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clunk clunk chuck chuck clunk

1278 Views 5 Replies 3 Participants Last post by  Yal
That's the noise my engine makes when I start it (only when warm after car has been sitting for 10 min)

its missing, idling at 400, runs on 2 cyl, goes clunk clunk... when I revv it, it becomes smooth & occasionally runs rough in D when waiting at the lights

figured timing chain is stretched, changed it, new ignition wires, new plugs, cleaned the idle valve (it was quite clean to begin with)

I am running out of ideas

only thing I can think about is a dirty fuel distributor... when I cracked loose the bolts on top of the fuel distributor (to see if fuel was flowing), on 2 of them, the gas that came out was brown in colour and colourless in the other 4. I cant exlain the brown gas [?]
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Its not your FD. My guess would be a bad EHA or fuel regulator. I would get an EHA test harness from the dealer, a multimeter that reads duty cycle and test away. Otherwise you are just throwing money at the problem and it will get expensive! Even a cheap fuel presssure tester would give you some valuable info.

Thanks.. do you sell MB parts? Do you have a website with parts list and pricing? (unrelated to this, but do you sell euro lights?)


Pardon me but what is an EHA? How do I test this? I dont have a manual for my car so unless I am given specific instructions, the most I can do is remove the air cleaner and look at the FD assembly and scractch my head
just did some search in the archives under "crud" & "dirty distributor" and found some links suggesting to how people cracked the top bolt on the fuel dist to let the brown struff flow out and then their car was as smooth as silk..

gonna give it a try and see what happens
EHA is short for electro-hydraulic actuator, it is the small box attached to the side of your fuel distibutor. It has a electronic connector that runs directly to the control unit. This is the part of the fuel dist. that makes adjustments and compensations for different engine loads and speeds. It works at real time speed to adjust flow and or mixture.
Like redwood says this box is crucial to the operating of the FD system. There is a good description of how to test it on , its easy and you can tell a lot about your car from it. is a great article by Steve B about it.
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