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Technical => Diagnostics => Topic started by: viki300 on November 27, 2013, 01:14:34 AM



Title: Audi S3 MY 2000 1.8t APY hesitation and misfire one cyl no DTC
Post by: viki300 on November 27, 2013, 01:14:34 AM
Hi i got this problem on this car so one cylinder No 3 allways spark plug wet and kind of dead rpm range 3000-5000 and then it goes again idle normal and if press throttle pedal fast it hesitate and kind of misfire and one cylinder burns very badly so far coil replaced and spark plugs injectors swapped still always No 3 cylinder  and no DTC so any idea where i can look next compression not measured yet  ???


Title: Re: Audi S3 MY 2000 1.8t APY hesitation and misfire one cyl no DTC
Post by: adam- on November 27, 2013, 03:31:30 AM
I'd say, if you've replaced coils and plugs and swapped the injector, the only thing it can be is lack of compression.

Do all 4 cylinders, then do a leak down test, and bring back the values! :)


Title: Re: Audi S3 MY 2000 1.8t APY hesitation and misfire one cyl no DTC
Post by: P.A.T. on November 27, 2013, 09:12:52 AM
Carry out compression test.

It could be a faulty injector or ECU faulty.


Title: Re: Audi S3 MY 2000 1.8t APY hesitation and misfire one cyl no DTC
Post by: viki300 on November 27, 2013, 10:22:20 AM
compression ok looks like injector problem after all i m gonna clean and test them tomorrow and find out how it goes after that


Title: Re: Audi S3 MY 2000 1.8t APY hesitation and misfire one cyl no DTC
Post by: viki300 on November 28, 2013, 05:07:49 AM
so back to zero i tested injectors and cleaned them they are ok so have to dig further on this then :'(


Title: Re: Audi S3 MY 2000 1.8t APY hesitation and misfire one cyl no DTC
Post by: ddillenger on November 28, 2013, 05:14:50 AM
Does 2000 have an ICM?


Title: Re: Audi S3 MY 2000 1.8t APY hesitation and misfire one cyl no DTC
Post by: viki300 on November 28, 2013, 06:38:34 AM
no


Title: Re: Audi S3 MY 2000 1.8t APY hesitation and misfire one cyl no DTC
Post by: adam- on November 28, 2013, 08:11:11 AM
The plug is wet, which suggests that it's not getting spark.

Are you sure you're getting a FAT BLUE spark on cylinder 3?


Title: Re: Audi S3 MY 2000 1.8t APY hesitation and misfire one cyl no DTC
Post by: viki300 on November 28, 2013, 08:50:00 AM
ok i did put injectors back and runned warm and then measured compression again and suprise No 3 is 9.5 bar others 10.5 so now i want to know where it leaks cylinder or valves i let you know


Title: Re: Audi S3 MY 2000 1.8t APY hesitation and misfire one cyl no DTC
Post by: RS-MAD on November 28, 2013, 12:47:21 PM
ok i did put injectors back and runned warm and then measured compression again and suprise No 3 is 9.5 bar others 10.5 so now i want to know where it leaks cylinder or valves i let you know
9.5 is just fine for cyl to start ,  below 6.5 to say maybe you will have missfire at idle .


Title: Re: Audi S3 MY 2000 1.8t APY hesitation and misfire one cyl no DTC
Post by: viki300 on November 29, 2013, 12:44:59 AM
Yes idle is ok but right after i press throttle let say fast car dies if i just press throttle easy it goes over 4000 rpm it works ok but but all in all all the other cylinders when measured compression pressure stays in cylinder after i remove press gage but on this No3 nothing so it must leak some where or some debris between valve seat


Title: Re: Audi S3 MY 2000 1.8t APY hesitation and misfire one cyl no DTC
Post by: adam- on December 01, 2013, 05:28:29 AM
That's why I said do a cold and warm leak down test.

When it's warm, pull a plug and put a teaspoon of oil down the cylinder, now do a compression test.

If it's higher, it's worn rings, if it's lower, it's worn valve seats.


Title: Re: Audi S3 MY 2000 1.8t APY hesitation and misfire one cyl no DTC
Post by: viki300 on December 02, 2013, 01:13:01 AM
yes worn rings cyl 3 confirmed now  >:(


Title: Re: Audi S3 MY 2000 1.8t APY hesitation and misfire one cyl no DTC
Post by: _nameless on February 06, 2014, 05:32:49 AM
That's why I said do a cold and warm leak down test.

When it's warm, pull a plug and put a teaspoon of oil down the cylinder, now do a compression test.

If it's higher, it's worn rings, if it's lower, it's worn valve seats.
iff the cyl is washed down with gas this would cause low compression too...


Title: Re: Audi S3 MY 2000 1.8t APY hesitation and misfire one cyl no DTC
Post by: viki300 on February 08, 2014, 01:53:10 AM
Hi top piston ring was cut on two pieces changed and its working again ,why it was cut no idea but its working now so that was main thing