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Discussion Starter #1
So the short story is my van keeps going into limp mode when under load uphill etc.

I have changed the intercooler, done and egr delete, added a hard pipe kit, and Mr Muscled the turbo and replaced the N75....all to no avail... Limp mode still happening...

My van was mapped before removing the egr valve, would it need re-remaping?

Help appreciated as it's doing my head in.

Would really appreciate a 'to do list' for things to check / recheck and o replace....
 

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So the short story is my van keeps going into limp mode when under load uphill etc.

I have changed the intercooler, done and egr delete, added a hard pipe kit, and Mr Muscled the turbo and replaced the N75....all to no avail... Limp mode still happening...

My van was mapped before removing the egr valve, would it need re-remaping?

Help appreciated as it's doing my head in.

Would really appreciate a 'to do list' for things to check / recheck and o replace....
need to check ECU codes to see why it's actually going into limp mode, if it's an over boost code you may need to get the turbo off and get the VNT mechanism fully stripped out and serviced.
 

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Discussion Starter #3
Thanks Martin... will try that..., whats the chances of shearing a bolt when removing the turbo?

The van's a 53 plate T5,
 

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Thanks Martin... will try that..., whats the chances of shearing a bolt when removing the turbo?

The van's a 53 plate T5,
I don't know what engine you have but the early 2.5s have the manifold flange bolt to the turbo so if a bolt breaks it would be left in the turbo that you are removing.
 

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Discussion Starter #6
So from your kind advice I had someone look at the fault codes.

There were about 1 million to begin with, so cleared them and started over.

Immediately the MAF sensor was reading to high. From memory the reading should be around 240, mine was at 1270!

Disconnecting the MAF and driving made little difference, if anything, it was slightly better with it connected than without.

Now, having quickly looked up MAF sensor VW 1.9, I bumped into a thread where it was stated that the MAF sensor will read high if the ERG is removed. IS this correct?

Personally I don't see why the MAF sensor would read high given that it measures flow from the air inlet before hitting the turbo and anything else.

Before I fork out for a new sensor, are there any suggestions from you knowledgable chaps with anything else to try first?

Thanks in advance
 

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Discussion Starter #7
Check the map sensor and maf first
Map sesonr seems to be working. I.e., if i disconnect it, the van drives like a pile of kak. Re-connect it, back to normal...

As above, MAF sensor isn't reading correctly though, but am unsure if its a sensor fault or something else....
 

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Discussion Starter #9
Have you got a DPF.

I think you may need a working EGR valve to regenerate it
I don't believe so - my understanding was that the 1.9's do not have a DPF...

Though If someone could confirm this it may be helpful... - Though at the same time, if the van did have a DPF and it was 'blocked' would that not show up as a fault anyway?

Thanks
 

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Discussion Starter #10
Just a bump to the top....


So has anyone experienced high MAF sensor readings post egr delete?

Wondering if there is a simple fix before forking out £100 for a new sensor only to find the old one was fine...

Advice appreciated.

Thanks
 

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Just a bump to the top....


So has anyone experienced high MAF sensor readings post egr delete?

Wondering if there is a simple fix before forking out £100 for a new sensor only to find the old one was fine...

Advice appreciated.

Thanks
I did some data logs yesterday morning and I also have higher actual MAF than requested at idle and low throttle inputs.
I blanked my EGR last year when I did my cam change so that might explain the higher readings.
I will see if I have an old log done before the EGR blank to compare.
 

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Just a bump to the top....


So has anyone experienced high MAF sensor readings post egr delete?

Wondering if there is a simple fix before forking out £100 for a new sensor only to find the old one was fine...

Advice appreciated.

Thanks
I have just dug out some old data logs before I blanked my EGR and the airflow through the MAF is lower than now at idle/light throttle when the EGR is open.
I don't however get an issue now with an over airflow code on the ECU.
2004 2.5 130
 

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Re: ERG delete - Remap questions

Hello,
I have installed an EGR Blanking plate on one end of the EGR pipe on my van to stop the gasses recirculating back in to the engine. Car drove noticeably smoother straight away and seemed to remove some lag out of the turbo.
I now have (and knew I would having read the forums) the 'engine' light on the dash and the 'coil' light is flashing. All info I have read indicates it is directly related to the EGR blockage. And when I read the error codes from ECU it was confirmed as a recirculating thing.

-Do I need to have the ECU reprogrammed the EGR software on the ECU to fix this?
-Should I remove the EGR pipe altogether and blank off the other end also? (at the moment I've just put a blanking plate between the EGR pipe and the manifold.
-Or, can I just remove the EGR sensor to get rid of the 'engine' light and flashing 'coil' light….. even if that can be done.

Regards

Adrian
VW T5 Transporter 2.5 TDI
 

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Re: ERG delete - Remap questions

Hello,
I have installed an EGR Blanking plate on one end of the EGR pipe on my van to stop the gasses recirculating back in to the engine. Car drove noticeably smoother straight away and seemed to remove some lag out of the turbo.
I now have (and knew I would having read the forums) the 'engine' light on the dash and the 'coil' light is flashing. All info I have read indicates it is directly related to the EGR blockage. And when I read the error codes from ECU it was confirmed as a recirculating thing.

-Do I need to have the ECU reprogrammed the EGR software on the ECU to fix this?
-Should I remove the EGR pipe altogether and blank off the other end also? (at the moment I've just put a blanking plate between the EGR pipe and the manifold.
-Or, can I just remove the EGR sensor to get rid of the 'engine' light and flashing 'coil' light….. even if that can be done.

Regards

Adrian
VW T5 Transporter 2.5 TDI
It depends if you have the earlier axd/axe engine code (2003-2006) or the later bnz/bpc (2006-2009. The earlier doesn't need the map altered as it's a vacuum controlled egr where as the later is electronic and needs to be told not to be used.
With the egr blanked the engine will draw more air through the maf so the readings will be higher :)
 

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Also - does it have a DPF? IIRC the point at which they came in is somewhere during 2006 or early 2007 in Europe, but that may be completely different where you are...
 

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Thanks heaps. mine is 2008 so 'electronic' I'll get it re-mapped to delet EGR from ECU.

I have no idea if it has MAP.

Build was for Australian standards, but essentially the same car as that produced for UK market.
 

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MAF circuit high or, measured airflow above expected ??
Former is an electrical circuit / component fault.

Modelled airflow would be speed and manifold pressure comparison to MAF, changing the EGR rate would alter MAF observed slightly.
 
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