passat tdi problem after cv replacement

[tevion]

Hello everyone ... :1zhelp:

I have a passat 1.9 tdi 2004 100 bhp model.. i recently had a cv joint replaced by my local garage.. the next day whilst driving along at 60 mph the car suddenly felt as if the traction control had come on and the car seemed to hesitate and like a judder felt from the front end ... the yellow triangle light came on on the dash and stayed on . returned to garage and they deleted the code ( they did not tell me the code ) tried car again and now the yellow triangle light flickers as im driving and the car still judders seems to pull left and right then it clears and all ok again . Local garage changed 2 abs sensors on the front and problem still exists . had another code read done and it came up as lateral acceleration sensor . i have now taken it to vw dealer who test drove it and experianced the fault .. all they can come up with is that the rear tyres are bigger than the front ( measured from wheel rim to top of tyre wall ) and that the brake master servo shows a waterline on it and that there must be water in the servo... at a quoted price of £650 for the servo ... the technician told me that it may not be either of these problems its just a start... i am just wondering if anyone has anything to bear on this .. thank you . ( sorry if its a bit long winded )

[towcestervag]

firstly check tyre sizes to see if they are the same ie 205 55 15 front and rear that will illiminate tyres
if lateral acceleration sensor came up on fault code then this may be the fault

[PeterB]

After I had a CV joint replaced my ABS kept cutting in. The garage checked the ABS sensor and found it needed pushing in about a millimetre. It had been dislodged slightly when they were changing the CV joint.

Peter

[tevion]

Thank you for your replies ...

tyre sizes are the same on all 4 wheels the difference in size was measured on the actual wall of the tyre from the rim of the wheel to top of the wall . the ABS sensors have been replaced and both have been tapped in with a soft hammer just case of the small gap which can give a false reading on the sensor.

[Crasher]

Whether the sensors are new or not, that is an ABS sensor speed detection problem, possibly caused by a dirty or damaged impulse ring on the joint. I will add a picture later.

[tevion]

Thank you for your reply ...

Would this ring cause the problems i am experiancing .. the traction cutting in and the car seems to be pulling side to side as if drive is cut from the 1 side of the car

[Crasher]

The ABS is detecting what it thinks is one wheel going faster than the other so it is applying the brakes to slow that wheel down, this will be the opposite side to the one with the problem, if it caused an ABS braking issue it would be the other way around. The CV on the side not being braked needs to come out and be inspected.

http://i222.photobucket.com/albums/dd20/Crasher1964/PST3BCVjointimpulsering.jpg

[tevion]

Thank you Crasher for this reply ..

on viewing this picture .. i have had the drivers side cv replaced also the ring in question was removed as it was damaged and a new one fitted ... problem still persists .. on closer inspection on driving, the car still has the fault it seems as if when the traction cuts in the car pulls to the left first, further driving i have found when turning left under acceleration a clicking can be heard .. do you think that the problem could well be with the near side cv and possibly that ring also ... i would rather change the cv joint if it starting to let go rather than the expense of what the dealership has said.

[Crasher]

It will be one of the front sensors or rings, if one side is new it must be the other.

[tevion]

Thank you Crasher

I have just booked the car into garage to have left hand side cv joint replaced .. mechanic at garage put car on ramp and looked under it at the cv's , the new one fitted on drivers side , boot has split already and oil / grease is coming from it.. so he says he will check both sides and see what's going on... he does confirm that the ring as you suggested could well be the problem . Car is booked in for tuesday A.M .. will let you know what happens after that..

Thank you all for your time and help its very much appreciated.

[Crasher]

I only fit genuine CV boot kits, aftermarket ones are rubbish.

[tevion]

I didnt get the chance to take the car to the garage as i needed it for work but hopefully car will be in the garage thursday .

[cazyp]

Be aware that the ring may have been damaged when the garage fitted the new cv joint before you agree to £££££ bills..
Infact, given that it started when you got your car back its very likely..

