so i have a problem. the truck would stall when shifting to park.
cleaned the IAC and the throttle body.
doesnt try to stall anymore when put in park but i knew the IAC wasnt working right
so i replaced it with a brand new one.


but now it is running pig rich !
engine smell fuel like i had the nose on a gas tank...
there is a small white smoke ONLY when i release the gas pedal.
the white smoke smell fuel too.
sometime engine try to stall and if it stall it is really hard to start again.
all i can do to start it is gas pedal to the floor untill it start then pump it 3-5 time.
also the truck has no power it feels like im in a civic.
i can smell fuel inside the cab when try to see if he has power.

battery = OK ( pass volt test , load test , charge test )
fuses = OK
fuel pump = very loud when engine running but some ppl say it's normal.. so OK i guess
obd2 scan = OK
before my cluster die , all gauge indicated normal value.
all sensor voltage around engine = OK
spark plug = brand new
plug wire = OK
cap and rotor = OK


this truck is like windows update. update to fix a bug , then 10 new bugs appear.
fix a problem , 10 new problem appear...


now i'm lost i really don't know what to do/check to fix it

 

I once had a truck that did that. a simple thing, although it will give you a code....is to unplug the precat O2. It would still run rich but the smell of fuel would be reduced. Don't forget to change your oil when you find out what it is. From the fuel smell your talking about it's contaminated. Not sure about the white smoke though, usually gas is black?

 

already tried that. change nothing at all.
those sensors are not used when the engine is cold ( open loop ), and the problem seems to happen more when it's cold ( but not only when cold )

nice try tho and thanks for trying to help

 

Almost sounds to me like you might have a hanging fuel injector or a dead hole. What are the short term and long term fuel trims looking like? Average fuel mileage? What do the spark plugs look like immediately after the issue? How are the plug wires/rotor/cap/coil?

Does it run hot or had any other cooling system issues?

 

plugs are black and very wet.
no temp issue

for fuel trim i can't check. i have 2 scanner and access to a professional one and none can get freeze frame without a MIL.

fuel mileage i dont know exactly but really thirsty. the truck didnt see the road enought yet.

what do you mean dead hole ?

what i dont understand is that before i change the IAC and clean the TB , yes it was stalling when put in park but i could burn those 235/75R15 in the rear. and now i have NO power at all. i bet i couldnt even spin a 175/60R15 lol.

 

you are losing spark. If all the plugs are wet, it's not the plugs or plug wires. double check the rotor and cap, the coil wire, and the coil itself.

 

well ive been able to do some test this morning...
still same trouble..
but almost each time i put a scanner on it it throw different code.
ive enver had a code about transmission sensor since i changed both.. and BIM this morning it throw a code i had before changing them.
the truck is stuck in 2nd as before.

and also now a new code about 02 sensor...
and a IAC code...
weird they are ALL about HIGH voltage...

i checked the IAC and reading are fine ( komhs and volt )

i think my problem is the PCM or a bad ground...

can i test the PCM ? if so how i do ?

 

problem fixed. the new IAC was the wrong one ( smaller tip ). bad listing i guess.
got one from a u pull junkyard and work fine.
another problem but ill create a new thread for that.