EGR - Black Exhaust and Low Power

[bikeregg]

I recently purchased a 1988 MasterAce with the 2CT, 2.0 Turbo Diesel engine. It started great and had good performance when cold but, once it warmed to operating temperature (and the EGR Valve opened), performance went way down and thick, black smoke poured from the exhaust. When I say "poor performance", I mean that there was barely enough power to move the van from a stop and it would be 15 - 20 seconds before any real acceleration.

After a bit of research of other people's experience, I figured the EGR was killing the engine performance. The EGR is meant to reduce NOx emissions by lowering the combustion temperature. After more research I learned the EGR causes approximately 10% reduction in horsepower and 3-5% reduction in fuel economy. The 2CT engine is rated at 80 horsepower but I think it lost more than 10%, at least at low rpms.

I fabricated a restrictor plate that would block the EGR Valve from pouring exhaust gases into the intake. The difference was immediate. The only time I see any smoky exhaust in on a hard acceleration and power is much improved.

[Duke]

Does your van have an automatic or manual transmission. I remember reading that only the auto's had EGR. I would be interesting in seeing pictures of what you did if you have any.

[bikeregg]

Does your van have an automatic or manual transmission. I remember reading that only the auto's had EGR. I would be interesting in seeing pictures of what you did if you have any.

It's an automatic. I did not take any pictures, sorry. The EGR connects to the intake manifold by a two-bolt flange. I made a plate that fit that flange. I used a band saw to shape the plate, drilled out the bolt holes, then cut the ends open for the bolt holes to make lining everything up easier. A poor drawing has been attached. I didn't replace the gasket or put any other sealer on it and it seems to be working quite well.

[Ace MM]

I stuffed a BB in the vac line that opens the valve.

[bikeregg]

I stuffed a BB in the vac line that opens the valve.

I though about simply disconnecting the vacuum line or the electrical connector. For some reason, I chose a more complicated solution.