I have a 94 nissan altima that I recently had drivability problems with jerking and not being able to go over 20 mph. I replaced the distributor and coil it runs a little better but not 100%. I had to almost fully advance the distributor so that it has more power. What else can I look for?

I have a 94 nissan altima that I recently had drivability problems with jerking and not being able to go over 20 mph. I replaced the distributor and coil it runs a little better but not 100%. I had to almost fully advance the distributor so that it has more power. What else can I look for?
Check the base idle speed and ignition timing. If the base idle speed (IACV-AAC valve held fixed) is out of specification (low), adjust to specification. This valve may be sticking or the throttle housing may need cleaning.

Check fuel delivery/volume. Fuel may be present but not be enough to provide power.

A countermeasure ECM and coolant sensor have been developed by the factory which provides a better air/fuel mixture ratio during engine starting.

. Ensure you are using OEM spark plugs that are in good shape.
. Check/replace the Ignition Control Module.
. Ensure MAP Sensor and associated hoses are tight and in good shape.