I need help please.. Motor swap gone bad..

[Thee 240sx Owner]

Ok i have an 89 240sx... Manfactured in 2/88... Now i was told and seen some information bout the new motors when 240's were made were high compression... Now i recently swapped it for an 89 motor of later date becuz my current motor had spun a bearing... and everything was installed correctly and the only thing that was changed was the egr valve wasn't reinstalled but was capped off... The motor fired right up but has a rough idle to it to were it shakes it alot.. but reved up it seems fine.. In gear.. it feels like is had no power whatsoever.... Now i have no idea of the condition of this newer motor but it dosn't make any noise while running except for rocker arms sound a lil rusty... but i was wondering if maybe the ecu needs to be changed out cuz of the different motors now... and if anyone may have any suggestions as to what this maybe.. If its not the ecu.. my best bet is valve timing.. which i fear it maybe... thanxs for your help...

[[s3]]

Should be the same KA24E motor, unless you put in a later 16v motor..that might screw things up.

ECU does not need to be changed. You might want to check out your timing with a gun, check also for vacuum leaks and the usual things like bad maf sensor connections etc etc.

[lbrowne]

Like [s3] said, check your timing. Also check your MAF connections too.