what would cause engine to idle rough,cuts off but will crank back on 2003 Suzuki Aerio

replaced bad mass a/f sensor,cleared codes.got running & no codes returned.low & rough idle,cuts off.ck fuel pres. & found it was too low @ injectors.replaced pump,still have idle problem.runs great above idle.also has new s.plugs,air filter,cleaned intake.drives good above idle,high speed no problem.still not codes.a BIG thanks for any help,jimmy.email jhstatham@gmail.com

by in New Bern, NC on March 23, 2013
Get Your Car Fixed at a RepairPal Certified Shop.
We certify shops based on expertise, quality work, and verified customer reviews
1 answer 1 comment
ANSWER by , March 23, 2013
you've already eliminated alot of possibilities. look to exhaust system. possible cat. conv. higher rpm forces air through with more pressure. possibly to much back pressure at idle.
COMMENT by , March 24, 2013
thanks,that was on my mind.i'm back after resting my brain w/fresh start.i'll let you know about this.i also had another person told me possibly the ecm,but don't have anyway to test.i'll ck the exhaust 1st & if that's not it,i'll look for ecu to borrow & test.thank's again & will send reply.jamesh50