am having what might be the same issue.
I picked up the car this weekend, and put 500 miles on it in just over 2 days. However after that, I noticed a very different change in boost performance, when in dynamic mode, where the throttle is quite laggy when accelerating 50-100% from 1000-1500 rpm. It accelerates sure but it's no longer the huge torque and kick in the seat... Torque is great though if the car is already at 4000+ RPM, e.g. after downshifting a couple gears.
Maybe another blue duck?
I'm taking it to the dealer in a few days.
Can you list out exactly what the dealer did on your invoice please? Thanks a lot!
I picked up the car this weekend, and put 500 miles on it in just over 2 days. However after that, I noticed a very different change in boost performance, when in dynamic mode, where the throttle is quite laggy when accelerating 50-100% from 1000-1500 rpm. It accelerates sure but it's no longer the huge torque and kick in the seat... Torque is great though if the car is already at 4000+ RPM, e.g. after downshifting a couple gears.
Maybe another blue duck?
I'm taking it to the dealer in a few days.
Can you list out exactly what the dealer did on your invoice please? Thanks a lot!
The following users liked this post:
pistol (02-18-2016)
#22
"SDD Session logged, related code P132b-77 logged. Inspected supercharger boost control actuator. Datalogged actuator feedback. Removed supercharger upper housing and inspected boost control butterfly stop and operation. Accessed engine control module and inline harness connectors in boost actuator circuit. Pindrag test all nodes and traced to receded pin in ECM connector. Released retainer and fully seated pin. Cleared memory and drivecycled. Retested, OK."
And I can confirm that after 800 miles, it is OK.
And I can confirm that after 800 miles, it is OK.
For me it was a beast right off the lot, lots low and high end torque. Now the low end torque is gone most of the times. I still get the sound, the revving is there, but there's little torque to match and no kick in the seat. It's a pretty noticeable difference, especially as I really played with the car for the first 500 miles so I am quite familiar with its performance.
#23
Thank you very much - I've added this to the online service appointment notes, hopefully it helps them track it down for me.
Thanks for the datapoint. I really hope that's not true. I feared I'd ask them to do a test drive with another one, and find one with the same issue. Your case would suggest that's entirely possible.
For me it was a beast right off the lot, lots low and high end torque. Now the low end torque is gone most of the times. I still get the sound, the revving is there, but there's little torque to match and no kick in the seat. It's a pretty noticeable difference, especially as I really played with the car for the first 500 miles so I am quite familiar with its performance.
Thanks for the datapoint. I really hope that's not true. I feared I'd ask them to do a test drive with another one, and find one with the same issue. Your case would suggest that's entirely possible.
For me it was a beast right off the lot, lots low and high end torque. Now the low end torque is gone most of the times. I still get the sound, the revving is there, but there's little torque to match and no kick in the seat. It's a pretty noticeable difference, especially as I really played with the car for the first 500 miles so I am quite familiar with its performance.
Additionally, if you log the AFR on the stock file on a warm day or on the dyno, you will see the top end of the range 5000-6500 go extremely rich to cool cylinders and tame detonation. You can see this happen in a on my dynos, tuned or stock. The Vmax tune exhibits less of this behavior and nearly none immediately after flashing.
I'm not sure what Jag is doing with the TCU logic on the AWD as well to help prevent high torque destruction and how this all plays together with the ECU.
I invite anyone to jump in on this discussion btw, please share info/Knowledge.
The following users liked this post:
pistol (02-19-2016)
Thread
Thread Starter
Forum
Replies
Last Post
philwarner
XJ XJ6 / XJ8 / XJR ( X350 & X358 )
0
02-02-2016 10:54 AM
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)