98mercslk

Hi all, I have searched most forums for an answer to this problem, so anything you can advise me is appreciated.

I have a 98 merc slk R170. Each time I start it, it works fine for approx 20 miles. When it changes gear a couple of times, say at a roundabout, it then stutters and then chuggs along. It still changes gears fine and responds to the throttle, but it just "chuggs". If I pull over and turn ignition on and off, it works as normal for another 20-30 miles.

Any ideas ?
I know a mechanic who has a decent diagnostics, but nothing comes up. Could it be the cat ?

Any help appreciated !

Thanks
Nick

bazzle

This what I would do
First thing to do is to clean maf with crc maf cleaner.
Second thing is to resolder joints on K40 pdb.
Third thing is to change air and fuel fitlers

Bazzle

98mercslk

Thanks Bazzle. I was hoping you would answer, I forgot about advice I have read before on the K40 relay. Do you still have any photos you could attach on this post ? (I have googled and can see you have posted on other sites, but I am not a member so cannot view your attachments)
I would probably try the K40 first as it does sound more electrical than anything else.
Would the Maf be an issue all the time if it was at fault ? Thanks again !

Nick

bazzle

Not sure, these cars sometimes just need each item checked.
Join Benzworld and read Tech stickys there. Take you about 30 seconds.
http://www.benzworld.org/forums/r170-slk-class/
Now if you said it stopped completely and then restarted after a bit I would of said Crank sensor mounted on top of bellhousing.

Bazzle