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Discussion Starter · #1 ·
My car occasionally (once every couple of days, or once every few weeks) seems to have a bit of a breathing problem at around 1800 to 2000 rpm on light throttle application it might 2 or 3 times in 2 or 3 seconds 'miss' and burp out the back a load of unburnt diesel I guess....then it might not do it again for a day or 3 weeks.

I only do about ~8500 miles a year and not any daily thrashing.....does it just need a good 'boot' or will someone with VAG-COM be able to enlighten me.

There are no lights coming on the dashboard & it revs cleanly to 4000rpm when I booted after this event last night.
 

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Discussion Starter · #2 ·
TTT

Any suggestions appreciated.(For info. it has 33,000 miles and is a 51 plate model 115 PD)
 

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you need to redline it in third gear but i used to do it in 1st 2nd and 3rd. That should clear all the crap out. My local garage reckoned this should be done once a week to keep it clear. You could also put some red-x or simular in the fuel incase you have a blockage anywhere.

I was just clearing the engine out officer, Honest !
 

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Discussion Starter · #8 ·
you need to redline it in third gear but i used to do it in 1st 2nd and 3rd. That should clear all the crap out. My local garage reckoned this should be done once a week to keep it clear. You could also put some red-x or simular in the fuel incase you have a blockage anywhere. I was just clearing the engine out officer, Honest !
will do...

'macdaddy told me to do it officer'
 

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Discussion Starter · #11 ·
Update :

Its back again, intermittent, it had cleared when using Tesco Diesel & after a 40,000 mile service at a independant.(Also before the service I'd done about 800 mile in 3 days.

Use Red-ex & Millers each fill up, but back on Shell, but notice it only consistently manifests itself on partial throttle through 1800rpm and when the tank has emptied to about half full....

Push the throttle to the floor from 1000rpm, picks up lazily until the turbo kicks (~1500rpm) in and runs past 1800rpm every time without fail????????????
 

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Paul,

Sorry to hear you are having problems - presume you have had the diagnostics run to see if there are any fault codes and also checked/greased the connector to the MAF! Mine is now on 65k and has just been MOTd again without any problems (for which I was very thankful as I can not afford any mega bills at the moment) but I,m thinking about putting the old Mk2 back on the road for the winter at the end of the month. Hope you manage to get your problem sorted without too much expense.
 

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mine does this too. i thought it was a common fault on them...??? i'm sure i read somewhere on this site that its a known fault and some people have had a replacement ecu with different firmware.
 

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Paul,

Sounds exactly like the hesitation Amar had on his car a year ago! He ran the EGR adaption with VAG Com to turn it all the way down and also cleaned out the EGR pipe. Might be worth speaking to him or R44MS_K ad find out exactly what he did. Post what you find here since it's clear others have the same issue.

By the way, look for a bubble between the fuel filter and the injector rail?
 

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Discussion Starter · #16 ·
Bubble or air lock has been mentioned before, the problem did go away for 2-3 months after the service which included a new fuel filter, how do I check for a bubble?

Cleaning EGR pipe, is that a half hour job or longer?
 

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on my car, the pipes from the filter to the rail are clear so quite easy to see, otherwise you'll just have to bleed it through?!?!

Cleaning up the EGR is probably a 2 hour job. Took me a bit longer as I ran into issues last time through inexpereince. There are 3 hex bolts attaching it to the inlet manifold, one of which is behind the EGR pipe attached by two hex bolts under the valve. Be sure to save the metal gasket on the EGR pipe.

I'd remove the bolts at the other end of the EGR pipe and completely remove the EGR pipe. Might need to remove the flex house between the MAF and inlet manifold to make the other end easy to get to. Metal gasket at this end too.

I used some brake cleaner initially but found it wasn't working as well as I'd like so used carb cleaner instead - worked a treat. The mitakee I made was re-attaching the EGR valve to the inlet manifold and then the EGR pipe to the valve - managed to cross thread the valve and had to use a thread tap to sort it. Easier to attach the pipe loosely to the valve out of the car so you can still get to the third hex bolt to attach the valve to the manifold.

Hope that makes sense!
 

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Discussion Starter · #18 ·
on my car, the pipes from the filter to the rail are clear so quite easy to see, otherwise you'll just have to bleed it through?!?!

Cleaning up the EGR is probably a 2 hour job. Took me a bit longer as I ran into issues last time through inexpereince. There are 3 hex bolts attaching it to the inlet manifold, one of which is behind the EGR pipe attached by two hex bolts under the valve. Be sure to save the metal gasket on the EGR pipe.

I'd remove the bolts at the other end of the EGR pipe and completely remove the EGR pipe. Might need to remove the flex house between the MAF and inlet manifold to make the other end easy to get to. Metal gasket at this end too.

I used some brake cleaner initially but found it wasn't working as well as I'd like so used carb cleaner instead - worked a treat. The mitakee I made was re-attaching the EGR valve to the inlet manifold and then the EGR pipe to the valve - managed to cross thread the valve and had to use a thread tap to sort it. Easier to attach the pipe loosely to the valve out of the car so you can still get to the third hex bolt to attach the valve to the manifold.

Hope that makes sense!
Sounds like a job for my independant, & I'll go to work for 3 hours on a Sunday to pay for it
 
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