HELP! Not the usual misfire 1.4 16v

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PoloRuss
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Posts: 6
Joined: Tue Sep 20, 2016 8:27 pm
Drives: 9N 16v 100Bhp
Location: Worcester

HELP! Not the usual misfire 1.4 16v

Post by PoloRuss »

Evening all. My 16v 100 Bhp has developed a Nasty misfire on cylinder 1. I have changed the coil pack on the effected cylinder and changed all the spark plugs to no avail. My next port of call will be the injector on that cylinder. Is that a problem anyone has experienced before? If I clear the codes and take it up the dual track it pulls perfectly but as soon as I pull on the drive and it idles I'm back to misfiring like mad. Any help appreciated!
PoloRuss
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Posts: 6
Joined: Tue Sep 20, 2016 8:27 pm
Drives: 9N 16v 100Bhp
Location: Worcester

Re: HELP! Not the usual misfire 1.4 16v

Post by PoloRuss »

Anyone?
bvs
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Joined: Sat Feb 13, 2016 7:56 am
Drives: 02 1.4s 16v
Location: perth

Re: HELP! Not the usual misfire 1.4 16v

Post by bvs »

Any Fault codes Russ ?
RUM4MO
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Drives: B8 S4 & 6R/6C1 1.2TSI 110
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Re: HELP! Not the usual misfire 1.4 16v

Post by RUM4MO »

I'm guessing that he is getting misfires logged! One thing, as you seem to be thinking about replacing an injector, and they are know to fail sometimes, why not swop a couple to see if the misfire moves cylinders?

Edit:- just one other thing, which engine is it, a "B" one or an "A" one, if it is a BBZ then I'd hope that it is just an injector, if it is an A?? then things could be a bit more serious.
PoloRuss
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Posts: 6
Joined: Tue Sep 20, 2016 8:27 pm
Drives: 9N 16v 100Bhp
Location: Worcester

Re: HELP! Not the usual misfire 1.4 16v

Post by PoloRuss »

I can't remember what code is coming up at the moment, but from what I remember it was a generic misfire code, and I've had egr excessive flow. I have temporarily blanked the egr to see if that made a difference and no difference. My thoughts exactly about moving the injector. I was thinking about removing the injector and running some carb cleaner down it while firing the solenoid. Worth doing? Unfortunately I don't know the engine code but the car is an 02 plate sport 100 if you can tell from that? Cheers
RUM4MO
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Posts: 5859
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Drives: B8 S4 & 6R/6C1 1.2TSI 110
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Re: HELP! Not the usual misfire 1.4 16v

Post by RUM4MO »

Have a look on the build label in the spare wheel well or boot floor, there should be A?? or BBZ on that label, also it should be on the belt cover.

If you try to run cleaner down the injector, make sure that you fire it with the correct signal and not just 12V DC as that could burn it out quickly I'd guess.

Maybe better to just swop them and accept that that injector is u/s if the misfire moves with the injector, but note the fault code first so that you know which ones to swop and then note the new code to make sure that it has changed when you swopped them over.

Edit:- if it is an early build Polo, it could be the A?? engine, if so maybe check the compression first to see if one or more cylinders are low due to excessive bore/ring wear.
PoloRuss
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Posts: 6
Joined: Tue Sep 20, 2016 8:27 pm
Drives: 9N 16v 100Bhp
Location: Worcester

Re: HELP! Not the usual misfire 1.4 16v

Post by PoloRuss »

Right. Compression test comleted. Results are as follows.

Cylinder 1: 140 psi
Cylinder 2: 200 psi
Cylinder 3: 200 psi
Cylinder 4: 185 psi

I am lead to believe up to 10-15% difference is normal. Is 140 psi low enough compared to the others to be causing the missfire? guessing this is a burnt out exhaust valve does this sound correct to you guys?
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