eratic idle and stalling

[jmc1]

this is my second post after great sucess with my first. Any help, hints or ideas will be greatly recieved. My 1995 C280 Sport Auto has developed a tickover problem ie. once warm it dosen't like to. iIt bounces up and down the revs from about 500rpm to 1000rpm and when you stop at lights or junctions it can sometimes stall. my thoughts are either a dirty airflow meter or dirty throttle body. Normally i would just fix this at my liesure asking advice along the way but the wife drives the cars mostly and im getting lots of grief.
thanks

 

[SNAP ON]

I would start at the airflow meter............

 

[neilairman]

idle problem

inside the throttle body is a butterfly type flap.
when you put your foot on the throttle this flap opens to allow more air intake
when the flap is at rest there is a small allmost invisible gap allowing air past the butterfly.
over time this gap gats sealed whith genral gunk.
open the flap and clean the area where the flap comes to rest and clean the edges of the flap as well.
its fiddley but should work.

 

[SNAP ON]

Brake fluid is one of the best things to clean this with...

 

[c320]

inside the throttle body is a butterfly type flap.
when you put your foot on the throttle this flap opens to allow more air intake
when the flap is at rest there is a small allmost invisible gap allowing air past the butterfly.
over time this gap gats sealed whith genral gunk.
open the flap and clean the area where the flap comes to rest and clean the edges of the flap as well.
its fiddley but should work.

anyone know where this is on a c320?

 

[television]

Injection

I feel sure that your car has fuel injection and not a carb. The most common fault on your car is the MAF sensor and will give the problem that like yours.
there will be a fault code will be stored in the car, have it read and you should find the MAF filter on its last legs. Easy to change,on top of the engine

Malcolm

 

[SNAP ON]

I feel sure that your car has fuel injection and not a carb. The most common fault on your car is the MAF sensor and will give the problem that like yours.
there will be a fault code will be stored in the car, have it read and you should find the MAF filter on its last legs. Easy to change,on top of the engine

Malcolm

Your correct,that car is fuel injected.

 

[c320]

Well i feel a little embarrased!

Are theer any known additives that can be used then? to clean the injectors? in a petrol c320?

 

[SNAP ON]

Dont worry,im sure others make bigger mistakes..lol.

 

[television]

Well i feel a little embarrased!

Are theer any known additives that can be used then? to clean the injectors? in a petrol c320?

Yes,you buy tin at the petrol station pour it in the tank and they all get clean and yes it works

Malcolm

 

[c320]

Yes,you buy tin at the petrol station pour it in the tank and they all get clean and yes it works

Malcolm

Hi malcolm,

sorry what is tin?

what brand would you use? or would you only use an mb type additive?

 

[television]

Sorry, A tin of injection cleaner, STP is good, not sure if Red X is still made but the STP is fine.
Malcolm

 

[SNAP ON]

Have a look here..http://www.wynnoil.co.uk/

 

[jmc1]

thanks

the throttle body was my main thought as i have seen this before on other cars.
but you guys have more experiance with mercs than me. also the air flow meter can also get dirty and this can be cleaned off using a contact cleaner, some manufactuers recomend this is done during a service. this is the second time i have ever used one of these forum things and its nice to know that you can ask questions about your car without feeling like a tube and know there is people out there willing to give advice for free.
thank you very much those that replied i am very greatful and i will let you know what the prob was.

JMC 1

ps my next question may be about my gearbox so be ready ha ha ha

 

[dogsbody]

Injector cleaner usually used in diesels is exactly that ...it cleans injectors. It works quite well on petrol injectors, and it is not commonly realised that petrol injectors need cleaning just like diesel ones...