Fg Turbo Surging

[XRsixtee]

My FG XR6 Turbo seems to surge or draw back when driving at the 50km speed limit, have noticed it at times at 60kms and 90kms per hour. Especially when cold. When holding the throttle staedy or on cruise just feel likes its pulling back all the time. The tacho also flutters slightly. Have had the computer reflashed at 3000kms service made a bit of difference but not a lot. Dealer reckons the 6spd auto might not know whether it should change or not - some how I think it should be better that that. Anyone else noticing this problem?

[FG270]

ive got the 6 speed manaul and ive got no dramas but my mate has a auto so ill see wat he says.

[PHANTMXR6]

My car surges also.

It only appears to happen in reverse at low speed and in the first couple of gears near idle speed.

Not really a big deal in my opinion. I just squeeze the throttle a little bit and it goes away.

Manual, by the way.

[Benny]

I too have noticed this with mine when it's cold and at idle speed in reverse. It's only very slight but it's there. I haven't had any issues while driving or under hard acceleration.

Benny

[avoturbo]

Mine surges when cold but isn't so bad if you change it up a gear so it's under more load. Once it's warmed up it's fine.

I figure it's the closed loop fuelling and haven't stressed about it too much but will suss it out once I get around to fitting my wideband.

[dule]

I think it's something with Electronic Throttle, one of the sensors probably gets a little confused sometimes. I had the same thing happen few times in a manual BAII when hot. Only happens on at cruise speed with very little throttle input. Doesn't really concern me as it's easily fixed by stabbing the problem.

These things are a little hard to diagnose as they don't happen all the time, I told the dealer once but they told me they couldn't notice anything, I knew they will not notice anything from the drive around the block but I just thought it might be a common problem they knew about.

Edited 27/09/08 09:40 AM by dule

[avoturbo]

In that situation it could be overrun fuel cut, sometimes that can cause this issue at very small throttle openings, also sitting on or around the injector on/off point for overrun can do it.

But my FG only does it when it's cold, so I'm betting on the closed loop fuelling coming in too early when the engine is cold.

[coombsie66]

Mine does exactly the same thing, but only at small throttle openings and when it is cold. Once its warmed up it's fine.

It does seem like a cold start mapping issue, glad to hear mines not the only one doing it! Still a little annoying when your creeping round the back streets whilst its cold. Not a problem I ever had with my old EB!!