Poorly PD130... Your thoughts?

T. Spark

Guest
OK dokie, I have a poorly TDi (again! ggrr)

Problems

1. Gear box wont select gears straight away, its 'clunky' and takes literally seconds to change into any gear.

2. At low rpm (1k-2k) when setting off if I give the car some gas aswell, it chudder's really badly until I rev it more to 2.2k+

3. The turbo spools late, starts kicking in at 2.1k and below 2k its as flat as a fart.

4. Its down on power, it only got 160bhp on the RR.

Now the torque figure is fine, at 295lb.ft and the graph for both the power and torque are normal, its simply 20bhp down?!

All these problems seems to have arrised after my new exhaust, which is 2.5 all the way down, no nothing's and its abit loud :) But downpipe etc is all standard.

Ideas?

So far, ive heard no back pressure due to new exhaust, which would explain the lack of power, and no turbo til 2.2kish but I cant see how that would include the gearbox problem, and judder.

Or flywheel is knackered, which would explain judder maybe? And gearbox selection problems maybe? But would this problem mean 20bhp down, but perfect RR graph? Wouldnt the torque be down?

The major one ive heard is a Injector has gone!? Really? Wouldnt that also have taken the torque down aswell?

Ran a quick vag-com check and no errors, ran some logs and everything seems normal, boost etc etc

Ideas?!

Thanks you diesel boffs!
 

maxcars1

Full Member
Nov 9, 2004
735
0
If you gone 25" cat back but left the dp then i wouldnt have thought this would cause the issue. I would do some logs to check boost and MAF initially. With regards to the gear selection/ judder, it could be anything. If nothings been done to the settings on the gear selectors, then i would have thought its either in the clutch area or the clutch slave cylinder. Th einjector can be checked in vag com to, but when i had one go it was well noticeable - it didnt like 4th/5th gears below 2k revs
 

T. Spark

Guest
Cheers guys,

When its on tick over the car sounds perfectly normal (minus a burble from the exhaust :p) That mean it cant be a injector?

The clutch bites perfectly, its done 48,000 miles with over 40,000 miles of 295lb/ft and it hasnt slipped once, so can the DMF get knackered whilst the clutch stays in on piece?

I have to admit, havnt checked oil levels, but will now, would over/under filling it cause this? I havnt checked the oil level for around 2 months (it has just been into a Seat garage so I really should have knowing how stupid they are)

Gearbox oil - was my first thought when the gears werent playing ball, but would that cause a loss of power?

Yup, standard downpipe is still on, I have done a few logs already, and from what EdB could see, everything seems fine, torque and power graph whent up fine, just the power didnt go up to 180bhp! It feel down on power when driving aswell.

Dont think settings have been changed on the gear selectors? Where would you change them? When you say it didnt like 4th/5th gear, in what way? Mine is dead... wont pull for life or money.

Thanks for any helpful hits or tips!
 

maxcars1

Full Member
Nov 9, 2004
735
0
in 4th and 5th gear it was like you had to change gear as it felt lik eit was missing. Have you looked at the maf logs? Sounds like you need to get it into JBS for a thorough check over
 

air121005

Active Member
Sep 28, 2006
1,609
6
Worcestershire
you say you have fitted a new exhaust, have you taken the CAT out and have a straight through pipe?

in a previous car ownership life i came across this information which may be the answer to your problem. :shrug:

most people want to take the CAT off as they sap so much power, the problem is taking the CAT out and substituting a straight pipe is not really correct. OK, this will certainly give you the power back the CAT takes away through restriction but this causes another problem. When exhaust gas comes out of the cylinder it produces sound/pressure waves that travel up and down the exhaust system, if these S/P waves can be controlled correctly they can be harnessed to draw extra gas from the cylinder and so make the engine more efficient. These S/P waves are controlled by the cam timing and the pulses go down the exhaust until they meet the first expansion chamber, silencer, CAT (anything that causes the size of the exhaust bore to rise significantly). As soon as the gas reaches this expanded section, the S/P wave stops and goes back to the cylinder head, as this wave hits the back of the valve it bounces back and causes a suction pulse that helps pull more gas out the next time the valve opens. The problem is the distance from the first expanded section to the cylinder head is critical, to get this pulse action working correctly, if this distance is not correct the wave goes back at the wrong time and hits the gas coming out of the valve and so stops the gas coming out rather than helping it. This is what happens when you take the CAT out, you no longer have an expanded section in the correct place and the S/P wave will go down the system until it reaches the first silencer box before returning. Before CAT's were fitted, this was the reason all cars had an expansion boxes in a similar position to where they now fit CAT's. I know some one will say, what about the VTR with the CAT on the down pipe, or the old mini with only one silencer at the rear. The complications of how these S/P waves travel is not quite as simple as above. Lets assume the correct distance from the valve head to the first silencer should be 80 inches, providing you double or treble the distance or half it, quarter it, the S/P waves will still work their effect, so having the CAT on the down pipe or just one silencer at the back can still be right, what is practically certain is that taking the CAT out and substituting a straight pipe will not be correct and so you will loose some power.

