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I solved this issue at last, with my CCWA. The problem stems from the smaller pipe that joins the EGR to the intake manifold. It gets completely gunked until it's barely a pinhole.

Take the intake manifold off, and scrape it good, then soak with the oven cleaner & scrub. It'll likely fix the issue, and give you a good chunk of power and economy back. Takes about 20 minutes to remove/replace, plus a couple hours washing.

If that doesn't cure it, it may be worth replacing the EGR, but mine was almost perfectly clean, and was only a few thousand miles old. Since cleaning the intake I haven't had the code, no even pending.
 
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I solved this issue at last, with my CCWA. The problem stems from the smaller pipe that joins the EGR to the intake manifold. It gets completely gunked until it's barely a pinhole.

Take the intake manifold off, and scrape it good, then soak with the oven cleaner & scrub. It'll likely fix the issue, and give you a good chunk of power and economy back. Takes about 20 minutes to remove/replace, plus a couple hours washing.

If that doesn't cure it, it may be worth replacing the EGR, but mine was almost perfectly clean, and was only a few thousand miles old. Since cleaning the intake I haven't had the code, no even pending.


Well that’s useful! Will point the garage straight at that pipe next week and see if it works for me as well. Any idea on how to keep it clean in the future?


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Well that’s useful! Will point the garage straight at that pipe next week and see if it works for me as well. Any idea on how to keep it clean in the future?


Sent from my iPhone using Tapatalk
Oil catch can, quality fuel. Not much else you can do otherwise, but that'll probably slow it down enough to never need to bother with it again.
 
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Wanted to update you guys.

Situation is now worse with another couple of faults coming up, namely:
5168 - Altitude Sensor / Boost Pressure Sensor | P1592 00 [175] - Implausible Correlation | 16.05.2019
4794 - Mass Air Flow Sensor (G70) | P0101 00 [101] - Implausible Signal | 15.05.2019

If I turn on the ignition and then start the engine - car goes into limp mode, i.e. flashing yellow glow plug light + constant emissions control system light.

If I start the engine without turning on the ingition first - no limp mode, but the emissions control system light is lit.

Car is going in for diagnostics on Wednesday, but if somebody has any ideas, please comment below. Getting sick and tired of this tbh.
 
Wanted to update you guys.

Situation is now worse with another couple of faults coming up, namely:
5168 - Altitude Sensor / Boost Pressure Sensor | P1592 00 [175] - Implausible Correlation | 16.05.2019
4794 - Mass Air Flow Sensor (G70) | P0101 00 [101] - Implausible Signal | 15.05.2019

If I turn on the ignition and then start the engine - car goes into limp mode, i.e. flashing yellow glow plug light + constant emissions control system light.

If I start the engine without turning on the ingition first - no limp mode, but the emissions control system light is lit.

Car is going in for diagnostics on Wednesday, but if somebody has any ideas, please comment below. Getting sick and tired of this tbh.
That sounds not too bad, just a bad sensor. Did you spray something down the intake by any chance?

Or, it could be a boost leak. Did you take the intake off and just not get it right putting it back?

Edit: bit of googling, sounds like a definite boost leak.
 
EGR valve broke when they tried to remove it for cleaning. I was told that this is a known risk, because the EGT valve is somewhat cooked from the heat of the exhaust gases overtime and becomes really fragile. Don't know if that is true or not but this is what I have been told.

There was some carbon build-up in the intake manifold, not too bad, but still restricting the flow.

New EGR ordered, will be in early next week. Will update you on the rest.
 
Image


Image


EGR valve atm


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Wtf that's a solid bit of metal? I've dropped one 6ft onto concrete and it didn't care!? How did they smash that
 
Well, it has been a full week now. So far:
1. the clogged EGR cooler was cleaned until it got a good flow,
2. the new EGR valve (OE Pierburg) was fitted,
3. MAF sensor was cleaned,
4. intake manifold was cleaned from minor carbon build-up.

Car is reassembled and now the mechanic is after the potential boost pressure leak. Will report his findings later on.

Hopefully the car will run fine now and my fuel "economy" will get back to normal.

Fingers crossed.
 
Last update: boost pressure sensor after the turbocharger was faulty and an OE Bosch one was fitted.

All error codes are gone, hope that lasts.

God, how I miss my car. Taking her for a 1,000 km round trip this weekend, will see how she acts :)
 
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