CILO

Hi all, yesterday I got a cel code 25 on my 4runner (95,3.0,auto) prior to this i noticed that my idle had dropped to about 500 while in gear and i could feel some hesitation in the motor as well. I've done a search on this code and have come up with a mixed bag of possible causes, as you guys are aware. Anyhow, aside from the above symptoms, drivablility has not changed. I did pour a bottle of fuel injector cleaner a couple of tanks ago.
Here's a list of what i've replaced in the past year:

motor
spark plugs
wires
cap
rotor
fuel filter
tps

My guess is that the O2 sensor is finally on its way out but I'm not sure how I could test this, if at all possible.

Can anyone steer me in the right direction with this
Thanks

mr_lemons

i've had the same issue for like 9 months and I replaced all the same things... But I did notice I had cracks in the air hoses behind the air filter. I replaced that and I had a HUGE jump in power

CILO

i wonder if there's any way of inspecting the hoses besides visually. for example squirting the hoses with a spray bottle and check for any changes in engine speed

mr_lemons

Someone said spray with starter fluid, but I thought it was easier just to take them off and clean and inspect them

CILO

Ok back from outside, btw it is f@#kin cold out there, took apart the intake piping for inspection and low and behold there was a crack on the lip of the hose that connects to the throttle body. So as a temp. fix I wrapped the lip with a crapload of electrical tape to cover that crack. Reattached, cleared the cel and test drove it around the block. I did not get any light (still have to drive it a longer distance) and the hesitation has decreased significantly, although not fully. Hopefully that was the issue it was having. Although perhaps I should swap the O2 sensor as its outlived its useful life.

btw, thanks lemons

CILO

Well it appears the intake wasnt the issue. problem arose again the next day. went back out this past weekend and checked/replaced all my plugs, no oil or residue on cyl#6 (thank God) all my plugs were way off ( .037 to .042). this cured my slight stumble when gassing it right after starting. The engine runs well for a while and then the idle goes down to about 500 to 600 when stopped and in drive (automatic). so it seems the problem starts when the engine is fully warm.
Question: How hard would it be to test the fuel pressure and what tools are needed?

Also, would testing out the o2 sensor via the diagnostic port indicate if there's a problem with my o2sensor?