172 Cup Mis-Fire (yes another one!) - anybody help?

[hillclimb_clio]

Hi, have now changed the spark plugs on my 172 Cup & it STILL mis-fires at 2000rpm, seems OK above & below this & seems to accelerate strongly. I'm guessing from reading a few of the other posts on here that the Coil Pack would be the next thing to change then possibly the HT leads? Is it worth upgrading the HT leads to Magnecour or similar? Any suggestions appreciated, cheers in advance!

 

[Fred@BTM]

i'd do the leads first

 

[hillclimb_clio]

i'd do the leads first

cheers, would you use upgraded or OE leads?

 

[ash_s3]

Ive just done mine, went for PerformanceLeads in the end, genuine ones are over £100!

Paid £38 delivered for the Performance ones and the quality seems pretty good.

 

[hillclimb_clio]

ash, did you do that due to a problem with the original leads or did you just upgrade? Have ordered some Magnecor 8mm leads now @ £75 delivered which I didn't think was too bad?

 

[hillclimb_clio]

well have now changed the leads (twice as it goes as the 1st set of Magnecor were faulty can you believe!) and the friggin thing is STILL mis-firing! Guess I'll change the Coil Pack then what if that doesn't work...?

 

[crazycup_racer]

Have you had a diagnosis on it? It would help to see if your getting the same cylinder missfire or multiple cylinders. Try a coil pack, see if anyone has one to try for 5 mins to see, its an easy thing to swap! Failing that it could be an injector fault or even deeper like a circuitboard fault with the ECU. Where are you from mate?

 

[hillclimb_clio]

Have you had a diagnosis on it? It would help to see if your getting the same cylinder missfire or multiple cylinders. Try a coil pack, see if anyone has one to try for 5 mins to see, its an easy thing to swap! Failing that it could be an injector fault or even deeper like a circuitboard fault with the ECU. Where are you from mate?

my local garage plugged it in & it didn't show up any fault codes, they recommended changing the plugs. When that didn't work I took advice as above on this thread & changed the HT leads, upgrading them to Magnecor at the same time. Spoke to K-Tec & they mentioned injectors. Really not sure if its 1 or multiple cylinders mis-firing to be honest - how would you know? I'm in Exeter, Devon.

 

[crazycup_racer]

Ok try this, run the engine at around 2000rpm so the vehicle is missfiring, 1 by 1 remove & reconnect the injector plug. You will soon notice if it makes no differance or drops onto 2 cylinders. If its an injector fault, 1 should not change the engine rpm/note. You can do the same with plug leads but make sure your use a well insulated pair of plyers or you'll get a nasty electric shock.

 

[hillclimb_clio]

Ok try this, run the engine at around 2000rpm so the vehicle is missfiring, 1 by 1 remove & reconnect the injector plug. You will soon notice if it makes no differance or drops onto 2 cylinders. If its an injector fault, 1 should not change the engine rpm/note. You can do the same with plug leads but make sure your use a well insulated pair of plyers or you'll get a nasty electric shock.

OK, how do you remove the injector plugs? Sorry to sound stupid but I'm not really that mechanically minded! Seems strange its only at low revs & doesn't seem to happen all the time though?

 

[ForceIndia]

garage code reader is no use. Mine was hooked up to a snapon code reader, nothing came up. Plugged in an RStuner and a stored lambda fault came up immediately.

 

[James.f]

pull on the buggers quit hard and they will pop out,

 

[hillclimb_clio]

garage code reader is no use. Mine was hooked up to a snapon code reader, nothing came up. Plugged in an RStuner and a stored lambda fault came up immediately.

so I need an RS Tuner then?

 

[crazycup_racer]

OK, how do you remove the injector plugs? Sorry to sound stupid but I'm not really that mechanically minded! Seems strange its only at low revs & doesn't seem to happen all the time though?

They have a small spring clip that you push with your index finger and they will pop off!

 

[pug_92]

^^^ you need to take the fuel rail guard off first think their 10mm nuts, oh and theres 2 of them.

once thats off it's plain sailing

 

[hillclimb_clio]

Shaun @ K-Tec has just suggested trying the TDC Sensor - more likely to be that than the Coil Pack apparently - certainly cheaper to clean that & squirt some WD40 on it anyway! I'll let you know how it goes...

 

[hilldawg172]

my cup is doing something very similar excpet it does it on idle, ocasionally pops and splutters when warm and smells of fuel i do have a decat so i expect a slight smell but since its been doing that its significantly stronger. Any updates on what you have tried would be gratefully apprectaied.

 

[hillclimb_clio]

will try to get the garage to clean or replace the TDC sensor this week, if that doesn't work then I'll get the injectors checked as per recommendations above and/or change the coil pack. Other than that the only other thing that has been suggested is a lamda sensor. will keep you informed & thanks for all your advice