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Model specific boards => Golf mk4 => Topic started by: dan2252 on 11 August 2012, 22:59

Title: werid engine, power issue!
Post by: dan2252 on 11 August 2012, 22:59
right, my cars been doing this every so oftern and its geting rather anooying now. you'll be driving along under hard power and it will almost throw you through the windscreen like ive jammed brakes on! did it in second gear yesterday and it was that agressive it made the front wheels squeal! cant think for the life of me whats doing it,
 turbo waste gate had seazed up ive now sorted that re checked that and its still free
got 2 faults in engine for, somthing about intake manifold pressure exceeded or somthing, then a mixture too rich fault, but thats due to the blowing exhuast as its blowing just before lambda that wont be the cause as it was doing this before exhuast flexy went.
fitted a new genuine  n75 valve.
checked all vac lines and hoses wiring plugs im running out of ideas only thing i can think of is maybe a airflow meter would this cause this?
any advise guys on what to do?  thanks in advance danny!
Title: Re: werid engine, power issue!
Post by: dom on 11 August 2012, 23:43
It's called a rev limiter Danny, when the needle goes into the red it means change gear :wink:
Title: Re: werid engine, power issue!
Post by: jamie1989 on 11 August 2012, 23:50
LOL
Title: Re: werid engine, power issue!
Post by: dan2252 on 12 August 2012, 11:29
haha na it aint that dom ahah :) it happends mainly around 5k once its coming onto boost
Title: Re: werid engine, power issue!
Post by: Wazzzer on 12 August 2012, 13:00
limp mode, you're overboosting for some reason and the ECU is saving the engine
Title: Re: werid engine, power issue!
Post by: dan2252 on 12 August 2012, 13:21
after doing abit of searching found that the air flow meter controls boost on the agu is this true?
Title: Re: werid engine, power issue!
Post by: Wazzzer on 12 August 2012, 13:24
yes it does mate. You need to do some logs of the MAF readings, N75 duty etc to see what's going on. It could be over reading which is why it's shutting down
Title: Re: werid engine, power issue!
Post by: dom on 12 August 2012, 13:32
after doing abit of searching found that the air flow meter controls boost on the agu is this true?

Yeah it does, we can try my MAF on yours if you want? It's only a few weeks old & genuine one from your work :wink:
Title: Re: werid engine, power issue!
Post by: Wazzzer on 12 August 2012, 13:39
Dom not if yours is AUM and his is AGU...
Title: Re: werid engine, power issue!
Post by: dom on 12 August 2012, 13:53
Dom not if yours is AUM and his is AGU...

Yup, true that :grin: :rolleyes:
Title: Re: werid engine, power issue!
Post by: dan2252 on 12 August 2012, 17:24
what channels do i need to go into mate? if i can get some print outs of the readings and post them up on here will you know what they should roughly be?
Title: Re: werid engine, power issue!
Post by: Wazzzer on 12 August 2012, 21:13
I'll check what blocks you need. What sort of power should you be running?
Title: Re: werid engine, power issue!
Post by: dom on 12 August 2012, 21:43
I'll check what blocks you need. What sort of power should you be running?

I think he's got an AGU with KO3s, S3 Fuel Pump, FMIC, APR d/v, 2.5"(?) turbo back exhaust with decat, some kind of performance filter & a remap, so I'd guess 230ish?
Title: Re: werid engine, power issue!
Post by: Wazzzer on 12 August 2012, 21:55
say 225bhp as it makes it easier to compare my MAF readings  :laugh:

(http://img.photobucket.com/albums/0803/WesRS/logs002.jpg)

(http://img.photobucket.com/albums/0803/WesRS/logs003.jpg)

(http://img.photobucket.com/albums/0803/WesRS/logs025.jpg)

Try those blocks for starters :afro:
Title: Re: werid engine, power issue!
Post by: dan2252 on 12 August 2012, 23:27
sorry for the late reply guys been out, yeah its got front mount, remap, forge tip, apr recirc valve, ko3s, pipe cross pannel filter, s3 fuel fuel pump, 2.5 turbo back exhuast, will find out exact power in a few month when she goes on the rollers!  im gonna say power is going to be 200, 230 as its still on standard agu injectors at the moement.
 
il get some logs up asap what did you do then go for a drive taking it round the revs under full power? and just take snap shots of whats on the screen? :)
thanks for you help so far lads!
Title: Re: werid engine, power issue!
Post by: Wazzzer on 12 August 2012, 23:39
go to measuring blocks, select 002, 003 and 025 then start recording the logs, full throttle 3rd gear run from around 2k to redline

it will save the log file in the Program files -> VAG COM folder. Open this in excel and have a looksie :wink:
Title: Re: werid engine, power issue!
Post by: dan2252 on 12 August 2012, 23:46
il have to borrow vag com off lad at work. as i dont think our vw software will let us get in that far :) thanks for all the help though pal! :)
Title: Re: werid engine, power issue!
Post by: dan2252 on 14 August 2012, 18:44
right guys ive not managed to do vag com logs but used our computer at work to get rough readings just for now, the n75 load when you floor it in 3rd goes straight to 99 percent then fades off to 63 percent to the red line, and channel 002 i belive was giving me a reading of 176.4 g/s at 5600rpm thats all i could do for now lad at work forgot to bring his vag com :( so is that about right? sorry the readings are so vauge it was hard trying to balance computer and freeze frame the screen haha
Title: Re: werid engine, power issue!
Post by: dan2252 on 14 August 2012, 21:26
also is it true you can work out the rough bhp from your air flow meter readings? is the a guide how too? :)