[tevion]

hi .. Crasher has already explained about this ring .. i have asked the mechanic who is doing the job if he will infact check this ring before condemning the cv for a new unit. I just hope its this ring and not another cv needed..

many thanks.

[Crasher]

The impulse ring is not available as a spare part, if the ring is damaged the joint has to be replaced.

[tevion]

ok guys .. just had a call from the garage ... the mechanic has taken out both cv joints and inspected them the impulse ring on both are good , he has cleaned them off and fitted them back .. the problem is still there .. he says it happens at between 58 - 60 mph .. he is now going to try and investigate the error code that came up on it previously .. but says without a code actually in memory we have to wait untill it comes back on .. the code was 01423 ( G200 ) .

[scotty33]

I believe you can observe the function of the ABS/ESP sensors in Vag com, it would be useful to see excactly what is happening with each sensor at the speed they go belly up?

code: http://wiki.ross-tech.com/wiki/index.php/01423

[Crasher]

Then as Scotty says, he needs to study the measuring blocks to see the wheel speed inputs to see what is happening. Mind you, some of those ECU’s kick you out of MVB’s above about 10mph, very inconvenient.

[tevion]

Have asked the garage if they could check the sensors whilst the car is travelling ,, mechanic explained that he cant do it at that speed apparently it wont let him ?? but all seems fine at very slow speeds ( problem ocurrs at 50 - 60mph ) he is at a loss with it , but says that to save money on cost of repair and hair pulling .. to try a lateral sensor from another car if possible and see what happens ... i am at a loss with this fault .. so still open to any info .. thanks guys ..

[caldirun]

After I had a CV joint replaced my ABS kept cutting in. The garage checked the ABS sensor and found it needed pushing in about a millimetre. It had been dislodged slightly when they were changing the CV joint.

Peter
They must have hit the sensor with the cv joint when removing it or replacing it to move it 1 mm. The sensors should be removed before removing the cv joints, change both sensors, they may have torched the wiring when splitting the joints. If they hit the sensor with a soft hammer, they must be a bit soft in the head!

[Crasher]

Yes that can be a problem with certain ABS ECU’s, the ECU kicks you out at anything above walking pace, very very annoying when trying to diagnose faults.

[scotty33]

Try finding a garage with an oscilloscope?:

http://www.sjmautotechnik.com/trouble_shooting/misc_waveform.html

[Crasher]

Yes an oscilloscope is the way to go but very difficult and time consuming to set up to road test. Even doing it on the ramp with the wheels off the floor is time consuming. It would be easier using a dual trace on the front wheels so the sensors could be observed side by side. It is extremely irritating that the system will not communicate when moving above walking pace.

[scotty33]

All I can say is : the CV's have (allegedly*) been checked for the condition of the tone rings, the ABS sensors have (allegedly*) been replaced.
Short of changing/checking these parts again, I don't see another way forward?
The scope should not find anything wrong, but if Crasher says it is an ABS sensor problem then it surely will be..

* please excuse my cynicism, it runs riot when a garage appears to have caused a problem when carrying out routine work.

[Crasher]

Garages/mechanics can get a little upset with comments like that. Yesterday a customer accused us of not changing the inner CV joint boots we had billed him for on his automatic Sharan. After getting a little stressed with him and insisting that we had changed them as I had been directly involved in getting the job done he said that he could see no sign of the job being done inside the tailgate… :rolleyes: Mind you this is the same chap who had called us up whilst we were doing the job and asked us to get some keys out of the car safe, the key being on the key ring. We searched high and low for this safe and eventually called him back to be pointed in the right direction. He told us it was on the left of the car and so we went back and had another look, we could not find any sign of a safe. Eventually we established it was the glove box! :aargh4:

[scotty33]

Garages/mechanics can get a little upset with comments like that.

Sorry, I'm not tarring all with the same brush. I would trust C&R to not make mistakes!
It seems to me this particular problem stems from the work that was carried out, which in my book makes the garage liable? They claim to have checked the CV tone rings and changed the ABS sensors. If these are ok/new and the sensor gaps are correct there cannot be a problem with these parts. Yet by your own word, there is an ABS sensor problem.

