Jaguar Vanden Plas 2005 4.2L Natural Asp

So I bought this beautiful Seafrost Vanden Plas a few months back and in a few weeks I got this error message and car, as many of you may have already guessed, went into limp mode. It was showing ENGINE SYSTEMS FAULT, DSC NOT AVAILABLE, ABS FAULT, PARKBRAKE FAULT on the LCD. Hooked up my OBD scanner and it only shows one darn code, the P2135 Throttle/Pedal Position Correlation fault code. And there's a generic P1111. Interestingly, the check engine light just goes away after a while. When the problem occurs again, the check engine light lights up again.

I parked the car and started it again and it ran fine. Then after a month or so, this problem came back again. The same process continued and I began noticing that the frequency of these codes started to rise gradually (I stress that word, gradually).

Since the last few days the car is in limp mode almost all the time. I also noticed one thing, that when I put the car in "D" it makes a sudden forward jerk. Is it because of the transmission? Has that got anything to do with this? I see no problems with the transmission. It is butter smooth and shifts are almost unrecognisable to me.

Also, when I car the start after long periods of time, let's say after like 8-9 hours, it runs and drives fine for a while. Also, the problem seems to be occurring at low speeds or while making big turns because I never had this issue on the freeway at high speeds. It's only been in stop-and-go traffic and slow speeds. Now when I start the car, the engine runs fine on "P" but when I shift it to "D" or "N" and then slightly press the gas, the fault comes up back again.

I again want to stress the word gradually. Because the problem has been "creeping" and now it seems it's at its full fledge power.

 

You mean non-generic P1111 (it's a good status code).

Have a look using Search at what others found for P2135 such as https://www.jaguarforums.com/forum/x...ighlight=p2135

But first be 100% sure the battery isn't old / a bit flat.

In terms of the trans it's always worth checking the 2 8mm-hex bolts on the trans side which secure the shift cable aren't loose/missing.

 

You need a new throttle position sensor.

Been there, done that.

 

Yes, I have been struggling for one year to find fault I bought new TB (I cannot to find separate TPS), no errors from exchange.

 

I had a similar experience and it was a dead cell in the battery. Before spending a lot of money have your battery charged and load tested. I hope it's as simple as that. Good luck with it.

 

TPS

 

Thank you guys for the quick response. I forgot to add one critical piece of information. That is that the battery is brand new. Like literally one month old date of manufacture (01/19). I just installed it a few days back.

I ordered a throttle body off eBay that is from a donor XJ for $90. I hope that fixes the issue. I will replace the entire throttle body.

But this makes me wonder. How can such a big car brand make a car literally go below 10mph. What were they even thinking? I mean, if you wanted to keep the throttle steady at 1,200, fine go ahead do that. But why block the transmission from changing the gears? I can only imagine the consequences of this happening on the freeway when you're at 75mph+ in the carpool lane. Imagine losing the throttle. Since I am experienced, I'd immediately shift to Neutral but someone who has absolyrely no knoweldge of this would most likely panick and could potentially cause accident and a chain reaction, possilby himself/herself and other other people behind. Gosh.

Is there a way I can reprogram the ECU to completely disable this potentially fatal problem? Why haven't regulators done anything about it? I'm shocked that there is no TSB for this problem.

The other day I called up Jag dealership near me and told them exactly this same thing and guess what they said: "Well we will start you off with a $200 inspection charge" Well Jaguar you should be happy I haven't sued you for this, duh!

 

The equivalent in older cars was engine cut out so you coasted to a stop, freeway or wherever.

When I had the fault it was not the TPS. I could do a lot more than 10mph - at least 50mph. Cleaned a connector and been fine ever since.

 

Hi Guys

2005 jaguar Vanden Plas 4.2L Naturally Asp Brand New battery

I had posted about my ENGINE SYSTEMS FAULT; DSC NOT AVAILABLE; ABS FAULT error code yesterday.

I was wondering how can I upgrade the firmware of the ECU on my car? Will this be helpful? I saw some place that someone did upgrade the firmware at the dealership and they ran into all sorts of problems later.

 

There hasn't been a software update for the ECU in your car since ~2006

As per your other threads the problem is your Throttle Position Sensor, it needs replacing.

An ECU flash will not solve your problem.

Replace the TPS.

That is all.

 

Maybe will donor TB help. But if it is not a new TB, You can be in the same situation.
TPS is passive component, It is only resistance path and if the track is wiped off, then generates errors.

ECU blocks all components that could destroy the car because it does not know in which position the gas is. And introduces emergency (limp) mode.
As wrote JagV8, now it is better because the car is still (slowly) moving. But 10 mph is curios speed, when I had this error, tha car was moving (did not accelerate) but moving, about 50-80 km/h.
With all due respect, You have different thinking in the USA than in Europe. I do not say better or worse, just another.
There is no reason for TSB, regulators, etc. And suing. It's Your problem that You did not manage the situation and if someone comes across You from behind, then it's his problem, that he did not adapt speed and distance or he did not manage enough to drive the car.
Every component in the car can go wrong and You as the driver are responsible for the safe handling of the situation. The fuel pump may stop functioning as well. Or the brake hose is ruptured because it has been hit by a big stone from the road. Or breaking the fuel hose, because it is old and has a lifetime only 10 years. And …
The idea reprograming ECU is bad, You can destroy Your car. And I think, that it is not possible.

 

You could have just bought the tps for $20 like I did and swap it out. TB is fine.

 

Hi alephzain,

Welcome to the Jaguar Forums!

I have merged both of your threads together so all the information and replies are in one place. Please do not start any additional threads on this topic.

Cheers,

Don

 

UPDATE:

So around 2 weeks days back I swapped my TB with a donor TB that I purchased from eBay for about a total of $90. The TB is amazing. The car's performance has totally changed. It feels totally different now. No more limp mode or that dreaded EMS fault. And the engine feels like it just wants to propel the car ahead. It's pretty strong and transmissions are smooth. I absolutely love to drive her! She's back how she was!

Initially, after the swap, I had a few hiccups like misfire codes and car the shaking. I panicked and thought my problem's just getting worse. But the very next day she started behaving normally. The misfires went away.

I absolutely love her now. I get compliments almost everyday. Let me post a pic here. I highly recommend CarGuy's Wax and Hybrid Wax sealant. It's about $35 investment and truly worth it. I wash regularly and I take good care of her

 

Hi,

Sorry for the question but what's a TB ?

Had all the same stuff happen to me with low battery.

Them Cats do have a tendency to not like humidity and kick You in the ***** for it by drainin the battery once in a while.

 

Throttle Body.