New owner 172 missfire:(

[m20b27]

I've posted up as my 172 (2001) has developed a miss-fire..

I'd given the car a clean up inc the engine bay, drove home (70 miles!) no problems.


Next morning, girlfriend takes the car to work and I get a call to say "car is stuttering badly, and EML is flashing"

According to the RAC it was showing a missfire, but not giving a code for cylinder.


Get it home, sort out some water down by the plugs, put it all back together and still have the same issue.


Idle is rough and surging, with the occasional pop

car stutters under load, getting better higher in the rev range.



I'm suspecting wither plugleads/coilpack or injector.

Tried to order new leads, but have been asked what engine code I have- I know its an f4r, but not if its a 730 etc.

The autoparts shop say they have leads suitable for a 730 and a 736 (the same part)

but are the leads different between engine codes? I'd really appreciate your info on this!

I dont want to pay for the wrong leads to be ordered.

I've already PM'd Adam (t21ads) for info on what engine code is fitted so I can order plug leads)

thanks

 

[Andyrg@ ClioTurbo]

leads as far as i am concerned are all the same

 

[m20b27]

leads as far as i am concerned are all the same

Excellent, thanks a lot!

New leads tomorrow then!

 

[Daniel]

Plugs leads and coilpack would be my first change. Don't cost a lot and it's always nice to renew the lot at once because if you don't, sods law says that something else will break next weekend! lol.

 

[Dom67]

I had the same problem on my 182 soon after I got it... Or similar anyway. Coil pack was fine, ht leads were fine, plugs were good too. Turned out to be a drippy injector on cylinder 2 although this was not picked up by a diagnostic, only the misfire was.

Before ordering new leads/coil pack/plugs I'd have a look at the plugs to try and find out which cylinder the misfire was occurring in. The offending cylinder should cause coking on the plug so this can be cleaned up to avoid needing new plugs if the current ones are still relatively new and ok. If the leads are showing signs of corrosion or if thecoil pack/ plugs are old and knackered it's probably worth replacing the lot as Daniel says, but, if its an injector issue this alone will only be a temporary fix.

 

[m20b27]

Plugs leads and coilpack would be my first change. Don't cost a lot and it's always nice to renew the lot at once because if you don't, sods law says that something else will break next weekend! lol.

Cheers, Just had confirmation its a F4R732 from Adam, and he's also confirmed the coilpack/plug leads are the same for all the 172 and 182 as far as he's aware. So I think I'll get plug leads and coil pack first

I had the same problem on my 182 soon after I got it... Or similar anyway. Coil pack was fine, ht leads were fine, plugs were good too. Turned out to be a drippy injector on cylinder 2 although this was not picked up by a diagnostic, only the misfire was.

Before ordering new leads/coil pack/plugs I'd have a look at the plugs to try and find out which cylinder the misfire was occurring in. The offending cylinder should cause coking on the plug so this can be cleaned up to avoid needing new plugs if the current ones are still relatively new and ok. If the leads are showing signs of corrosion or if thecoil pack/ plugs are old and knackered it's probably worth replacing the lot as Daniel says, but, if its an injector issue this alone will only be a temporary fix.

Thanks for that, I'll have a look at the plugs when fitting up the leads. I see injectors are not too expensive- Is replacement difficult?

 

[m4tt274]

mine developed the same problem last night.
Had new plugs and leads about 500 miles ago so am suspecting coil pack.

 

[m20b27]

mine developed the same problem last night.
Had new plugs and leads about 500 miles ago so am suspecting coil pack.

Sorry to hear that mate!

I'm gonna get leads and coil pack ordered up I think

 

[Dom67]

IF it is an injector issue then changing one is not too hard, no. Use Renparts or the classified section on here. New injectors from renparts are something like 35 quid iirc and if i were you i'd get paid up as a member and search the guides or just the forum for advice so you can decide if it's something you're willing to do yourself... but it is an easy enough job!

Before you order new plugs have a look at the current ones and have a look in the service history (if present) to find out when they were last changed. it may be that cleaning up the offending plug will temporarily solve the problem. I nearly ordered new plugs before i found the injector fault, but all that was needed was a good bit of carb cleaner to get the buildup off the plug in the offending cylider and the car ran like a beaut after... but the injector still needed to be changed!

 

[m20b27]

IF it is an injector issue then changing one is not too hard, no. Use Renparts or the classified section on here. New injectors from renparts are something like 35 quid iirc and if i were you i'd get paid up as a member and search the guides or just the forum for advice so you can decide if it's something you're willing to do yourself... but it is an easy enough job!

Before you order new plugs have a look at the current ones and have a look in the service history (if present) to find out when they were last changed. it may be that cleaning up the offending plug will temporarily solve the problem. I nearly ordered new plugs before i found the injector fault, but all that was needed was a good bit of carb cleaner to get the buildup off the plug in the offending cylider and the car ran like a beaut after... but the injector still needed to be changed!

Brilliant thanks,

I've ordered a 2nd hand Coil pack and leads-should be here in a day or two.

Are the plugs removed with a 16mm socket, or a larger one?

I can get them out and cleaned tonight.

 

[Dom67]

Yeah just a standard 16mm spark plug socket mate. Let us know how you get on later!

 

[m20b27]

Well, got the sparkplugs out (used it as an excuse to buy a new socket set )

Gave them a clean up on a wire wheel and popped them back in.

Reconnected the battery and started it.


Immediately was running better, and a few short runs to let it re-learn ecu settings, then out for a 5 mile run.

Car is now back to normal


Still,gonna do the plugs and leads as preventative maintenance-as both sets look past their best.


Thanks to everyone for all the help

 

[m20b27]

New leads and coilpack done,

New plugs arrived today- hope to have her all sorted by tomorrow evening