I hope there is an innocent explanation, or at least a result for the owner, this seems like a can of worms which is he is a victim of, as things stand?:beerchug:

[Crasher]

Ohh I make mistakes, I am only human, well sort of.

It does sound like a sensor problem but remote diagnosis from posts is not at all easy, in fact this one would be difficult if I had the car.

[tevion]

Thank you for all your help and pointers ... here we go again ... right .. the mechanic is satisfied both cv's are good .. the abs sensors are new from VW .. he has now run the car with the ESP button pressed and the fault is still there .. he has now unplugged the sensor that sits under the rear seat and the fault has dissapeared .. plugged the sensor back in and the fault returned .. the sensor has part number 8E0 907 637A ZSB Duosensor ESP .. ( yaw ) sensor .. so is trying same part from a donor car , i'm hoping this will do the trick .. do you think this part could cause the problems i have been experiancing ??

[Crasher]

That is the combi yaw sensor, usually if these are playing up they come up as a fault code. I am glad he is able to substitute one as fitting a new one as a guess would cause a near £600 dent in your wallet.

[tevion]

the yaw sensor has been donated from a scrap vehicle same year and model and once fitted it made the car totally undrivable .. having priced the part from vw it was a staggering £567.00 also priced it at euro parts and a little cheaper at £360.00 + vat .. would there be a difference in quality / performance of the part coming from euro parts ?? .. also i would like to know if i were to not replace the sensor as the car ran fine without it , so to run the car without it ,, would this be recomended or foolish , will the car be safe , is the esp needed ,, what problems would come of this ? Thank you very much

[Crasher]

If you had an accident and the insurance company found that you had disabled the ESP they may get grumpy.

If the sensor from ECP is a Bosch 0 265 005 252, then that is fine.

Your chap does know about calibrating them doesn’t he?

[tevion]

the sensor is a bosch 0 265 005 245 .. so that stuffs that idea. As for if he knows how to calibrate them i am not sure , with the 2nd hand part 2 error codes were logged straight away lateral sensor and yaw sensor and car was very unstable undrivable to be precise , with my sensor fitted fault occurs at between 58 - 60 mph and no codes logged but esp light flickers like as if car is wheel spinning and traction / brakes come on and pulls car to the side , the light does not stay on long enough to register a code .

[tevion]

trying to post a pic of said sensor , just to make sure its correct .

[cazyp]

A fellow taxi driver got one from an A4 at a scrap yard about 3 weeks ago..
Worth a hunt around under the seats.. ;)

[Crasher]

I meant the new sensor has to be Bosch number 0 265 005 252, Bosch number 0 265 005 245 is not even listed so it must be an old number. Yes it also fits various Audi’s.

[tevion]

completely at a loss now, maybe i will just drive the car as it is untill something gives a code or even breaks . Thank you Crasher and everyone else for all your help and input into this problem. If i ever get it resolved i will be sure to come back and let you all know .

[tevion]

Good news guys :biglaugh: .. the mechanic was not happy that he could not fix the problem so and after some head scratching and letting him view this thread more head scratching .. and both cv's out again and more checking , after very close inspection of the impulse ring ... the impulse ring is bigger than the other ( the new cv ) so he ordered a new cv joint .. fitted .. and car is running normally , no more juddering or pulling to the side . How or why the ring is bigger he has no idea but has returned it to his supplier .. Crasher you were spot on with your diagnosis about the fault being with the impulse ring ,, thank you very much indeed :beerchug: also thank you to evryone else who contributed .

[scotty33]

Good result for you - eventually, and egg on face for me!:o seems I pointed the finger at wrong sector of the motor trade.
Sounds like a very unusual problem but totally related to the work done. At least the mechanic came up with the goods in the end:beerchug:

[Crasher]

I would be interested in the make and exact part number of the offending CV if that is possible, I would like to look into this deeper. If you could find this out and PM the info to me together with your cars reg number I would very much appreciate it.