Mercedes-Benz Forum banner
1 - 4 of 4 Posts

· Registered
Joined
·
19 Posts
Discussion Starter · #1 ·
Hi, i have a 1987 MB 300d turbo six cylinder. I put new bosch injectors nozzles and calibrate each one to 2000 psi. The car after i started has a black smoke on iddle and a lot if i step on the fuel pedal. At the beginning the injector 1 was at 2100 psi and the injector 3 was at 1800 psi then i switched the nozzles and now all are at 2000 psi. I put an after market air filter and took out and installed the original, because it was smoking a lot more. With the after market air filter smoke like 60 percent more i do not know why. Today i was checking the vacuums i found one of the hose cracked and changed, but after that the car does not shut off, the one that i worked was the vacuum amplifier swithchover valve. I know that the the stop unit shut off the engine, but when i put the key the lever on the pump does not move. But now the most important to me is the black smoke, it is pure carbon coming out of the muffler. I put the engine on the 15 atdc and verified if the lug of the governor was in the center of the hole, all looks okay to me. I never work with a diesel engine before, but i like to learn reading the manuals and doing the work by myself, knowing the car i have in case of something happen on the road.
 

· Registered
91 420 SEL, 87 300D, 92 190E
Joined
·
10 Posts
Check your EGR valve. If it is failed open, or the vacuum system that operates it is faulty and allows it to remain open when it should be closed-like at idle-it'll smoke, and in cold weather start-ups, may not even allow the engine to run. The EGR failure cools the exhaust sufficiently to keep the turbo from spinning up enough to work correctly. Plugging the vacuum line to the EGR may keep it closed. You're on the right track if it suddenly starts running cleaner and has increased power. I went the nozzle route several years ago, and had no improvement in smokey exhaust. Plugging the EGR vacuum line made a new car out of my 300D. Cheers,
 

· Registered
1987 300TD, 1988 230TE, 1979 VW Westfalia
Joined
·
60 Posts
if you installed an aftermarket air filter, did you bypass/eliminate the airflow meter that is upstream of the filter housing? this afm is part of the EGR system so it could be related to the post above.
 

· Registered
Joined
·
19 Posts
Discussion Starter · #4 ·
if you installed an aftermarket air filter, did you bypass/eliminate the airflow meter that is upstream of the filter housing? this afm is part of the EGR system so it could be related to the post above.
I did not eliminate or bypass the the airflow meter. That meter is the one under the air filter canister? How do i eliminate it? I found out that the 5 and 6 injectors are leaking antifreez, and you know what that mean. Lucky me that i have another (#14) head ready to install. Last night i order all the gasket to do this job. Any suggestion will be appreciate and thank you.
 
1 - 4 of 4 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top