Sudden loss of low rev torque tdi 130

[caldirun]

For the past few days I have noticed the low rev torque has dropped quite a lot, once over 1400 rpm all seems ok although if I take my foot off the pedal and then back on again it seems to lag a little before the torque comes back.
I have checked group 11 running the turbo test, the max pressure is 1150 mb at 1400 rpm (as a comparison my tdi 100 showed 1285 mb at 1400 rpm) but the vacuum reading on the actuator is 25" Hg so no problem with the vacuum or the N75. The actuator rod seems to be moving its full travel up and down but does not make a clunk when the vacuum pipe is removed with it at its top position. I suspect the vanes are clogged with carbon deposits causing sluggish movement and lack of flow, but why the sudden appearance of the fault?
I did a log of group 11 during a drive this seems to me to support my sluggishness theory.
Any other ideas? and what is the best way to cure?
p.s. Oh joy when I was under the front of the car checking for air leaks I found that both the cv boots had split so more work to do, has anyone removed the drive shafts from a tdi 130, 5 speed without splitting any suspension joints (I have done both on my tdi 100, 5 speed without splitting joints, just wondered if the 130 was any different).

I have tried to upload the .CSV file but get invalid file errors
17566
I have renamed it .txt as .CSV would not upload.

[smithy602179]

i did the nearside cv joint by removing the drive shaft so didn't need to split suspension joints . as for d/s no idea but if you find a way let me know as i need to do my d/s joint soon

[Crasher]

If there are no codes, fit a new genuine dealer supplied Air Mass Meter first and see how it performs.

[caldirun]

If there are no codes, fit a new genuine dealer supplied Air Mass Meter first and see how it performs.

I have tried the AMM/MAF from the tdi 100 (same part number and have 1300 mb of boost at 1400 rpm on this) it made no change to the readings or sluggishness.

[martin1810]

If the fault is below 1500 rpm it can't be the turbo because it doesn't do anything below 1500 rpm. What does a 0 - 400 rpm scan show for MAF. With MAF, never go by single figure, always look at pattern at different rpm.

[fleamoo]

For the past few days I have noticed the low rev torque has dropped quite a lot, once over 1400 rpm all seems ok although if I take my foot off the pedal and then back on again it seems to lag a little before the torque comes back.
I have checked group 11 running the turbo test, the max pressure is 1150 mb at 1400 rpm (as a comparison my tdi 100 showed 1285 mb at 1400 rpm) but the vacuum reading on the actuator is 25" Hg so no problem with the vacuum or the N75. The actuator rod seems to be moving its full travel up and down but does not make a clunk when the vacuum pipe is removed with it at its top position. I suspect the vanes are clogged with carbon deposits causing sluggish movement and lack of flow, but why the sudden appearance of the fault?
I did a log of group 11 during a drive this seems to me to support my sluggishness theory.
Any other ideas? and what is the best way to cure?
p.s. Oh joy when I was under the front of the car checking for air leaks I found that both the cv boots had split so more work to do, has anyone removed the drive shafts from a tdi 130, 5 speed without splitting any suspension joints (I have done both on my tdi 100, 5 speed without splitting joints, just wondered if the 130 was any different).

I have tried to upload the .CSV file but get invalid file errors
17566
I have renamed it .txt as .CSV would not upload.

Did both outer cv boots on my 130 5 sp saloon 53 reg without splitting susp joints, as per your advice. your method transferred between models no prob. If your memory needs refreshing, search "cv boot" followed by "driveshaft gaiter replace" on this forum. cheers, fleamoo

[caldirun]

Did both outer cv boots on my 130 5 sp saloon 53 reg without splitting susp joints, as per your advice. your method transferred between models no prob. If your memory needs refreshing, search "cv boot" followed by "driveshaft gaiter replace" on this forum. cheers, fleamoo
That is a great relief, I had to split the joints on the tdi 100 to replace the arms, it was a nightmare, I was not looking forward to doing it for a couple of rubber boots!

[scotty33]

Can You swap the thrust (MAP) sensor between cars?

[caldirun]

Can You swap the thrust (MAP) sensor between cars?
No they are a different diameter, I bought one off Ebay, as soon as I went over 3000 rpm the car went into limp mode and logged an overboost fault, I am waiting for a refund from the joker who listed it.
I did an Italian tune the other day, it feels better now but it is still slow to pull from below 1400 rpm, the boost required at this engine speed is 1200mb, it takes about 4-5 seconds to get there, this is the lag I can feel, I think a turbo clean is the way to go.

[caldirun]

Did both outer cv boots on my 130 5 sp saloon 53 reg without splitting susp joints, as per your advice. your method transferred between models no prob. If your memory needs refreshing, search "cv boot" followed by "driveshaft gaiter replace" on this forum. cheers, fleamoo
Well if you believe the experts I have just achieved the impossible again, both drive shafts are now on the garage floor and no joints have been split.
That is the tdi 100 and tdi 130 (both 5 speed gearbox) that allow removal of the drive shafts with no splitting of joints!
The trick with the drivers side is to jack the suspension as high as possible then the shaft flange will drop below the gearbox flange, the steering rod end needs to be wound out almost all the way and steering on full lock with the key removed to stop it flying back, to allow the joint to be pulled out. Remove the screw from the brake pipe bracket on the wheel arch and the grommet on the caliper to prevent straining the cables and pipe.

