'87 190D -- OM602-911

While looking for vacuum leaks that might fix an a/c problem, I discovered the VCV on my injector pump is not sending vacuum to my vacuum amplifier (and from there to my tranny). Max adjustment of VCV had no effect. I'mgoing to install a new one -- but, hey, how tricky a job is this? Do I justtake the two bolts out and pull it off -- or is there more? Any advice would be much appreciated.

Also, EGR question: there's a lot of carbon/soot in my air filter housing
due to the EGR introduced exhaust gases. The EGR isn't required down here,so if I wanted to disable it, what would I do? I've read about inserting a BB in the vac tube to EGR. In the case of this 602 engine,though, there's also a pressure control flapper valve between the air filter and the EGR pipe into the housing. This flapper valve opens and closes electrically and pneumatically, based on several inputs (>40 degrees, 1250 -
2500 RPMs, accelerator position, etc).

Given this, my question is, if I BB-disable the EGR valve, should I also
unscrew and detach the little flapper from its stem, thereby letting the air
flow freely through the filter regardless of the temp/RPM/etc. What do you
think? Best advice gratefully accepted.

Thanks,

> Chip Hannay
> '87 190D 155K
> '84 300D 205K
> Austin/Dripping Springs, Texas

The key is to make sure that the vacuum is getting into the system in enough volume. I have seen where there was enough vacuum when the gauge was on, but not enough volume. the little filter for the vacuum system was partially clogged. It is about two inches from the pump and is clear plastic.

The disableing of the EGR and Intake valve will work as you mentioned.

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Donnie Drummonds
1992 500E (very soon I hope
1981 280GE SWB
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