How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask rpmdiag Your Own Question
rpmdiag, Tech and Instructor
Category: Nissan
Satisfied Customers: 7722
Experience:  Since 1975
Type Your Nissan Question Here...
rpmdiag is online now
A new question is answered every 9 seconds

2000 nissan sentra gxe automatic qg18de codes po420/po430/p0505

Customer Question

2000 nissan sentra gxe automatic qg18de codes po420/po430/p0505 1st two plugs towards front of motor are black last two to rite look fine. runs great when plugs are clean .when two left plugs get dirty/fouled car wont start unless you give /pump lots of gass/clean plugs starts great/runs great.then starts all over again about every 500 miles.clean plugs beceause have bought to many.need to fix problem.
Submitted: 5 years ago.
Category: Nissan
Expert:  rpmdiag replied 5 years ago.

rpmdiag :

Hi, I'm Ron and I can help you. It looks like the cats are bad or the O2's are reading wrong. This problem needs to be corrected first. Make certain the O2'sare working right, don'y worry about the cats yet, we need to get this in fuel control first. If the O2's are good, then weneed to lookfor leaky fuel injectors in those cylinders. See attachment of how a good O2 should look in each segment. Hope this helps, Ron

Full Size Image