Clio Sport xxx
....at least I think it's a misfire! I'm after some help / advice to diagnose please 
Car is a 53 plate 172, done 100K miles with FSH.
I've owned the car since 2006 on 36K and it was totally standard, but even when I first got it, I noticed that it never had a smooth idle. I later read that a slightly lumpy idle is normal for this engine, even when standard. Is this right? You could only tell if you put you ear close to the exhaust, but the constant puuuuuuuuuuur got interrupted at regular intervals (say every 5-10 secs) by a slight parp / break in the purr.... does this sound normal?
Anyway, in the last couple weeks I have noticed, what I assume to be, a more definitive misfire. It only seems to occur at low load and very low throttle. It is most noticeable in 1st and 2nd gear, e.g. when in slow moving traffic. If I am coasting very slowly on the over run, in 1st or 2nd, and I then apply a very small amount of throttle, the acceleration is hesitant and slightly jerky. It seem worse in the lower rev range, say 1.5-2.5K RPM, but I have got it to happened when using minimal throttle at 3-4K RPM in 2nd and 3rd gears. Then as soon as you apply more than half throttle, the misfire seems to clear up. If there is any power loss on full throttle it is minimal and barely noticeable. Also, idle is now slightly more lumpy then before and the slight parps / break in the purr more pronounced.
A funny thing happened this morning too which I've not had before.... because I now have a de-cat pipe, my emissions light is permanently on, which I’ve got used to. I popped out this morning in the car, drove the 30secs up the road to the traffic light and came to a stop. Idle was still at 1.3K'ish RPM and lumpy as the engine was still cold. I then noticed the emissions light was flashing!?!? As soon as I pull away it goes back to constantly on. Anyone know what a flashing emissions light means?? I assume it must be related to the misfire and not just a coincidence...?
Mods include de-cat pipe (with both lamda's still fitted) and BTB full s/s exhaust, panel filter, ported/CNC matched inlet manifold, cams and re-map. All mods and last cam belt done in 2007 (I think), so the cam belt is due in next service later this year.
Anyway, thanks for reading and any help much appreciated.
Car is a 53 plate 172, done 100K miles with FSH.
I've owned the car since 2006 on 36K and it was totally standard, but even when I first got it, I noticed that it never had a smooth idle. I later read that a slightly lumpy idle is normal for this engine, even when standard. Is this right? You could only tell if you put you ear close to the exhaust, but the constant puuuuuuuuuuur got interrupted at regular intervals (say every 5-10 secs) by a slight parp / break in the purr.... does this sound normal?
Anyway, in the last couple weeks I have noticed, what I assume to be, a more definitive misfire. It only seems to occur at low load and very low throttle. It is most noticeable in 1st and 2nd gear, e.g. when in slow moving traffic. If I am coasting very slowly on the over run, in 1st or 2nd, and I then apply a very small amount of throttle, the acceleration is hesitant and slightly jerky. It seem worse in the lower rev range, say 1.5-2.5K RPM, but I have got it to happened when using minimal throttle at 3-4K RPM in 2nd and 3rd gears. Then as soon as you apply more than half throttle, the misfire seems to clear up. If there is any power loss on full throttle it is minimal and barely noticeable. Also, idle is now slightly more lumpy then before and the slight parps / break in the purr more pronounced.
A funny thing happened this morning too which I've not had before.... because I now have a de-cat pipe, my emissions light is permanently on, which I’ve got used to. I popped out this morning in the car, drove the 30secs up the road to the traffic light and came to a stop. Idle was still at 1.3K'ish RPM and lumpy as the engine was still cold. I then noticed the emissions light was flashing!?!? As soon as I pull away it goes back to constantly on. Anyone know what a flashing emissions light means?? I assume it must be related to the misfire and not just a coincidence...?
Mods include de-cat pipe (with both lamda's still fitted) and BTB full s/s exhaust, panel filter, ported/CNC matched inlet manifold, cams and re-map. All mods and last cam belt done in 2007 (I think), so the cam belt is due in next service later this year.
Anyway, thanks for reading and any help much appreciated.
