V6 auto fault, please help me..

Hi guys, bought a nive V6 freelander a while ago to use as our towing car. Its an automatic and it had a fault for some time now that I cant get solved.

Syptoms
- idle cold or hot varies when you come to a stop, sometimes 800rpm other time 1200 rpm and then you have to hold it on the brakes hard to stop it moving.
-seems slow to accelerate
-MPG seems really bad, worse than normal
-when you press the accelerator down fully the gearbox waits for a while then slams the gear in, very abrupt and not right. From then on it goes very well.
-slow to drop down a gear as you come to a stop.
-revs dont seem to fall when not accelerating unlike any other auto I have ever driven.
-when accelerating gradually they is some shudder / shake sometimes...

Ok to there we are, I have let Landrover main agent check it and they say there are no fault codes coming up, fluid level is bang on and clean. If you drive the car in sport/manual mode, there are NO PROBLEMS AT ALL ...... its only when in auto mode.


After a lot of searching around, could a faulty Throttle posistion sensor cause all these faults??? Please help me, I cant afford to keep throwing money at it and its a good car overall....

thanks to everyone in advance for your feedback.

Oly

piooly said:

Hi guys, bought a nive V6 freelander a while ago to use as our towing car. Its an automatic and it had a fault for some time now that I cant get solved.

Syptoms
- idle cold or hot varies when you come to a stop, sometimes 800rpm other time 1200 rpm and then you have to hold it on the brakes hard to stop it moving. When you stop for nore than a few seconds, put it into neutral or park. If you leave it in drive or reverse then your still loading the engine, wearing out your auto.
-seems slow to accelerate
-MPG seems really bad, worse than normal. What do you get? 18mpg around residentual streets and A roads at 40mph for mine. 28mpg at a steady 60mph on the motorway.
-when you press the accelerator down fully the gearbox waits for a while will be about a second then slams the gear in this is expected as your asking for max power and that aint good for an auto, very abrupt and not right. From then on it goes very well.
-slow to drop down a gear as you come to a stop.
-revs dont seem to fall when not accelerating unlike any other auto I have ever driven. when you say fall, do you mean when it changes up after accelerating?
-when accelerating gradually they is some shudder / shake sometimes... between all gears or just some?

Ok to there we are, I have let Landrover main agent check it and they say there are no fault codes coming up, fluid level is bang on and clean. If you drive the car in sport/manual mode, there are NO PROBLEMS AT ALL ...... its only when in auto mode. Sport mode is still in auto mode, but it will hold the gears longer for faster acceleration. Hence revs will rise higher before fear changes.

After a lot of searching around, could a faulty Throttle posistion sensor cause all these faults??? Please help me, I cant afford to keep throwing money at it and its a good car overall....

thanks to everyone in advance for your feedback.

Oly

Click to expand...

Some comments in red above. An auto fluid change can do wonders for the Jatco auto in the Freelander 1. Also did the garage do a resistance check to see if all sensors measure within the limits? Does 5th gear select and work? Does reverse gear select and work?

Syptoms
- idle cold or hot varies when you come to a stop, sometimes 800rpm other time 1200 rpm and then you have to hold it on the brakes hard to stop it moving. When you stop for nore than a few seconds, put it into neutral or park. If you leave it in drive or reverse then your still loading the engine, wearing out your auto.yeah I know this but when you stop at a junction the revs should drop to idle 800rpm ish, this sometimes happens but other times it stay high at 1200 so as you come to a stop you have to really stand on the brakes to hold the car from rolling forward. This is not normal, the revs should always fall back to 800 or so.....
-seems slow to accelerate
-MPG seems really bad, worse than normal. What do you get? 18mpg around residentual streets and A roads at 40mph for mine. 28mpg at a steady 60mph on the motorway. best mpg I have ever got was 24mpg on the motorway at 65mph the whole journey, I know this engine is bad for that but that is still a bit low. At the moment the MPG is the last of my worries, its the way the gearbox slams the gear in thats wrong.
-when you press the accelerator down fully the gearbox waits for a while will be about a second then slams the gear in this is expected as your asking for max power and that aint good for an auto, very abrupt and not right. From then on it goes very well.the wait can be 2 to 3 seconds and when I say slam its as if someone has just driven in to the back of the car!!!!!! I'm not talking the old school auto gear change tardyness, this is violent....
-when accelerating gradually they is some shudder / shake sometimes... between all gears or just some? usually in the lower gears, 1st, 2nd, 3rd

On the whole the car is also too keen to get into 4th and 5th before it should do meaning the engine is laubouring more than it should do.

Some years ago I suffered with the same bang and shnut as if someone had crashed into me, but not the other faults. Gear change became pronounced, so you could feel it more than usual. Only happened to mine when warm. Often noticed it after a short trip when restarting. The fault was caused by low auto oil, due to a leak. Didn’t know it were leaking.

Anyways, while going through the fix problems and eventually a replacement auto as all the main case seals blowed in the end, I learnt the method of test from the main dealer. First thing to do is check the auto oil level is correct. There’s a specific way to do this, at 35 to 45 degrees. There’s a long fred on ere on how to do it, wiv instruction un pic’s. MAKE SURE YOU GET THE COLLECT BOLT as undoing the wrong one will cause you more hassel. There’s often arguments on this in ere, but the best way to know what’s what is to leave the car over night on a level surface to cool down, then start the procedure. If you don’t then you don’t know if the internal temp is different to what you can measure via the filler plug. Next is a resistance check on the sensors and solenoids to see they measure within spec.

