Clio 182 Misfire

[leon_81]

Hi, I'm after some suggestions, we have a 55 plate Clio 182 with 45k on the clock and it's developed a misfire

We had the fault codes read and it came up with misfire cylinder 1 (I don't remember the code)




Today I have replaced the coil pack and HT leads with brand new genuine Renault items from the dealer. It's still misfiring, but now we get P303 - misfire cylinder 3


Does anyone have any ideas as to what else it could be??? Thinking plugs or possibly injector, but I'd have thought injector fault would have a specific code



Any help appreciated

Thanks

 

[Tony Hunter]

[h=2]Symptoms[/h]Symptoms may include:

• the engine may be harder to start
• the engine may stumble / stumble, and/or hesitate
• other symptoms may also be present

[h=2]Causes[/h]A code P0303 may mean that one or more of the following has happened:

• Faulty spark plug or wire
• Faulty coil (pack)
• Faulty oxygen sensor(s)
• Faulty fuel injector
• Burned exhaust valve
• Faulty catalytic converter(s)
• Running out of fuel
• Poor compression
• Defective computer

[h=2]Possible Solutions[/h]If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.
If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in thecar, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.

This might help.

 

[Jonny1*2]

Injectors or plugs like you said. Remove cylinder 3 injector plug and see if anything changes.

 

[leon_81]

We unplugged an injector and it wouldn't even start? It just turned over for a second or 2 and cut out (like I'd turned the key off)

 

[Jonny1*2]

Was that cylinder 3?

 

[Dan1587]

Swap them, like if the fault is Misfire on cylinder 3 then change the cylinder 3 injector with cylinder 1 and see if the fault code changes to cylinder 1.

 

[barnesautos]

Swap them, like if the fault is Misfire on cylinder 3 then change the cylinder 3 injector with cylinder 1 and see if the fault code changes to cylinder 1.

Spot on , but dont forget to swap cylinder 3 spark plug and swap it with cyl 2 or 4. Not cylinder 1 as no3 injector is going in there.

 

[Dan1587]

Spot on , but dont forget to swap cylinder 3 spark plug and swap it with cyl 2 or 4. Not cylinder 1 as no3 injector is going in there.

Yeah, I always do things one at a time, just to make it easier to work out. But their is no harm in doing it the way above. Just remember what you have swapped.

 

[leon_81]

After plugging the injector back in it won't start at all now...

It turns over to a second and gives up...


It did it when we investigated the first misfire too, but started after it had been left a while. Is there a reason for it? It's like the immobiliser has kicked in

 

[Jonny1*2]

Immobiliser light on?

 

[leon_81]

Yep... Is there a solution for it?

It happeened when we first looked into the misfire but started after we left it 20 mins or so

 

[Jonny1*2]

It could be a wiring fault on the injector plugs somewhere. I'd try and find someone with a few spares or buy some spare bits to rule out a component failure. It sounds more wiring as the ecu wouldn't immobilise the car for a faulty injector

 

[leon_81]

Well it's started (but still with a misfire) a friend of a friend used to be a Renault technician and has all the proper diagnostic tools

He said its showing a specific injector cylinder 3 open circuit now (the mac tools reader we used before just showed misfire cylinder 3)


He said he's certain it'll be a duff injector rather than wiring etc, and that it wouldn't start because the battery was going flat - he put jump leads on it and it fired straight up


Can anyone think of anything we can check to be 100% sure before we fork out for a set of injectors? Is there a test we can do on the injector?

 

[Jonny1*2]

Pm me. You can have one for £13 posted

 

[edde]

Can anyone think of anything we can check to be 100% sure before we fork out for a set of injectors? Is there a test we can do on the injector?

You can get injecotrs checked and cleaned but for the cost often buying another is easier/cheaper