Oskar
A2OC Donor
For the last year (my entire ownership) for my 1.4 AUA, I have had issues with low down torque, cold starting, lean mix smell, poor MPG (I hope), general lack of horsepower and a lack of willingness to rev over about 3500rpm.
So I did many of the recommended fixes.
Refurb the main engine earth (both ends)
New EGR valve (which as stuck)
Clean the S pipe between EGR and throttle body
New Coilpack (single)
Extra earth from head to body
New fuel filter.
new 'proper' spark plugs
and of course, only the right 99 octane petrol.
There was just no oommpphhh. It really felt 'held back' which I took as not enough fuel or air getting into the engine. I doubted it was compression, as there was an even idle, and no roughness in any running, which indicated at least a consistent compression on each cylinder.
The 2 posts below gave me the idea to change my pre-cat lambda, even though I have never had any VCDS engine codes (for anything).
https://www.a2oc.net/community/index.php?threads/refurbishing-an-aua.38503/
https://www.a2oc.net/community/index.php?threads/pre-cat-lambda-replacement-1-4-petrol.37282/
Well, new one arrived today, and even just driving around the block, I can see a real difference. I do hope all the other aspects are resolved, which will take some longer drives to determine, but even if it remains as is, it is much better.
My car has only done 80,000m, but perhaps they were not good miles..... The part I took off was made in Japan, but I cannot see any branding, so don't know if it was original or a replacement.
I purchased part number 036906262J, where the offical part number is 036906265J. The only difference appears to be the length of the cable (mine is far too long, but some cable ties sorted that).
No VCDS codes or engine lights etc. I'm sure they are exactly the same, and the part I bought was a sealed genuine VAG part, so should be good! (£50, vs the NGK part of over £100!).
Anyway, if you have an AUA or BBY, and it is a bit sluggish and annoying in regards to mixture, a new pre-cat lambda may just sort it for you.
I now look forward to over 40mpg for mixed routes. I think I also now need to get on with the front brake refurb, as it is way more zippy!
So I did many of the recommended fixes.
Refurb the main engine earth (both ends)
New EGR valve (which as stuck)
Clean the S pipe between EGR and throttle body
New Coilpack (single)
Extra earth from head to body
New fuel filter.
new 'proper' spark plugs
and of course, only the right 99 octane petrol.
There was just no oommpphhh. It really felt 'held back' which I took as not enough fuel or air getting into the engine. I doubted it was compression, as there was an even idle, and no roughness in any running, which indicated at least a consistent compression on each cylinder.
The 2 posts below gave me the idea to change my pre-cat lambda, even though I have never had any VCDS engine codes (for anything).
https://www.a2oc.net/community/index.php?threads/refurbishing-an-aua.38503/
https://www.a2oc.net/community/index.php?threads/pre-cat-lambda-replacement-1-4-petrol.37282/
Well, new one arrived today, and even just driving around the block, I can see a real difference. I do hope all the other aspects are resolved, which will take some longer drives to determine, but even if it remains as is, it is much better.
My car has only done 80,000m, but perhaps they were not good miles..... The part I took off was made in Japan, but I cannot see any branding, so don't know if it was original or a replacement.
I purchased part number 036906262J, where the offical part number is 036906265J. The only difference appears to be the length of the cable (mine is far too long, but some cable ties sorted that).
No VCDS codes or engine lights etc. I'm sure they are exactly the same, and the part I bought was a sealed genuine VAG part, so should be good! (£50, vs the NGK part of over £100!).
Anyway, if you have an AUA or BBY, and it is a bit sluggish and annoying in regards to mixture, a new pre-cat lambda may just sort it for you.
I now look forward to over 40mpg for mixed routes. I think I also now need to get on with the front brake refurb, as it is way more zippy!
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