[Crasher]

It may be possible but dropping the two lower arms out is much faster as I can do a CV boot in 3/4 hour and it does not entail having to reset the tracking.

[turpal]

It may be possible but dropping the two lower arms out is much faster as I can do a CV boot in 3/4 hour and it does not entail having to reset the tracking.

Totally agree on this one.Been a while Crasher I`m back in the game again also working on cars for living now.

[caldirun]

It may be possible but dropping the two lower arms out is much faster as I can do a CV boot in 3/4 hour and it does not entail having to reset the tracking.

I don't doubt it crasher, but us mere mortals do not have £30,000 worth of kit to utilize, in my VERY limited experience the lower arms do anything but "drop out"
I do not re-set the tracking, I put it back where it was by painting a line on the locknut and thread, winding the steering end away then using the locknut as a stop to screw it back to.
Having done it both ways (don't knock it till you have tried it, crasher) I am sure this is the better DIY method by far.
I would like a tip on how to strip, thoroughly clean and inspect the CV joint then re-assemble inside that 3/4 of an hour, you have me baffled there.

[Crasher]

£30K, it takes an 18-mm spanner and a hammer!

[fleamoo]

My (also very limited) experience of splitting passat susp joints is that getting them apart isn't too much of a problem, but getting em back together requires some tricky levering and a lot of very bad language.
I would guess that in a professional situation with the car in the air at head height (and considerable experience!) this might be a lot easier. Is that a fair comment, or am i just getting too old for this lark?

[Crasher]

The VAG way is to pull the top bolt out which IN THEORY should be easy if the sodding thing did not rust solid when the car was eight days old and require a £500 tool to get it out without damaging the joints. I must admit that a vehicle lift, transmission jack and two specialist ball joint splitters speed up the work but it can be done without. Each to his own anyway and for once its nice to have a few different ways to do a job that suit different skills and situations, especially as it is such a common task on this widely used platform.

[fleamoo]

The VAG way is to pull the top bolt out which IN THEORY should be easy if the sodding thing did not rust solid when the car was eight days old and require a £500 tool to get it out without damaging the joints. I must admit that a vehicle lift, transmission jack and two specialist ball joint splitters speed up the work but it can be done without. Each to his own anyway and for once its nice to have a few different ways to do a job that suit different skills and situations, especially as it is such a common task on this widely used platform.

Amen to that! Many options as possible.

[caldirun]

Just for the record Crasher you do not split any joints for the passenger side do you? as that is a doddle with steering on full lock, the shaft just falls out, no tracking to worry about.
As regards, the cv joint stripping and cleaning it took me an hour at least to do a good job on both and half a litre of white spirit, do you have any trade secrets for this? (I am assuming the boot is split and that is why it is being changed, not just a preventative maintenance measure :biglaugh: )

[Crasher]

Well we have a 97 A4 TDI in at the moment that needs a nearside outer boot, we will see if that works.

[scotty33]

I found you can get enough lock to disengage the cv, by dropping the track rod end out. The problem is it's pinch bolt is often just as seized as the dreaded top arm pinch bolt..

[Crasher]

Doing the offside wheel bearing the top bolt popped straight out, you never can tell.

[caldirun]

I found you can get enough lock to disengage the cv, by dropping the track rod end out. The problem is it's pinch bolt is often just as seized as the dreaded top arm pinch bolt..
No need to remove the track rod just screw the nut towards the steering rack (assuming that is not rusted!!)

[caldirun]

Back to the original post, I found the quadra seal on the top intercooler hose had gone very soft, I replaced it with an O ring, torque is back at low revs, success at last.

[fleamoo]

Back to the original post, I found the quadra seal on the top intercooler hose had gone very soft, I replaced it with an O ring, torque is back at low revs, success at last.

Well spotted. That's interesting! I've been thinking of replacing the hose seals on mine with a view to possibly improving throttle response and reducing "police siren" type noises from the system.
Any info on o ring sizes and where to get em would be much appreciated.

[caldirun]

Well spotted. That's interesting! I've been thinking of replacing the hose seals on mine with a view to possibly improving throttle response and reducing "police siren" type noises from the system.
Any info on o ring sizes and where to get em would be much appreciated.
I did notice an oil deposit on the box section below the pipe but thought nothing of it as it was not making any noise when boost was on. Changing the seal has improved the low rev torque massively, its like a 3 litre now. I suppose a large leak will make no sound but a small leak will be noisy (open you mouth and exhale, then close you lips and exhale, see!)
Take the quadra seal to a bearing supplier and ask for the nearest O ring above that cross section, it may be best to get a few different ones to get the best fit.

[Ude 65]

Hi caldirin

I've had a similar loss of low revs power, also reducing MPG. Where is this quadra seal?

[caldirun]

Hi caldirin

I've had a similar loss of low revs power, also reducing MPG. Where is this quadra seal?

Righthand side where the upper turbo pipe goes onto the intercooler, the fix lasted for a while but I think it is the retaining clip that is the problem as it is still leaking and I get poor low rev torque. The seal works but the pipe blows away from the socket, it may be wear in the groove that the clip fits into, I will have to design a better retaining system and market it!