1993 ford ranger xlt 4.0 v6 4x4

[JS116]

Hello I am new to the forum. I look at threads all the time on here trying figure out things on my Ranger. Has been very helpful. Now I but my Ranger several years ago after destroying my wife’s 94 ranger from when she was in college. A guy ran a stop sign and t-bones him. It was a great truck so we decided to buy another one close to the same year because it was a good truck. Weeeell…we bought a 93 and it has been nothing but a pain in my but since I have had it. I have practically rebuilt the truck it seem like. New engine and it still doesn’t run worth a crap. The mechanic I used decided to not put the o2 sensors in the exhaust pipes. I was under there changing radius arm bushings and noticed the o2 were zip tied to the fire wall! And the hole were plugged with old o2 with the wires clipped off. So I decided to to installed new o2 and put back in the exhaust, well that was a mistake. The truck skipped like it was running on three spark plugs. So decided to disconnect them. It runs really good when the temp outside is above 55°F but if it is below look out runs like crap. I have had several mechanic look at it and try to fix the issue but no one has been able to fix the issue. Now the check engine light comes on and stays on all the time. Have disconnect battery to reset computer and have have gotten the codes it is throwing but have no clue what to do with them. This thing has collared me to death. Anyone want to attempt to help me out?

 

[RonD]

Welcome to TRS

Post the codes

Common issue in 20+ year old OBD1 computer is failed capacitors, 3 of them, under $5 to replace
Pull out the computer and open it up

1993 4.0l will have two O2 sensors, one on the right(passenger side) and one on the left(drivers side), they HAVE TO be put back in on the correct side or engine will run like crap
But there are 4 wires and only 1 wire color difference between the two connectors
Red/black wire is for Drivers side O2
Grey/blue wire is for Passenger side O2

So make sure that is how they are hooked up when you hook them back up

 

[JS116]

172, 176, 121 and 522…the last two I figured out what was wrong.lol

 

[Josh B]

My check engine light burned out years ago, I sure miss that thing Welcome to TRS man

 

[JS116]

My check engine light burned out years ago, I sure miss that thing Welcome to TRS man

That’s an easy fix but it may open a new can of worms.

 

[JS116]

Welcome to TRS

Post the codes

Common issue in 20+ year old OBD1 computer is failed capacitors, 3 of them, under $5 to replace
Pull out the computer and open it up

1993 4.0l will have two O2 sensors, one on the right(passenger side) and one on the left(drivers side), they HAVE TO be put back in on the correct side or engine will run like crap
But there are 4 wires and only 1 wire color difference between the two connectors
Red/black wire is for Drivers side O2
Grey/blue wire is for Passenger side O2

So make sure that is how they are hooked up when you hook them back up

Hey the truck runs better with the upstream O2 sensors out than they do in. I connected them back up but didn’t put back it the exhaust pipes. Still has a lean code those even if I unhook battery for 10min and reconnect it will come back on in about two miles. I have also notice in I turn the truck off and crank it the light will be off but come back on again in about 2 miles or so. Is there a way to check for a vacuum leak without a smoker. Is there a trick? I read somewhere that you can disconnect the IAC plug and if the if the idle drops to 500 rpms then there isn’t a vacuum leak. Is that true? Should I plug the sensors back in upstream? It has been running like crap with the sensors in. Will blow the engine or hurt it to run with the sensors out?