1.6 fsi Possible misfire but no warning lamp.

S

Sama216

Member
Hi, I recently bought an '04 A2 1.6fsi Sport. It is in great condition but was misfiring slightly when I test drove it but no warning lamp was displaying. The dealer agreed to fix the misfire and thought it would need a new coil pack which was fitted. However, the car is still misfiring but it is more evident when it has had chance to warm up. There is much hesitation below 3000rpm with a surge at 3000rpm which then seems to tail off again. At a steady 75 mph there is a sensation of the engine surging slightly too.

Also, when I start the car the revs drop off significantly immediately after the engine starts and has dropped low enough to stall twice, engine was warm on both occasions. This still happens when the engine is cold but thus far has not caused a stall.

Third and finally, on my way to work the other morning approaching a roundabout as I braked gently, the ABS light, ASR light and a large red warning triangle all illuminated with some loud beeping. I turned the car off and back on, all lights still present. Got to work turned it off, came back 5mins later and all out.

Does anyone please have any advice on what could have caused or be causing the missfiring/ lack of power as It is still under warranty and I would like to get it running properly before it expires.

Are A2 1.6fsi's particularly unreliable? I couldn't find a great deal of bad press on them and hoped this would be a reliable car.
 
Hi and welcome to a2oc--i have an fsi a2 and in the three years i have had i have only had 2 coil packs go (45k miles driving). when i bought the car i purchased a cheep coil pack to keep in the boot(£6-ebay)after about 2 years i had one fail so i swapped it over-using elimination method to find the dodgy one.then a week later that one failed so replaced with a £12 ebay one and that has been on ever since.
As most owners fsi will confirm the fsi always has a slight almost misfire when changing from "stratified"injection to conventional injection--2800-3000 rpm.I hope you are running it on high octane petrol ie bp ultimate/tesco 99, as this really helps the engine run clean and more efficient.As the engine warms up it runs leaner so highlights the poor fuel quality.
So i recommend you fill up with quality fuel and run a tank of that through it and see if the hesitation/misfire is still there.if it is take it back to the garage and let them have another go.
hope this helps mike
 
Many thanks for the reply, I have filled it with Tesco 99. Will let the garage have a look as I think they have probably changed one pack and with the miss not being as evident when the car is cold assumed it was sorted. A friend at work has suggested that the fuel filter could be to blame for the stalling at idle so I may replace that too. I'm hoping it is something simple like a coil pack. Had a TVR previously and spent 6 months and lots of cash chasing a missfire to no avail so I am a bit twitchy when it comes to faults with no Warning light.:eek:
 
Just to add to what's been posted above, run on the highest octane fuel you can find, and go back to the garage to investigate further coil pack failures, it's common!
 
Thanks again for the advice, the hesitation at 2800rpm does normally come just before a surge in acceleration which would seem to back up the switch in fueling although the performance does seem to tail off thereafter, particularly in the higher gears. My main concern is the surge/ hesitation that can be felt at a steady 75 mph as this is definately past the point of the fuel switching to/from stratified mode. Have you used the Wynns Direct injection 3 product at all? I've seen it mentioned on here and wonder if it might improve things. Although the car has FSH I can't guarantee the previous owner ran it on super unleaded.
 
it may be worth getting the fuel filter changed as it is ofter over looked when servicing by the less professional places;)
not used Wynn's direct spray myself but i did read it is recommended in a service bulletin-including a product called sea foam.
hope you get it sorted mike
 
i also read somewhere on this site you should check and clean the earth points as this can cause problems.

look in the service repair section its one of the stickys

oli
 
Last edited:
Crank position sensor?

See my post in the service/repair forum about crank position sensor.

Does the cars idle constantly dip about 50rpm? The surging at 75mph is the same sysmptons I had.

Since I had the sensor replaced the car is transformed. The poor idle and surging had been happening for months and only in the last couple of weeks do a warning light appear (and clear itself a few days later).


Cheers

Alex
 
Hi, the garage had the car back in and have changed the clutch which has eliminated the juddering on setting off which was what I suspected anyway. I have put some Wynns injector cleaner through too. Whilst the stuttering does not seem as bad as it was it is definately still there but it seems to be a bit intermittant. It is at its worst whilst the engine is warming up. Not noticeable when cold and not as pronounced when hot. There is definately something amiss as I cannot possibly believe that this is a characteristic of the car. The garage also said that there were no fault codes recorded. How much is a new crank sensor as this may be my next port of call. Would a failing fuel pump bring up a fault code? As I work with hydraulics It can be acharacteristic of a failing pump to have surges in the hydraulic flow.
 
Hi all the above points are known things with an A2...i have just had a full service complete plus timing belt and water pump and car seems flat at the moment asked the garage what spark plugs they put in and they told me standard recommended NGK i had bosch super 4 in before so going back to them this week always ran on super juice so my problem looks like plugs..
 
nee777.a2 said:
Hi all the above points are known things with an A2...i have just had a full service complete plus timing belt and water pump and car seems flat at the moment asked the garage what spark plugs they put in and they told me standard recommended NGK i had bosch super 4 in before so going back to them this week always ran on super juice so my problem looks like plugs..
Click to expand...

It may be best to use genuine Audi plugs, only about £21 a set.

Alan
 
just took the NGK R out 20 miles and black sooted up,obviously over fueling...put old back in just to confirm
 
You must log in or register to reply here.
Back
Top