Rev meter fluctuations

[Mark1a3]

The needle on my rev meter fluctuates between 900rpms and 1100rpms when idle and the car seems to vibrate a little - any ideas what could be causing this? :confused: Mark.

[shark_90]

Hi Mark, welcome to VWAudiForum.

What engine is in your A3? It could be a bad MAF, bad spark plugs, or it could be that unmetred air is being drawn in somewhere.

[Mark1a3]

Thanks... like the site.

Its an Audi A3 1.8i 20v non turbo - 2000 model. I did try the plugs - put 4 new ngk's in yesterday. I have just bought an induction kit which i am ready to fit...

[Mark1a3]

Have read a lot about this problem and it appears like it could be a number of things. Looks like i may have had a slight coolant leak too so might take it too the audi garage. no idea of how much this will cost me but thanks for the initial advice anyhow!!

[henners38]

Did you ever get a fix for this? mine does the same, I have some other niggling little problems that may be related to the MAF sensor as well though.. be interesting to know..

[Mark1a3]

No fix as of yet - I'm going to the Audi garage to get a diagnostics this week as i've had some immobiliser issues too.

I have a feeling its going to be something simple like the timing but will probably cost me an arm and a leg from Audi!

Will keep you posted..

[woods109]

i had the same problem, took it to my local garage and they cleaned the throttle bodies. seems to sit abit better but is starting to do it again after a month or two will be happy to see what the problem is but thought id tell you what progress ive had :)

[Mark1a3]

My immobiliser issue was because of another key interfeering with with the signal of the immobiliser. Removed key - problem solved.

The lumpy idle can be a number of things and from all of the posts i've read it appears to be difficult to pin down the cause. Really trying to avoid taking it to audi after they quoted me £100 just to run diagnostic so will try and find a local with a VAG-COM kit first... just hope its not swine flu...