Help Again please. Audi A4 1.8t 190 Bex Engine Loss of Power

dlhudson39

Registered User
Joined
Mar 7, 2013
Messages
8
Reaction score
0
Points
1
Location
NULL
Hi Again All. Throwing out the challenge again.

Lets start with the simple stuff.
I have a UK Audi A4(190 6speed Manual) 1.8t B6 year 2004 BEX engine.
I had the engine light come on with the code for lean bank 1. The only codethat has come up on my laptop reader.
I consider my self good at fault finding,but this is starting to wind me up.

Part 1:

So i went through the following to iron out that fault.
1. Oil (Audi equiv) & Filter change.
2: New Bosch super4 spark plugs x4.
3: New set of Coil Packs x 4.
4: Replaced the PCV Valvle & attached 3 way hose for good messure.
5: Ran tank dry and filled up and used Redex fuel systemcleaner.
6: Cleaned Air mass housing and grill. Replaced Air flow Mass meter. (OEM Equiv)

Cleared the code yet still runs miss firing and top endspeed very poor.
Using alot of fuel due to running rough too.

So i replace the spark plugswith Bosch again.
Checked they all were firing, which they were.
All coils firing and in firmly.
Put old air flow meterback in & it ran very rough, so knew the new one
was ok. So put back in. Reset all codes & went off again.

It still is very rough yet no engine light yet.
Part2:


Right i thought i solved it.
I found & replaced the faulty split Vac 3way hose and the broken vbreather alve inside.
Then replaced the down Vac pipe to the engine block. Which was amazingly trickyto remove.
As like everyone says, it breaks off in pieces. Replaced with clip & rubber seal ring.

2.5hrs later all nice new pipes fixed in & re-clipped in.
Reset engine management code.
Engine hissing is considerable less. I thought....yes.........I get all that smooth turbopower back that
i had before!!!!

But now driving is still terrible, the loss of power is quite significant.
Top end speed is massivly less & struggles to accelerate on the hills.

Before all this & the engine light coming on, the cars performance wasawesome.
But after finding the split vac hose, replacing 2x faulty breather valve,replacing all coil packs, 2 lots of bosch super4 spark
plugs tried, oil & filter change. Im pulling my hair out.
It isnt jumping or jerking as it did, just real loss of power or even turbo boost.

Questions & support please all.
1: Could it be faulty coil pack leads, yet no engine management light yet. But sparks are clearly working.
2: How can i check if its the turbo, would that come up on engine fault light.
3: What are my other options to check & iron out please.
4: The Cambelt was done a while back but with the new coils, sparks & hoses could it be timing??
Help please gang
Thanks
Danny
 
Hi
Im running a bluetooth OBDII & EasyOBDII free software that throws up codes and clears & gives live data.
Codes mainly Lean Bank & once oxygen sensor but that was because it was running so rough.
Also listening to it, a low burbling sound seems to be coming from base of my Standard Airfilter.
It does have a high flow K&N replacement filter in but it is an unusal noise.
Thanks Again
Helppppppp
 
You need to get VCDS/Vagcom on it as there are a lot of VAG codes that generic readers don't recognise.
The other thing worth noting is that the MAF & coolant temp sensors often fail without throwing a code & the only way to be sure they are working correctly is to look at the measuring blocks or log them in VCDS/Vagcom. There are several engine sensors which will only cause the ECU to throw a code if they have shorted to ground or become intermittent, so if the ECU is still gettting a signal even if it's wrong it doesn't flag up a problem.
Golden rule with all VAG engine sensors is to use genuine VAG parts only. You shouldn't rule out the MAF sensor as you say you used an OEM equivalent.
 
as above get it on vcds and do some logs
 
what coil packs sis you use ?
have you tried swaping packs see if the miss follows the packs ?
turbo wont show up any codes but wont usaly make the car miss
 
Thanks for the advice again guys.
1: Will try putting the the old MAF back in, but have done this once & engine ran very rough. Will let you know.
2: Any advice on VCDS software for my laptop? wher to i go to get it? Will it still work with my Bluetooth sender?
3: Driving around now for a few days hoping it will even out but no. Its a defo massive lack of power in aceleration.
Especially around hills. No instant overtaking umph!
Good example would be. In 6th gear on the motorway you could pull away smoothly to 90 very quickly.
But now after solving the cracked pipe it just isnt there, very slow power delivery. Its not so much missfire back like
its missing loads of power.
FYI also. I tried some new coil packs 2 months ago, some were cheap and odd brands. All new from eurocarparts just
the ones they had. Thought it could of been those so took them back & upgraded to all new matching Beru germsn ones.
Keep the help coming please as i cant afford to loose my car, really love it as i know whats its capable of.
Also To note guys, when the vac leak was present. Pulling the dipstick out made hissing loud sound and engine dipped in tick over, same for when i undid oil cover. Now vac leak sealed, when i do the same no noise and car carries on ticking over nicely?

My thoughts could be
- Faulty wategate or Turbo?
- Could my Cat be clogged?
- Loss of pressure somewhere else?

I really do apreiciate all your thoughts & advice.
Thankyou
Danny
 
I would defo say there is a boost leak in your pipes, check/replace them all, the tiniest pin hole will lose loads of power.
mine went just above the catalytic converter if that's any use to you!
 
You really do have to have OCD tendances to deal with this. My old Audi 80 Coupe never had these issues.
Just big parts went, plug in another lol.

right update so far:-
1: Put old MAF back in & still exactly same issue. Lack of power!!
2: Engine light fault that comes up is Oxygen sensor circuit malfunction. Which prob would throw up
fault if Vac leak somewhere.
3: Stopped and had another listen....oh joy another hiss from a top vac pump. So little trip to
VW TPS in Canterbury whe are great. To get this part & replace surrounding vac hose and chk valves.

Think smoke test after this next lot of replacement parts.
Is this something i can do my self & what do i need chaps.

Cheers all & please keep the ideas & shared faulst coming.
Danny
 
Did you solve this? Sorry for thread revival!

Sent from my XT1572 using Tapatalk