182 Engine woes

[Dr Fox]

Evening All,

I'm after a bit of advice, I've done lots of searching but seem to be running out of ideas... My 182 failed it's MOT on a few things, the main one being emissions. It's always had a very lumpy idle and if left idling for a long time, the EML would come on but went off after turning it off and on. Recently, the light has been coming on more often but goes went straight off under load when it got to around 4k rpm. It failed the MOT on emissions to the garage suggested putting some additive in to clean it. I plugged in my cheap OBD reader and using the Piston App, discovered an 02 sensor fault and a misfire on cylinder 3, it was still running fine at this point but the light was coming on more frequently than it used to. I got a 2 part assistive pack from Halfords, put the first bottle in and ran it through a full tank (with 98 RON). I used that tank and then put the second part in, it may well be coincidence but over this time I think it's been getting worse.

What I've done since then:

• Changed the Pre Cat Lambda - 02 sensor no longer a fault but still got a misfire on cylinder 3.
• Swapped injector 2 with injector 3 - still got a misfire on cylinder 3
• Changed the spark plugs - still got a misfire on cylinder 3
• Changed the coil pack - still got a misfire on cylinder 3
• Changed the ignition leads - misfire on cylinder 2
• Put the old number 2 lead back on - still got a misfire on cylinder 2

Next thoughts are that I could switch spark plugs between 1 and 2 to see if it's still spark related but I'm running out of ideas... HELP???

 

[Coops Mk1]

have you unplugged the injector wiring on each injector and checked for engine note change? I suspect you have moved the faulty injector and its taken a while for the clean injector to clear the fault up in cylinder 3 and then taken a few cycles to then take cylinder 2 down if you did all this in quick succession.

 

[STEVE.M]

Cylinder 1 is at the gearbox end on a Renault Clio?
@Dr Fox

 

[Dr Fox]

Yes, cylinder 1 is at the gearbox end on the Clio. It was still running partly on the cylinder so unplugging each cylinder made a difference with each of them but it did turn out to be injector related, thanks!

I first swapped plug 2 with plug 4 - cleared codes and misfire still on cylinder 2
I then swapped injector 2 with injector 1 - cleared codes and misfire now in cylinder 1! Promising news... I swapped it for a spare injector and the problem seems to have been solved! I must have been a bit quick in trying to clear the previous codes so thanks for the pointer! I might have to invest in a more reliable obd reader too...

 

[Coops Mk1]

Tbh usually with these engines it's injectors

 

[Dr Fox]

I may have spoken too soon... As I mentioned earlier, I changed injector number 1 and it was running fine and pulling strongly throughout the rev range on the way to the MOT this morning. Possibly because it was left idling for a quite a long time (it's never liked that) but when they came to doing the fast idle test, it was misfiring and failed the fast idle test.

The lambda reading was 1.13 with a max allowed of 1.03. It was clearly misfiring when he drove it out the garage so when I went out to the car and plugged in the obd, it was misfiring on cylinder 1 again! Turned the car off an on and then it was running fine again! I think it would pass if it wasn't misfiring but as it also failed on headlight washers, I didn't need ask them to retry it there and then.

Has anyone else experienced this after leaving it to idle for a while? I've ordered a set of the NGK plugs from Renault as well as replacement headlight washers that should hopefully be there by tomorrow.

Any other ideas? I'm hoping to get it sorted tomorrow night, MOT'd on Saturday and on track at Silverstone on Sunday but I'm running it of wiggle room!