An easy first check is to make sure the barrel connectors which hold all the electrical connections to the auto are secure. If they come apart you get gear shift problems, with a bang/shunt sometimes (well I did). This fault normally has F4 flashing on the dash but I’ve had it wivout. These are the connectors you use to measure the resistances measured above. Located above your auto. Look down by the battery at the auto and you’ll find them. If none of this shows a fault then there’s a fault inside which can occur where something cracks. Said to be a common problem but there int many eggsamples of it on the web… Someone on ere had that fault before and posted about it when they had it fixed.

The shifting up early may be your Freelander realising there’s a fault and it shifts to 4th as a “get me home” limp mode. The 800 switching to 1200 rev thing is something I’ve had before too and that was caused by the barrel connectors being loose. Auto's are difficult to fault find so the above steps will start you off.

A common problem is to remove the wrong nut thinking it is the level/filler plug. It's not. It's holding the reverse brake band (or something to do wiv it) in place and the auto needs taken apart to put back. Hence you lose reverse gear if this happens.

http://www.youtube.com/watch?v=VTmdkDuKZ6A

ere's the connectors:


DSC01080 PnqqrjE

P4051811 MNkPShY

right thanks for that. I shall first test the connectors for the correct resistance. Took some time to find out what they should be but I have found that now so I will do some investigation. It really annoys me how a main agent cant be bothered to check stuff like this. They just checked the fluid level etc and charge me £60 for the privilage......

I am happy do do any kind of work on cars but auto boxes is where I need help, so we shall see.

ok been out to try a few things. Checked ohms on everything and to be fair they were all above the values they should be but I think there may be an error with my tester maybe, etc and then just before I went to test drive. I reset the TPS. Drove the car and everything was cured going very well. Warmed the car up, still fine so decided to turn around and drive home. Then the problem came back, floor the accelerator and bam, its as if the car cant decide what gear to in then it decides and drops down 2 gears instead of 1 and thus the violent gear change.

I pull over and reset the TPS, everything is fine again...... so I drive home.

Could the TPS be doing all this? glad if it is as its not too expensive to change. I might try this a few times and if thats it then I will order a new one....

Yes, I think so. Some extracts from the rave disk:

Sensors
The EAT ECU [auto computer] sets correct gear change scheduling using three speed signal inputs: intermediate speed, turbine speed and vehicle speed in conjunction with a throttle position signal from the ECM [engine computer].

Engine Speed and Throttle Monitoring
The ECM constantly supplies the EAT ECU with information on engine speed and throttle angle through messages on the CAN bus. This information is used by the EAT ECU to calculate the correct timing of gear changes.

If the messages are not received from the ECM, the EAT ECU will implement a back-up strategy to protect the gearbox from damage, whilst allowing the vehicle to be driven.
In the event of an engine speed signal failure any of the following symptoms may be observed:

Decrease in fuel economy
Increase in engine emissions.

In the event of a throttle position signal failure, any of the following symptoms may be observed:

Harsh gear changes
No kickdown
Torque reduction request inhibited.




Normally we get physical failures with the Jatco auto, or electrical connector fail. Gears changing late due to stuck values, or gear selection poor due to sensors being out of tolerance, telling the “process” to do things at the wrong time.

If your problem alters when playing with the TPS then you may have found your fault. It surprises me there weren’t any codes in the computer. This would be in the engine computer, as opposed to the auto computer. The engine computer will monitor the TPS and advise the auto computer of the value (driver demand) and the auto computer will orchestrate it’s magic to carry out what’s required, based on info given and I guess also the measurements it takes from the auto. Bit like tratter boys telling us Freelanders are crap, when they int. We’d all make the mistake of selling up un buying a tratter, only to find they is worse. All because we were given the wrong signal. TPS looks cheap so if it’s playing up, then possibly a cheap/quick first try to fix the fault.

According to microcat this is mine:

XKB100150L THROTTLE POSITION SWITCH PETROL | shop | www.lrseries.com | L. R. Series

Any rough idle at all?

my v6 head the injector in cylinder 3 stuck open... Obviously leading to bad idle and bad fuel consumption... Also lead to pour gear changes because the motor had lost all balls so it had to drop 2 to get any momentum.

also worth checking vacuum lines to sniff out that idle spike.

it has had in the past and still happens occasionally a rough idle. When the car is going like this it does feel like ' come on whats the car doing, get a move on'....

I am going to source a new TPS. Unfortunately the one you suggested HIPPO is the wrong one for my engine. The one I need looks identical to the type used on a rover 1.8 k series engine. Dont know if it is the same part so I will search the web a bit. What you have said form the RAVE disk makes sense and it would explain why when resetting the TPS the problem is resolved for a short time. If an injector was stuck open the car would not perform well in sport/maunal mode and it does so I think that irons that out..?

Vacumm lines may be worth a look so I will check them. How do you check them though. All pipes look in good nick, no perished parts but spose it could be hard to detect..