Toyota Repair: 1990 Toyota Cressida, 1990 toyota cressida, 7mge engine

Question
1990 Toyota Cressida. 7MGE  engine. 198,000KM.
Not sure about the transmission. It's original.

When I step on the gas, the car feels like it's going to accelerate briefly. Then it feels like it not going to go for maybe 30 seconds. Then it drives fine. The overdrive light flashes once continiously after this. Sometimes it goes off by itself when the car reaches 100 KM per hour.

Can you point me to what to check? Is it the transmission? Or is it a vacuum hose or a sensor?

There is some residue where the house from the camshaft cover enters the the air flow for the injector system. It's right beside the trottle position sensor.

Thanks for you help.

Answer
The O/D light flashing indicates there is a problem with the elctronic control system of the transmission, although this is an early OBDI system a diagnostic code can be retreived to see what the trouble area may be, so I suggest that you have a toyota dealer retreive the trouble code from the computer.
The camshaft/valve covers are known to leak, causing oil to collect inbetween the cam covers where the spark plugs are located.