Erratic idle

[s5joe]

I am haven a little issue with my s3 it's got erratic idle and loss of power sometimes I have had it plugged in and it's come up with maf signal too high I don't just want to go and get a new one but when it gets reset its ok for about five min than it starts doing it again and the traction control light comes on and stays on its strange as it only starts doing it when the light comes on.

 

[Sevv]

i joe i think i know what your talking about however you'd need to get it scaned with the VCDS see if any has one in your vicinty.. eratic idle could be ur MAF, check ur boost pipes concerning loose of power as i had that, and concerning your esp light which i have that issue too however i had (or should i say have to ) change my lateral and acceleration sensor inside the car... but all this is guess work as you'd need a scan if you havent scanned already.. i have a few threads concerning your problems too id check them.. tuffy has been great help to me so far

 

[s5joe]

I have had is scanned and it's saying maf signal too high.

 

[sportstractor]

Well that's a good indication that the MAF is ********, try unplugging the MAF sensor, it will being the the CEL light, but if you MAF is ********, it will run better.

Chance are the maf is ******** because they don't last very long, you can trade your old one in for a new one. Just make sure you get a genuine part and eBay ones are ****e

 

[s5joe]

I have got one off a gti turbo I had I was just goin to change the sensors over to see it that made any difference I am putting my money in the maf so far tho as its getting worse

 

[s5joe]

But it will go into limp mode if I unplug it won't it

 

[<tuffty/>]

Sensors are different between a GTI turbo and an S3 so it may cause other issues... erratic idle is normally a vac leak... check block 032 and see what the fuel trims are doing (when the engine has run for a little while)... do not reset any fault codes until you have checked this block though as it will reset fuel trims too...

I highish figure in the short term trim would suggest a vac leak..

<tuffty/>

 

[camscockle20vT]

But it will go into limp mode if I unplug it won't it

Nope.

 

[s5joe]

Quick update i have changed the maf and its still the same i have been chatting to someone and it could be the temp sender or the acelarator sensor but what else he siad was a vac leak but the traction control light keeps on staying on and i can feel it pull back when it comes on.

 

[s3dave]

Quick update i have changed the maf and its still the same i have been chatting to someone and it could be the temp sender or the acelarator sensor but what else he siad was a vac leak but the traction control light keeps on staying on and i can feel it pull back when it comes on.

It sounds like the MAF is ******** it can throw the traction light on too......

 

[s5joe]

Well I have got it booked in at a dyno centre to see what it's doin but I have tryed a different maf and it made no difference

 

[Pops848]

I had a similar fault yesterday on my A3 1.8t. Traction light came on and the throttle was not responding. Just sped up and slowed down by itself. It blew the cts out ad dumped all its coolant. Going to replace thermostat and see what difference it makes

 

[s5joe]

Well I have just been and got a new maf and temp sender and it's no different at all.

 

[S3lvo]

Hi Joe,

I changed my air filter yesterday, and unplugged my maf when I did it. The red plastic seperators in the plug were so brittle the breeze literally broke them... no lie!! When I put it back together it was idling very rough and put the traction control light on and the EML... drove it back down to london from hull and it was fine when warm and the traction light went off, but still slightly erratic on idle. I've just had temp sender changed which was fine and ignition coils done which didn't make any difference to my performance, only difference has been since the maf was unplugged yest. Have you checked the connectors on the plug going into the maf? Also, if anyone knows the best place to get one of those I'd be grateful!

Sorry.. bit long winded there!

Matt

 

[s5joe]

It has been booked into a place later to see what is goin on there maf readings engine temps the lot even in the dyno and a smoke test so I'll know later what is up with it.

 

[s5joe]

It's all sorted out now no leaks it just wanted all the settings doin properly