Audi a3 1.8t recovery and many problems.

nixdorf

nixdorf

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Hello guys!

I have bought Audi a3 1.8T AGU engine code. The car had broke the timing belt and when I took it was into parts (process of recovery, but the owner had not time and money to continue). After I bought the car friend of mine helped me replace the broken stuff and assemble everything together.
Now I have following problems:
1.Temperature gauge on the instrument cluster shows a bit after the middle seems like 95 degrees (not sure is it a big problem but according to VCDS temperature is fine ) have tried to change the temperature sensor same problem.
2. The engine does not feel well. After engine is started staying in idle feels like it misfire (while attached to VCDS the showed rpms were 880 and when it was that misfire it showed 840 then back up to 880 like this all the time)
3. While driving most of the time I feel "lag" while accelerating (not sure is it caused by the 2nd problem). But I have replaced the spark plugs, ignition module, Forge Diverter Splitter Valve, also changed some of the vacuums hoses(picture below). Maybe good input will be VCDS readings but I do not have any idea which exactly will be useful. Engine is not throwing any error codes except for the ABS and the CLIMA.


I do not own a boost gauge at the moment (have ordered one still waiting for it to arrive )
I am studying in Denmark and it is crazy expensive to bring the car to mechanic, so I hope you can help me out with that.
 
Sorry I can't help with much else but the temperature seems fine especially if vcds says so, the needle is always I little bit out from what I hear... if vcds says your good then you probably are... again sorry I can't help with much else but it's one worry off your mind I suppose

Ben
 
I'd start with ALL the pcv pipes, it's easy to over diagnose and it ends up being a split hose. I recently had an issue with my AGU and looking at where Id capped off had a tiny split that only interested once warmed up. Temp sat at 90 is perfect. If it sits above that or below for too long then there are issues. Too low is often one of the thermostats (there's two).

Sent from my XT1572 using Tapatalk
 
Just one thermostat, may not be opening fully, making the temp a little high, misfire could be the coil packs, or even the wiring breaking down, the split R valve is a bad idea on this engine, replace with standard Bosch item.
 
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Not 100% sure you've still got one fitted, but a Forge Split-R is a downgrade for these engines, especially an AGU, which doesn't have the clever wideband ECU to fall back on.

Fit an OEM diverter valve, they're very afforable, and don't need upgrading... Unless you're going for real high figures maybe.

Also, @<tuffty/> has been known to ban people for fitting a Split-R...
 
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Hello everybody,
At first I would like to say thanks for the responses, I have been off for a while and did not had the chance to write back in here.
So here is small update:
1. I needed to swap the turbo because mine turn out to be broken (The company manufacturer of the turbo claims to be K03s for engine code AUM). Anyway I mounted the turbo and though everything will be all right and I stuck on the last step, fitting the air intake pipe. The new turbo intake was with approx 1mm wide so I said fine I will buy a TIP and fit it in.
2. I order the TIP and I tried to fit it, it wasn't easy because of the little amount space and I still don't like how everything got crowded.
3. Time to start the car finally the result was = HORRIBLE , the car was barely accelerating, it seems like there is no boost... I have checked vacuums etc.. without any luck.
4. I have tested the MAF sensor, have run test through VCDS for boost pressure control valve (n75) also seems to work, as you all said to replace the DV with 007p did that as well..

So I have no Idea what to do next!
Maybe I need remap, check all the intercooler pipes, some other sensor causing this ?

For the previous temperature problem it turned out that to be leak from the turbo cooling pipes.

EDIT: Also what have made me an impression (not sure is it safety but I thought is good to mention) When engine started and accelerating car on place can't go further than 5800-5900rpm.
Today one of the times car didn't wanted to start so I attached the VCDS and it throw an error for the Crankshaft sensor, after deleted car started and everything seemed normal. It did this one more time and that was no problem at the moment. Is it possible intermittent error from the crankshaft sensor to have something to do with all ?
 
Last edited:
Just had to replace my crank sensor, was the same as yours, stops you over revving, bit like a soft limp mode, change for a new one before it packs up completely, runs a lot better now and my idle feels a lot smoother.
 
andy68 said:
Just had to replace my crank sensor, was the same as yours, stops you over revving, bit like a soft limp mode, change for a new one before it packs up completely, runs a lot better now and my idle feels a lot smoother.
Click to expand...

Now that you mention it, this happened to me too! Never connected the dots... Car would sometimes hit a wall under 6k rpm while accelerating... It wouldn't start with a warm engine (this was correctly diagnosed as being crankshaft position sensor/engine speed sensor).

Never realised I haven't had the former since fixing the latter :)
 
It has been a while since my last post.. :(
The Update is:
1. I have replaced Crank Sensor
2. Needed to replace fuel pump
The car runs better for sure but there is no boost and that is what it is... no codes no nothing, I have no ideas anymore what to do.
But I have one question.

13241474 1230754100282029 615002959 o


Does the marked with red Pipe should expand when rev the engine? Because what it happens now is when rev it does not expand, only when I release back to idle expands a bit for a second...
 
nixdorf said:
Does the marked with red Pipe should expand when rev the engine? Because what it happens now is when rev it does not expand, only when I release back to idle expands a bit for a second...
Click to expand...

If it expands when you release back to idle, that means it's being pressurized from the turbo because the throttle body closes. This would indicate the DV isn't working correctly... Looking at your DV, it appears to be fitted the wrong way around.
 
Erikn89nl said:
If it expands when you release back to idle, that means it's being pressurized from the turbo because the throttle body closes. This would indicate the DV isn't working correctly... Looking at your DV, it appears to be fitted the wrong way around.
Click to expand...
It looks like a split-r so fitted the right way but... it shouldn't be fitted at all if it is a split-r as we all know they are utter rubbish!...

This won't necessarily cause lack of boost unless its stuck open but I would fit an OE DV and bin off the split-r regardless..

By lack of boost do you mean no boost at all? as an expanding pipe suggests some pressure is there... what is the actual boost you are seeing and what are you expecting?

What boost is it actually producing? I assume you have a gauge to see this? I also assume that the gauge is working?

<tuffty/>
 
audi upgrades
andy68 said:
Just had to replace my crank sensor, was the same as yours, stops you over revving, bit like a soft limp mode, change for a new one before it packs up completely, runs a lot better now and my idle feels a lot smoother.
Click to expand...

I may need to replace mine this weekend. Any tips? Drop oil and remove filter for more room or not necessary?

Thanks.
 
possible with oil filter in place, removal does make it easier.
 
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