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bakerboy-2007
08-04-2011, 08:06 PM
Hi guys just after some info...
My vr been playin a silly game over about 4 weeks, I will do my best to explain what has been happening...

Started on a long journey when at constant speed exhaust tone dips and car feels to loose momentum but rpm doesn't drop just a slight power loss an slight juddering if I hold the speed, I put accelerator peddle down car picks up and no issue untill sitting at steady speed it does it again,

Also if I boot it hard car goes like a train upto around 120mph then it's like hitting a wall the car jolts and power loss!!! If I accelerate steady she will hit 145 without missing a beat and hold it !!!

Iv pulled the codes nothIng flashing !!

My mechanic friend questioned fuel delivery so I changed the petrol pump and FPR for used items I sourced but car still playing up ,

I have been looking at threads on fuel cut and this could be the issue, questiOn being could my MAF be on the blink ????

As I understand it measures the amount of airflow and reports to ECU which then inputs enough fuel , It does sem to be runnning rich as working out 17-19mpg taking it easy !!!!

As always all advice much appreciated

Davezj
08-04-2011, 09:01 PM
has you car been delimited for speed as 120 shows on the dash when you hit the 112mph speed limiter.
when i hit the speed limiter in first VR4 it was like hitting a brick wall all power gone for what seemed like 2-3 seconds then it come back. but i never tried to go any quicker than the displayed 120mph (on a private test track of course).
so i don't know if will let you increase your speed past the limiter if you accelerate more slowly.
have you turned the boost up, past the factory past the 0.6 bar standard. i have never hit fuel cut at staock boost.
the only time i have heard of people suffering with fuel cut is after the boost is turned up. if you have turned it up, turn it back down until you don't hit it.

ianturbo
08-04-2011, 09:39 PM
Hi guys just after some info...
My vr been playin a silly game over about 4 weeks, I will do my best to explain what has been happening...

Started on a long journey when at constant speed exhaust tone dips and car feels to loose momentum but rpm doesn't drop just a slight power loss an slight juddering if I hold the speed, I put accelerator peddle down car picks up and no issue untill sitting at steady speed it does it again,

Also if I boot it hard car goes like a train upto around 120mph then it's like hitting a wall the car jolts and power loss!!! If I accelerate steady she will hit 145 without missing a beat and hold it !!!

Iv pulled the codes nothIng flashing !!

My mechanic friend questioned fuel delivery so I changed the petrol pump and FPR for used items I sourced but car still playing up ,

I have been looking at threads on fuel cut and this could be the issue, questiOn being could my MAF be on the blink ????

As I understand it measures the amount of airflow and reports to ECU which then inputs enough fuel , It does sem to be runnning rich as working out 17-19mpg taking it easy !!!!

As always all advice much appreciated

if you can cure this let me know mines been like that for 4 years !!if it don't do the cutout thing then go again ill miss it !!
ian

bakerboy-2007
08-04-2011, 09:54 PM
Thanks guys

Car is runnIng stock boost now

Nick Mann will be along in a mO to correct me if I get this wrong but engne was replaced with nuttrjohns old one an was running 350bhp once, car was fitted with map 2 and updated FPR and fuel pump and ebc but this all removed and returned to stock before I bought the car

Iv looked for boost leaks but nothing

I might fit an mbc and guage over the weekend and see if I can cure it with messing with boost limit???

Could it be clutch slip ?? It's an auto!! Oil ruby red !!!

ianturbo
08-04-2011, 10:13 PM
i put a MBC on mine and it does the same ,the engine missfires then after a few seconds picks up again , i went on rollin road day hopin to get some answers but no it ran like a dream !!
ian

Nick Mann
08-04-2011, 10:17 PM
The cars history is pretty much as you have said. I wonder if an evo scan log would show anything up?

bradc
08-04-2011, 10:39 PM
evoscan would make sense to see what happens to the maf values when the problem occurs.

bakerboy-2007
08-04-2011, 10:40 PM
Anyone local with an evoscan?? Or is it cheaper to buy the cable n software ??

Thanks for your time chaps

Davezj
08-04-2011, 10:50 PM
if you just want to log data the $25 for the software and £15 for a VAG COM cable from ebay is the cheapest way to do it.

unless evoscan software has increased in price but it cost me $25 with lifetime upgades.

bakerboy-2007
08-04-2011, 11:15 PM
Cheers rave I have just found the thread

Ian have you tried swapping you MAF ???

ianturbo
09-04-2011, 01:58 AM
yep swapped MaF but still , its hard to say but engine seems to shut off for a second and then goes again , am used to it now though ,

ian

bakerboy-2007
09-04-2011, 09:36 AM
Yeh that's how it is pal ...

You say yours has bin doin it for 4 years ! No adverse affects on the engine???

ianturbo
09-04-2011, 08:46 PM
Yeh that's how it is pal ...

You say yours has bin doin it for 4 years ! No adverse affects on the engine???

its not blown up !! (yet )/Hmmm
ian