Misfiring in cylinder 2?

[twodoctors]

Hi all,

New to the forum, and only picked my RCZ in 200bhp up yesterday. Bought it privately. When I test drove it, 3 days ago it was fine. Delivered by the seller to my house about 30 mins drive away. All went well.

Then when I took the car out for a spin, disaster struck! Engine warning light. Drove home straightaway as I was only about 1 min into the drive. No limp mode. Called the AA as I have home cover. OBD said misfire in Cylinder 2. The car went back to normal. Drove for about 40 mins after that, trouble-free.

Today drove it to work, no problem. Drove it back, and the engine light popped up on starting. I already had an OBD, and my mechanic was closing, so decided to drive home and diagnose it myself. During the drive, light came on a few more times, and went to limp mode. 4 code recorded, 2 were manufacture only P1339, and 2 says cylinder 3 coil something. Reset it, and start the car again, hoping for the same result as last night. No joy. Rough idling, so 1 cylinder must be misfiring.

Got some coils and spark plugs on order. For whatever reason I swapped the coils rounds hoping to see if the OBD will give me a different reading. Now it says P1336. P1339 and P1340.

Can it all be down to a faulty coil(s)? Or is something else brewing underneath it?

Bought some cheap ones from Amazon as a temporary measure. Hopefully the NGK ones will arrive by Monday.

:-(

Adrian

 

[Charlie1875]

Hi mate, if the faults are moving when you change the coils round it may be a coil issue, first thing I would do is remove the cheap coils and bin them, it could be the start of a hpfp issue

 

[twodoctors]

Thanks.

Those are Bosch in there. Getting some cheap ones to get me moving until the NGK arrives.

I would like to think that it's just bad luck rather than being sold a lemon...

 

[Verminator]

Yes totally agree with Charlie 1875 as it's got all the tell tail signs of high pressure fuel pump very common for the THP engine if you look back on some of the previous posts you can see that other members have had the same problem....
Drive safe and stay lucky
Les n Co

 

[twodoctors]

Oh dear... could I have spotted it when I bought it? Everything was normal (to a lay person) when I test drove it.

Is this a DIY fix if the coil pack / spark plugs doesn't resolve the original issue?

 

[twodoctors]

The plot thickens for me.

My spark plugs spanner arrived. So I somehow have 2 Bosch and 2 NGK sparkplugs. Someone will need to tell me which cylinder is which. The 3rd (counting away from the belt) has a usually wide spark gap, even to my untrained eye.



Compared to the other Bosch in cylinder 4 or 1.



The plug themselves are all looking ok. The NGKs looked normal to me. Not burnt, no carbon or oil. How did that happen?

New NGKs coming on Monday. Chinese coils hopefully coming later. It might just be plugs problem only...

 

[twodoctors]

Just googled it. Gap should be less than 0.9mm. The incorrect one is more like 2 to 3mm. That probably put stress on the coil, leading to premature failure.

Hopefully the HPFP is ok. Someone did clean the engine compartment so everything is shiny, including the HPFP. Also noticed 2 bolts missing in odd areas, which I didn't spot initially. Was distracted by how clean things were inside compared to my 11yo BMW F31.

My question really is how did the people who serviced the car miss that? Surely it cannot be a malicious attempt to sabotage someone's car to generate more future work, right? And mixed spark plugs? Really?

 

[Charlie1875]

I would change the spark plugs as they get so hot they sometimes don’t last that long

 

[twodoctors]

I would change the spark plugs as they get so hot they sometimes don’t last that long

That's coming on Monday. NGK Coil and plugs set

 

[twodoctors]

Fixed!

The chinese coils arrived this afternoon. Checked the gaps for each spark plugs again. It's around 0.7mm which is lower than spec according to Google (but that might be for the 156bhp version). Anyway, corrected the one that was out. Changed to all chinese coils. Cleared the code. And it is back to normal again!

Will be using all NGK when they arrive. It's only day 3 of ownership. I hope this is it, and it will be trouble-free from now on.

Also managed to change most of the bulbs to LEDs. Bought the wrong one for DRL, which is not working anyway for some reason. No warning light for that.

Thanks all!

 

[Charlie1875]

I would never fit cheap Chinese parts especially coils that get very hot, but fingered crossed for!

 

[twodoctors]

I would never fit cheap Chinese parts especially coils that get very hot, but fingered crossed for!

It's only for a few days!

 

[gwest]

Bear in mind that there are fake NGK spark plugs available online. The fake one is on the right- it lasted a couple of months

 

[twodoctors]

Bear in mind that there are fake NGK spark plugs available online. The fake one is on the right- it lasted a couple of months

These look pretty genuine to me... Just waiting for the plugs now.

 

[Pedro]

If your coil packs are faulty they will destroy the plugs & vice versa like mine did the heat generated by malfunctioning is the culprit

 

[twodoctors]

If your coil packs are faulty they will destroy the plugs & vice versa like mine did the heat generated by malfunctioning is the culprit

I corrected the spark gaps on the existing plugs before installing the Chinese coils.

Everything has arrived now. Just need to find time to put them all in.

Thanks all for your advice.