Runs rough no codes

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Dodg3r

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I have a 1999 agu , the car is running rough justnow but seams to be more so under load , at one point I was getting 5mpg while flames shooting out the exhaust , sometimes from idle in nuetral i can rev up to 2000ish revs and when I release the throttle it can drop right down to stalling point then idles perfect , I have changed the wiring loom , lambda, coil packs , spark plugs , maf , ignition amplifier , cam sensor , the injectors are all firing fine , car is timed right , no codes on vcds , when the car was moving it felt and sounded like a misfire , I'm at a complete loss with this car now it's always been looked after and now this all of a sudden , anybody got ideas?? , to top it off the missus car just shat it's turbo
 
By the sounds of it, it’s over fuelling, sorry to state the obvious... any chance of checking what the EGT sensor is showing?
 
S3AMJ said:
By the sounds of it, it’s over fuelling, sorry to state the obvious... any chance of checking what the EGT sensor is showing?
Click to expand...
your right its definatly over fuelling seams to be spitting it out the exhaust , can i check the EGT with VCDS lite and if so how do i do that , im new to vcds and not sure what im looking at with some of the measuring blocks
 
I believe it’s group 112.... if you check it when the engine is cold, keep an eye on it and see if it shoots up to 1100. That’s usually a sure sign it’s goosed.


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il go check justnow
S3AMJ said:
I believe it’s group 112.... if you check it when the engine is cold, keep an eye on it and see if it shoots up to 1100. That’s usually a sure sign it’s goosed.


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Click to expand...
il check it soon or the morning il let you know how i get on
 
okay ive learned the AGU engine doesnt read EGT or have a sensor for it
 
audi upgrades
Well there’s your problem right there haha! I’m kidding, yeah your right sorry. My mistake. Any vacuum leaks, that will also cause the car to run rough and over fuel


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Running issues like this are normally related to a faulty MAF or airleaks of some kind....

Unfortunately the AGU's ECU is not the brightest bulb in the pack and can make diagnosing issues tricky...

Easiest thing to check first is for air leaks... ideally using something like a smoke tester (some garages should offer this service) but most leaks can be easy to find as the AGU hasn't as many pipes as later cars..

Obvious signs are wet oil patches around pipes... oil should be inside the engine not outside...

<tuffty/>
 
S3AMJ said:
Well there’s your problem right there haha! I’m kidding, yeah your right sorry. My mistake. Any vacuum leaks, that will also cause the car to run rough and over fuel


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Click to expand...
I can't believe I overlooked that haha that cracked me up , Il check for leaks again
 
<tuffty/> said:
Running issues like this are normally related to a faulty MAF or airleaks of some kind....

Unfortunately the AGU's ECU is not the brightest bulb in the pack and can make diagnosing issues tricky...

Easiest thing to check first is for air leaks... ideally using something like a smoke tester (some garages should offer this service) but most leaks can be easy to find as the AGU hasn't as many pipes as later cars..

Obvious signs are wet oil patches around pipes... oil should be inside the engine not outside...

<tuffty/>
Click to expand...
I have four mafs here , I did have a maf code at the start of this problem but it went away after I changed the maf to a working one (maybe related?) As above Il check leaks and report here , just a thought here with all that fuel coming through could my 02 sensor be a fault now and possibly cause this problem ,it is new but has only been installed after this issue started (No fault code for it though)
 
Its plausible that you have killed the lambda but being narrowband its only something you can check on idle and part throttle conditions...

You could check fuel trims and see if they are excessive... this normally indicates issues around airleaks or over fuelling...

normally around +/- 5% but if higher/lower then suggests issues... high negative numbers suggests ecu is seeing too much fuel so is pulling out fuel via adaptions... high positive value suggests airleak so adding fuel to deal with it

<tuffty/>
 
<tuffty/> said:
Its plausible that you have killed the lambda but being narrowband its only something you can check on idle and part throttle conditions...

You could check fuel trims and see if they are excessive... this normally indicates issues around airleaks or over fuelling...

normally around +/- 5% but if higher/lower then suggests issues... high negative numbers suggests ecu is seeing too much fuel so is pulling out fuel via adaptions... high positive value suggests airleak so adding fuel to deal with it

<tuffty/>
Click to expand...
Okay I do have vcds lite can I check trims on there and what measuring blocks to use?
 
Ah ok... lite version only goes up to block 20 I think... trims are block 32

http://www.ross-tech.com/vag-com/m_blocks/

Block 001 has lambda adjustment so if thats jumping around a bit then might help diagnosing... assuming the M3.8 ECU supports this which I think it does...

AGU is not my area of expertise I'm afraid as not actually work on any myself personally...

<tuffty/>
 
I get upto block 025 in my version (newest from rosstech website) Block 001 doesn't have lambda but blocks 005 , 006 ,007 , 008 and 009 all have a box with lambda on it , strange because I only have one lambda on an AGU , blocks 005 and 006 are steady at around 14% but blocks 006 007 and 009 all behave erraticly between -4% - 6% and on block 008 the two lambda boxes stay at 0.0%
 
001 must be different for an AGU then... 005/006 % is load on ME7

Like I said before... not worked on AGU's so can't really help much on that... there are a few AGU guys on here that might be able to shed some light though

<tuffty/>
 
<tuffty/> said:
001 must be different for an AGU then... 005/006 % is load on ME7

Like I said before... not worked on AGU's so can't really help much on that... there are a few AGU guys on here that might be able to shed some light though

<tuffty/>
Click to expand...
thats fine all help appreciated thanks , im check for vacum leaks like you said as soon as the rain stops
 
Dodg3r said:
your right its definatly over fuelling seams to be spitting it out the exhaust , can i check the EGT with VCDS lite and if so how do i do that , im new to vcds and not sure what im looking at with some of the measuring blocks
Click to expand...
no egt on agu
 
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I think im getting the hang of it now , Is my measuring blocks on vcds different because there may not be a label file for my car , so as you said
Block (group) 1 Channel 3 is Lambda is the same for every car including mine it's just vcds has the wrong label file I have to make my own file with the correct names under the values shown?
 
Here is a picture of
20190523 200851
what I see on group 1 , car just started , the t.b. angle is 3.9 until I start the car then moves up to about 12 , is that the lambda reading , or if it is t.b angle shouldn't it be at 0 with only the ignition on , Also next picture is group 005 at idle and then group 005 at part throttle
20190523 201347
20190523 201318
 
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