I have a 1995 ranger 4.0 4wd auto, and I
have no.1 some holes in my cats, no.2 a lean bank 1 code, and no.3 a high idle, it runs awesome in the cold besides the high idle, but when it gets warmer out. I dont know why but you have to 2 foot it sometimes or else it dies.... i took some pics, I unplugged the wiring on top of the throttle body and it ran the same, I also unplugged a wire in the middle of the intake tube and it ran just the same, any help?


The thing i unplugged while running, no difference made


This vaccum line was cut in half so i put a valve stem cap on It

I think the vaccum line plugs into this somehow, idk what this even is though.

 

Did the CEL(check engine light) come on when you unplugged the sensors, it should

Both sensor pictures are the TPS(throttle position sensor) 3 wire sensor, and no that wouldn't effect running warm or cold, might cause a hesitation when accelerating if unplugged

You need to find the vacuum hose for that open port and plug it as well, looks like EVAP solenoid or EVAP pressure sensor, does it have 2 or 3 wires?

Lean and Rich codes can be false unless you know the O2 sensors are under 12 years old
O2s are the ONLY sensors that have a time/mile limit, 12 years or 100k miles and they become un-trust worthy
But the high idle would indicate a vacuum leak which will cause Lean codes
Vacuum leaks are hard to find sometimes, but unhooked vacuum hoses are a good place to start

Is the CEL on when driving?
If so then get the codes and write them down

CEL should come on with key on, bulb test and tells you computer has powered up OK
CEL should go off when cranking engine over, means computer is getting a good timing signal from crank sensor so will start spark and then fuel injectors
CEL should stay off after startup if there are no trouble codes present

 

Hey thanks for the reply! The check engine has been on for the past month, though it's always idled high. And I don't think the 02 sensor has ever been replaced. Do you think the holes in the cats could be part of the problem?

 

Well, quick update, I went to my truck while it was running and unplugged the MAF sensor and immediately the rpms dropped to 500, then I plugged it back in and it still stayed at 500, drove it around the block and put it in park, still st 500, didn't even sputter out and die, is this good, or bad, and that evap system has 2 wires coming from it, thanks!

 

Sorry, I unplugged the IAC valve, not the MAF sensor...