When I accelerate from a stop, at times the engine (603) seems to have lost much of it's power. It will run smoothly (but increase revs slowly) and then suddenly increase power to normal levels. This happens around 3000-4000 rpm, from what I've noticed.

I'm wondering if the injection pump timer is the cause of this. It looks like a centrifugal advance to me, which should allow the injection pump to advance the point of injection at higher rpm. It seems like mine might be sticking, and then suddenly releasing at higher rpm. It's not like the turbo spooling up, since the power increase is instant. Has anyone heard of these timers having a similar problem? Could there be another explanation for the sudden, instant surge in power?

While anything is possible, the SDL is typically "sedate" at all rpm's less than 2400, especially if the ALDA is at the factory setting. The '86 is exactly in this condition and it won't go anywhere until the revs get up into the turbo range (2600 and up). Then, the vehicle comes alive.

I'd first attempt to adjust the ALDA to provide it more fuel across the rpm range. Everyone who has attempted this has been surprised at the performance improvement at lower speeds.

I need to do it myself. It's number 8, or so, on the list.

I've had the car for almost 2 years, and cranked up the ALDA shortly after I bought it.

The problem with the lack of power is intermittent (which makes me think that the ALDA is getting a boost signal at least most of the time, which should mean that the line is not plugged) and has only occurred recently.

I guess I could turn up the ALDA a bit more. I initially had it turned up so far that I could chirp the tires from a standing start, before I backed it off to a more reasonable setting. I still think the recent surge in power has something to do with the injection pump timer.

The '86 starts to behave in that fashion every time I run it too low on fuel. Just has no power........won't climb a hill at 70 mph........

After refueling, it regains it's normal power levels within 50-100 miles or so.

One of these days I have to drop the tank screen.