My saturn is a 1994 SL1 SOCH with a manual trans. When I accelerate I starts to hesitate and jump. I does not happen when you barley give it gas but If you accelerate hard it is really bad. You can also feel it surge while crusing. I have replaced the EGR valve and the MAP sensor but still no luck. Any one hav any ideas what could be the problem?

I Also replaced the O2 sensor. Forgot about that one.

have you checked fuel pressure and have you ever replaced the ECT?

no i haventchecked the fuel pressure. Whats ans ECT?

ECT - engine coolent temp sensor

its a known bad part of the S-series engine, it can cause almost any driviblity problem you can think of. good news - it was redesigned in 2001 and the new piece works wonders.

http://www.saturnfans.com/forums/showthread.php?t=24003