slcpunk74

I just bought this 94 yoda prerunner with the 3.0(I know) 5spd 4x4 yata yata

anywho it has been burning oil and smoking on startup here and there but just recently the check engine light would come on and it runs a bit off in the lower rpms and wont smooth out till about 2500. I did the self diagnose and it came up with a code 25...

I just changed the plugs and they had a little oil on them(obvious) and they also looked rich. I was reading up on what the code 25
AIR/FUEL RATIO LEAN INDICATOR--LEAN SIGNAL SENT TO ECU FROM O2 SENSOR
--INJECTOR FAULT(S)

--FUEL PRESSURE

--OXYGEN SENSOR

--AIRFLOW METER OR MAP SENSOR

--IGNITION

--ECU

so the only thing I can think of is that maybe this oil I am burning is making my o2 senor hate life and that is why it is rich..?

I am sure you guys have many good thoughts on this thanks

turyota90

check your maf. can make for a lot of problems if bad

slcpunk74

how do I check maf?

I forgot to mention but when I reset the computer it runs good for a while till the light comes back on

BoostinChick

Check up on my thread...lots of good info there if your truck is doing the same thing mine is:
https://www.yotatech.com/forums/f116...k-gear-150667/

abecedarian

code 25 is air-fuel ratio lean (not rich)
possible causes:
engine ground bolt loose
E1 circuit open
injector circuit / injector
fuel pressure low
VAF meter malfunction
PAIR system malfunction
Heated O2 sensor heater circuit malfunction
O2 sensor malfunction
Ignition system (timing, etc.)
ECM (ECU) malfunction

BoostinChick

You must have this bookmarked somewhere for n00bs like me :bats eyes:

turyota90

you can try unplugging the maf and see if it still runs or runs better. when they go bad they can cause the vehicle to run way too lean or too rich. make sure the intake tube isn't broken after the maf

slcpunk74

I do understand that the code says it would be lean but I also stated that to the contrary the plugs looked rich... That is why I was confused.

slcpunk74

I will give this a try and no the intake is not broken.

just a 22re

if the o2 is telling the ecu im lean the ecu will over inrich the motor to make the o2 happy but if the o2 is stuck on lean then its just going to get richer and richer get my drift

if you wanna check out the o2 get a multimeter its going to be your friend start your rig get it wormed up unplug the o2 with motor running and test it make sure you do it to spec like they tel you in the fsm if she goes low in volts to high in volts you know the o2 is fine if it stays low or high then you know the o2 dumbed out on ya

hope it helps in my rig i have a air/fuel gauge on the piller so i can gheck on the fly and i know if thers something wrong

just a 22re

oh and by the way nice location you got there buddy lol