Having hesitation problems off idle and when cruising at 60 mph car is surging

1993 NISSAN SERENA
170,000 MILES
Avatar
KARLANDEE
  • MEMBER
  • 6 POSTS
Installed new egr valve, new bpt valve, new egr solinoid and new exhaust temp sensor. also new oxygen sensor, new plugs, cap, rotor, air filter, new fuel pump and fuel filter, new iacc valve, all new injectors. Problem goes away if I unhook egr valve vacumn hose. It feels like egr is opening too far.
Mar 2, 2012 at 10:53 PM
Advertisement
Avatar
KHLOW2008
  • CERTIFIED EXPERT
  • 41,814 POSTS
EGR seems to be opening too long. Have you tried cleaning the EGR passages?
Mar 2, 2012 at 11:32 PM
Avatar
KARLANDEE
  • MEMBER
  • 6 POSTS
Yes I cleaned all egr passages and checked to make sure I was getting exhaust out of all passages and tubes.
Mar 2, 2012 at 11:58 PM
Advertisement
Avatar
KHLOW2008
  • CERTIFIED EXPERT
  • 41,814 POSTS
Something is telling the computer to keep the EGr opened for longer than necessary and it could be the O2 sensor. If the sensor is not OEM, it can cause such problems.

The other thing to check would be the PCM and MAF. Ensure the TPS is working correctly
Mar 3, 2012 at 12:08 AM
Avatar
KARLANDEE
  • MEMBER
  • 6 POSTS
Yesterday I bought a brand new bosch oxygen sensor and the car has alot more power but still hesitates. I will check the tps and maf tommorow, Thankyou, KARL
Mar 3, 2012 at 12:17 AM
Avatar
KARLANDEE
  • MEMBER
  • 6 POSTS
Just installed new tps and adjusted- car runs better and no surging at 60 mph but still hesitates off idle at stop signs.
Mar 3, 2012 at 1:08 AM
Avatar
KHLOW2008
  • CERTIFIED EXPERT
  • 41,814 POSTS
Did you clean the throttle body?
Mar 3, 2012 at 11:37 AM
Avatar
KARLANDEE
  • MEMBER
  • 6 POSTS
Yes I cleaned it completly.
Mar 3, 2012 at 3:52 PM
Avatar
KHLOW2008
  • CERTIFIED EXPERT
  • 41,814 POSTS
Did you check the ignition timing and valve clearances?

What about the MAF?
Mar 3, 2012 at 4:59 PM
Avatar
KARLANDEE
  • MEMBER
  • 6 POSTS
Timing is set to 10 degrees and vavles have been adjusted, MAF is next on the list. Thankyou for all your help, KARL
Mar 3, 2012 at 6:18 PM