SLK 200 171 Check Engine Light

[chrisslk]

Living in Gloucester has meant we have seen alot of rain recently and as such saw me being stuck in work for a 24 hour period. When i got into the car the following morning, she started fine but ran very rough (as though misfiring or missing one cylinder?). Thinking perhaps some water had got into the engine bay, i did as quick a check as i could to find any possible loose leads or signs of water damage. Now bearing in mind the car was driven into work fine and i didnt go through any large puddles and the water did not go past the rim of the tyres, i cant see how this could have had an effect. That said, after turning the engine off for a while i came back to start her again and she is fine. Only problem is the red check engine light is on ??? Now does this mean an expensive drive to the local stealership? or is it possible to reset the light?

Many thanks.

 

[BlackC55]

It has logged a missfire fault.

Number 1 cylinder is prone to fill with water and cause a missfire.

 

[chrisslk]

It has logged a missfire fault.

Number 1 cylinder is prone to fill with water and cause a missfire.

Thanks Black, what is the course of action to rectify?

 

[fredfloggle]

I would have thought if it had enough water to cause a persistant missfire it would bend a rod ?

 

[BlackC55]

Sorry should have been more specific.

The spark plug hole fills with water and causes a missfire. Remove the plug and investigate.

 

[fredfloggle]

Sorry should have been more specific.

The spark plug hole fills with water and causes a missfire. Remove the plug and investigate.

Now clear - however make sure you clear this water out before you remove the plug, look down the hole, put the plug back in and hydraulic the thing .

Used to happen years ago on radials - guy would turn over a big radial and feel the bottom cylinder lock up - a few guys thought that by turning the old girl backwards that the would expel the oil - they were half right , it was expelled but back into the inlet manifold . The engine would turn over OK but a great big glug of oil would get sucked in on start up making it really quite ill .

Completely off topic, but there we go .

 

[chrisslk]

Thanks for the info guys. After further inspection i managed to clear the fault, simply by running the engine for a while. Turned it off then started again and problem has gone. Engine diagnostic light was still on, but after reading some replies of the ferrari forum, a couple more attempts to starting cleared the fault. Worthy to note the water fault though, so thank you again for you help.