screamer76

where to start? i have a 95 3.0 5spd 4wd non-cali 4runner with(according to the odometer) 106,000. i failed emissions yesterday with slightly high hc

in the drive portion of the test. the cat and egr modulator were replaced right before i bought it in july of 06(93,000 at the time)and it passed

emissions the day i got it. i had code 71 almost immediately after buying it, and found that all of the metal vacuum rails for the egr system were

corroded so badly on the inside that they were totally obstructed. i bypassed them with new longer rubber vacuum lines and cleaned out the ports on

the throttle body and vsv and code 71 went away. i'm pretty sure they replaced the modulator for nothing. soon after that i recieved code 25. i have

replaced every vacuum line except the 4wd and power steering and some of the larger odd sized ones and i'm fairly certain none of those are leaking. i

tested the fuel pressure(had to buy the fuel pressure tester and a multimeter and a vacuum pump and i can't remember wtf else to do all of this stuff,

but it seemed like a better investment than the EIGHTY DOLLARS AN HOUR that the shop by my work wanted for diagnostic. i can't afford ten an hour

with the screeching halt in the housing industry) which came up too high, and replaced the fuel pressure regulator. fuel pressure seemed right in the

second i had to look before my stupid actron tester started spraying gas everywhere from the dial. what had been a high idle then became a low idle

with stalling soon after cold engine starting. actually on cold engine starting the idle would raise and lower from about 500 to around 850 then slowly

that would taper off to a steady 5 or 6. it did the fluctuating idle thing before the regulator was replaced, but it went from 800 to 1200 and would

eventually sit around 12. i adjusted the idle scew out as far it would go with no signifigant change and felt that i had to adjust the throttle cable to

temporarily compensate. hopefully that wasn't a huge mistake, but i'm new to efi and didn't know what else to do. spark plugs have been changed

twice now and show supporting evidence of the lean malfunction. coil seems good. distributor has proper resistance. the wires and cap were also

replaced when i got it so they are about a year and a half old now. i hooked up an inductive timing light to each wire, including the coil and verified

spark. i tested the air flow meter for resistance and it seems to also be okay. i replaced the water temp sensor because i broke the old one trying to

remove it for testing. i tested each individual injector, the cold start time switch and injector, and the o2 sensor all for resistance, nothing. i haven't

seen any suspect wires or connections to any of these parts. yesterday after failing i tried to have the injectors flushed and that doesn't seem to

have changed anything. lately i've noticed that i can actually hear over the running engine air coming out of the filter for the pair system vsv. is it

possible that too much air is coming out of the filter? it seems really loud considering that i never notice it from the other vsv's surrounding it. i saw in

my factory manual that the pair system partially controls hc content. is it possible to switch that vsv with one of the ones from my 4wd with the

same electrical connector for the purpose of diagnosing it? it certainly looks the same but wtf do i know? any advice from someone who knows their

s%#t would be so very greatly appreciated. i have six weeks until my tags go bad, and no money for error.

Targetnut

code 25 fuel system lean is triggered when the O2 sensor output voltage remains to low even after correction by the ECM this can be caused by air leaks any where in the intake tract low fuel pressure dirty injectors misfires caused by secondary ignition components malfunctioning sensors coolant temp sensor, airflow sensor this also includes the O2 sensor. It is not uncommon for a failing O2 sensor to trip a code 25

And please,

use punctuation and break up your post so that it is not so hard to read

like this:

code 25, fuel system lean is triggered when the O2 sensor output voltage remains to low even after correction by the ECM.

this can be caused by air leaks any where in the intake tract.

low fuel pressure.

dirty injectors.

misfires caused by secondary ignition components

malfunctioning sensors coolant temp sensor, airflow sensor

this also includes the O2 sensor. It is not uncommon for a failing O2 sensor to trip a code 25

screamer76

Ok. Sry about that. Still new to this. Maybe i'll try just buying a new oxygen

sensor, but first i'd like to try swapping my pair vsv for one of the ones for my

fwd. They have the same type of connection and the vacuum lines and filter

are in the same locations. I'm just nervous about doing it. Does anyone know

the vsv's that i'm referring to?