hmongyota

yes... i am new here.. thanks to this forum it had helped me fixed minor problems... but now with this CEL 25... ive searched on this forum and on other forum site but cannot seem to help my truck problems at all.. and yes i've used the SEARCH already... "many times" to where i had to make this new post...


okay.. i am seriously giving up on this truck.. i love it but if i cannot fix this issue... it is probably gonna go to a dumpster..

i have a 94 sr5 3vze.... 180k mileages...

here is the problem...
the truck runs really rough and sluggish... hella slow acceleration... when i start the car, it'll have a strong bad smell of gasoline... while warming up my truck, the tail pipe will have water dripping out.. but the water dripping out is actually mixed with unburnt fuel too... black and dark.. also, when i rev the engine, right when it drops to about 1k rpm.. i can hear a loud pop (backfires).. i do see black smoke coming out when i rev the engine... then last week, i noticed that driving it, the cat glows bright red... like a cherry.. i am guessing that too much fuel are being dumped into the cat and it is not getting combust in the chamber... i am getting bad bad gas mileage.. on a full tank of gas.. i get about only 100miles only.. that is bad!

things i replaced/or done to try and help the problem but no luck!
-ive switched out the AFM with good ones.. but code 25 still comes back
-replaced the Fuel pressure regulator
-replaced the water temperature sensor (this actually fixed my Overdrive problem instead of Code 25)
-replaced cap & rotor, with new spark plugs and new wire plugs
-ive checked for any vaccum leaks but didn't find any...
-replaced the Throttle Position Sensor (still needs to adjust)

so yes.. i understand i need to adjust the TPS.. so do we have to take off the manifold to adjust the TPS or can we adjust the TPS while the manifold is still on the engine?

please clarify.. i am seriously going nuts! LOL

Levinz11

Code 25 is your O2 sensor. Have you checked that out. All trouble codes are here: http://www.ncttora.com/fsm/1990-1995...e/diagnosi.pdf

rustyf99

iTrader: (1)

There's a large dumpster in my driveway, you just leave your Runner here.... :-)

Seriously you are running way rich, have you cleaned the injectors? Is there gas in your oil? It's odd to get a lean code with that rich mix, def. check your 02, it's probably toast. The injectors could be dripping fuel into cyls when engine is off creating super rich condition on startup - and burning up your 02, worsening the problem by throwing a lean code which richens the mix more.

hmongyota

BUMP!

well i uran a bottle of stp into my tank.. but it didnt help anything... what do you think is causing it to run rich and giving code 25 at the same time? i am like hella lost.. i havent taken out the injectors and take a look at them yet... what should i be looking for? as for gasoline in my motor oil.. i dont think theres any in there... the motor oil still looks good.. im guessing my headgasket is still good.. because im not loosing any coolant either...

any other advice or what i should be looking for?

i wont have the time today.. but when i get off work tomorow.. ill try to take a look at whatever advice you guys give me...

thanks!

rustyf99

iTrader: (1)

Start by getting your tps adjusted, you can do it on the truck but its easier to pull the throttle body off and do it on the bench. Then check your o2 sensor - you need a multimeter, the FSM has instructions for all of this. Links to download the Fsm are on here - just search quick.

alltracman78

Adjust your TPS first. Not because it's the problem, but because you should ALWAYS start by fixing known problems. It helps to set everything else straight.

The code 25 is probably causing it to run rich. Code 25 means the ECU is getting a very lean signal from the O2 sensor [low voltage, above .45V is rich, below .45V is lean, the further you go from .45V in either direction the more extreme the signal]. Because the signal is too lean, the ECU is adding more fuel to try to compensate, only it still sees the lean signal, so it sets that code [and keeps adding fuel].
This is probably caused by;
-bad O2 sensor [you will see a very low signal, ~ .2V]
-air leak in the exhaust somewhere before or at the O2 [not as likely, the exhaust is slightly pressurized so it's harder {but not impossible} for outside air to get in]
-bad O2 signal [the wire/connectors have corrosion or damage, lowering the signal that is actually reaching the ECU].

It is also possible you have a misfire in 1 or more cylinders. Because the mix isn't completely igniting the O2 sensor sees the extra [unburned] oxygen and sends a lean signal to the ECU, while the unburned gas comes out the exhaust.

hmongyota

oh yeah.. to add to that.. i do recalled when i changed out my spark plugs... i found that one of the spark plug had motor oil on it.. i know that, that is bad.. i forgot which cylinder it is.. but do you think that can be part of the issues?

hmongyota

Okay... i figured out the problem.... i hate leaving thread unfinished... so ima finish this thread...

So my problem was that i had about 2 of my spark plug wires sorta got burned touching the exhaust tube to the EGR vavle... after finding thr problem.. i just taped up the spark plug wires with electrical tape and ziptied it to a secured location and now the code is gone and no more gloeing red cat....


Couple other problems did come up but im not too worried.. i woild need to replace my cat soon because it was basicallu melted during the time i couldnt find the problems... i still need to adjust my TPS and maybe my IACV needs to be replace...


Tada! So hopefully this help someone who is or was in the same state as me...