this info was taken from GMC Motorsports website http://www.gmcmotorsport.co.uk/, a very well respected Citroen & Pug Tuning company. the info is in the exhaust section about half way down ;)

IIRC, somebody with a derv noticed power loss when they used a de-cat pipe!

i'd like to be proved wrong though as i'm thinking of getting the de-cat section when i buy my non-res milltek:funk:
 
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T. Spark

Guest
Hmm, interesting read. But JBS Mike has a de-cat on his, and is running perfectly fine... its given me something else to worrie about tho, thanks :)

lol,

Max - Doesnt feel like its missing, just I have no power at all until 2.2k when the turbo spools up,
 

Sisson

Club member
Aug 18, 2005
1,662
0
Derbyshire
its not that poorly IMO.

you got 153bhp atw?

Mine managed 160 atw... with the same mods as you...

don't foget the temps at awesome were 28deg and there were a few people with low figs?
 

T. Spark

Guest
It is bloody poorly, the car judders, wont select gears remotely quickly.

As for power, it came out with 163bhp at the fly, which is about 20bhp down, and tbh it feels slower, and a standard MK3 Cupra could keep up with me... its poorly matey!
 

UncleFester

Grumpier by the day!
Apr 30, 2006
4,764
1
Milton Keynes
www.facebook.com
As i understood it, that CAT problem doesn't apply to turbo charged cars as there's a turbo in the way which creates its own backpressure ..... removing the CAT and replacing with a straight pipe shouldn't cause a problem at all, certainly had no problems on mine even when i had no CAT and no backbox.

Have you had your gearbox oil changed ( not sure if it shares this with the main sump) and have you checked that the gear selector isn't fouling on anything?
 

T. Spark

Guest
I havnt changed the gear box oil, but thinking I will do that... would that cause a loss of bhp but no torque?

How would I know the gear box isnt 'fouling' on anything matey?
 

UncleFester

Grumpier by the day!
Apr 30, 2006
4,764
1
Milton Keynes
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*as clueless as you are* just suggesting things i've picked up along the way on other cars ..... low oil or old oil in the gearbox might account for sluggish / stiff changes of gear though.

Of course it could be clutch related, i would guess the only way you'd know that for sure is to remove the box and have a look or get someone that is qualified to.

As for the loss of torque and bhp - no idea about that!

As with anything, trying the cheap basics first is probably a good idea .... after that you're in garage territory :(
 

T. Spark

Guest
Cheers matey :)

Thinks its going to get taken to Teddy J's about the gearbox and judder problem, and see if its down on power when standard

Will edit this thread in a few days once its booked in :p
 

UncleFester

Grumpier by the day!
Apr 30, 2006
4,764
1
Milton Keynes
www.facebook.com
If it's under warranty ... i'd do bugger all myself ..... in fact at risk of making stuff worse ( not sure that changing the gearbox oil or at least checking it will cause a problem) i'd definitely book it in for the judder and power loss.
 

Sisson

Club member
Aug 18, 2005
1,662
0
Derbyshire
As for power, it came out with 163bhp at the fly, which is about 20bhp down, and tbh it feels slower, and a standard MK3 Cupra could keep up with me... its poorly matey!

Fair enough dude. :)

Mine did make 173 fly figs.

So there is 10 bhp diff somewhere. [ exactly the same mods]

What fuel were you running on, when was the oil last changed?
 

T. Spark

Guest
Fair enough dude. :)

Mine did make 173 fly figs.

So there is 10 bhp diff somewhere. [ exactly the same mods]

What fuel were you running on, when was the oil last changed?

Just feels alot slower than it should be, the ibiza that whent on after me had 20bhp over mine with the same mods really, so...!?

Running Total (as local) but really gunna start going to a shell (sorta out of my way) and the oil has been changed twice in the last 5,000 miles!

If it's under warranty ... i'd do bugger all myself ..... in fact at risk of making stuff worse ( not sure that changing the gearbox oil or at least checking it will cause a problem) i'd definitely book it in for the judder and power loss.

Well, its 'sorta' under warrenty :)
 

T. Spark

Guest
Its just had a new MAF MAF MAF...

Well, they said it did anyway....
 

Tall-Paul

Previously ph2858 :D
Nov 12, 2006
671
0
Manchester and Preston
Why dont u get the MAF readings checked on vagcom? I did on mine and it was a little bit down so it was cleaned and all was well. Mabe you could try turning your map off then try a rr again and see if its ur engine or ecu?? Its really weird that you hadnt lost any torque though :confused:
 
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