93 pathy wont start

[aitken1929]

hi im new to this forum, pathfinder and 4wding, so im not entirely sure about some of the componets.

The problem i am having is that the truck wont start i recently replaced the MAF sensor because code 12 was showing, but when my dad went to clear the codes but i think he has done something with one of the other modes and now it wont start...

i have eliminated spark that is working, and fuel delivery is there as well.

the only thing i can think of is the ecu??? is there anything im missing???

[aitken1929]

ok i got her running the plugs were black, but idle is really bad and running really rich. the idle levels out when you unplug the maf sensor then goes back to crap when i re connect it.

am i going to need to get another maf sensor? or is there something else i should check.

[mar1]

sorry bro cant really help you, but this post is to assure you that.. YES there is someone reading.

hope you get a reply soon

[hfrez]

Sorry buddy, you seem to be doing the right things and maybe the MAF sensor is your problem. Can not tell you for sure though.

[faceless]

we have this issue on the motorcycles we work on. try checking your vacuum lines. if one has a slip it will mess up. also check the wires and make sure they aren't broke. just and idea

[aitken1929]

thanks for the replies guys, glad there is someone reading

problem still not solved but i did find half of a broken bottle brush in some of the vacum lines which wouldn't help matters... i have checked the vac lines for cracks ect also sprayed them with carby cleaner for changes in idle no good going to order a new MAF sensor, o2 sensor and temp sensor hopefully they will help matters. i was doing some reading (not pathy problems but same symptoms) apparently cleaning a ICV (idle control valve) might help, is there one on the pathy or something similar and where is it?

i have a haynes service manual, and cant seem to find any decent pictures and labels of where everything is.

thanks again for the replies

[aitken1929]

just a update... installed a coolant temp sensor, new maf sensor and new oxygen sensor same jazz, rough idle smoke out of the exhaust...

ordered a new pcv valve today there was hardly any suction so i figured it was nackered hopefully it works for the idle.

also noticed the oil was overfilled so maybe the could be contributing to the smoke??? going to change it tomorrow

any suggestions would be great running out of ideas

[Melbo]

Have you done a compression test --- I have an older V6 that runs way too rich but starts and runs so I use it --- Someday it will require a major overhaul but it only has 275,000 miles on it

[aitken1929]

Have you done a compression test --- I have an older V6 that runs way too rich but starts and runs so I use it --- Someday it will require a major overhaul but it only has 275,000 miles on it

yeh compression is fine,

taking it in to nissan monday to get a scan tool hooked up hopefully my ecu just needs to be reset or something

[aitken1929]

went to the mechanic today and they couldn't find anything either... might run new wiring to the MAF and see if that helps.

pulled the upper intake manifold off and placed a new gasket and sealant to stop any possible vac leaks that i could find, no good

i am running out of ideas

so far i have replaced the MAF sensor, Coolant temp sensor, oxygen sensor and pcv valve.
Checked and cleaned egr valve, vac lines, TPS connections, ICV connections, upper intake manifold.
Checked timing, compession and fuel pressure
ran some injector cleaner through
Left negative terminal off over night.

symptoms that still remain are rough idle, smokey exhaust seems to be missing while driving (it jutters)

[aitken1929]

i got sick of not being able to drive the truck so i went for a cruise to possibly see if the computer would reset its air flow values, so far the idle has levelled off but is really low prob about 200-300 rpms and take off is fairly jerky smoke has seemed to have gone but too early to tell.

just recently heard about seafoam?? is this any good? should i run it through the truck to get rid of some of the sootyness from the rich running?

[aitken1929]

just a update seemed to have fixed the idle and richness problem, bad earth on the maf, but when i take off it jutters a bit so i just have to work out what that is and then ill be set