2004 Honda Civic, 1.7 liter, manual transmission.

I have been having this issue for several months now where my car has very low speed, the engine hesitates when moving from a stop, and I'll drive at a set speed, like 30 mph, and the vehicle begins somewhat jerking back and forth while moving. Additionally, my vehicle continues to lose speed while going up hill (even when in a low gear) and if I am in gear going down hill, the vehicle will also begin losing speed when it should actually be gaining or maintaining speed.

The local Honda dealership has replaced the MAP sensor, the water pump, and timing belt, which have all been temporary fixes, then the same issue emerges again.

Any ideas on what the issue is?

 

Could be a clogged catalytic converter... Might be time for a test pipe!

 

Have your ignition system checked out.