Well... 41 is O2 sensor, not to bad to change; however I don't know anything about the EVAP. I have removed all smog items(not sure if it matters) and have all new EGR stuff so that code is gone. How to fix the EVAP? New, junkyard, or heck with it?

 

Code 41 means the O2 sensor was stuck low for an extended period of time, or in other words it's reading a lean condition all the time. It could be the O2 sensor is lying and it needs to be replaced. Or it may be working and you really do have a lean condition.

Code 34 is a EGR code.

 

Would the egr cause it to run lean? Its had the code since i first bought it. i put a new egr and new sensor. Reconnected broken vac lines. New plugs, wirers, cap rotor, coil, control mod, new timing chain, removed smog system, new filter, pump, relay, Ive been having issues with it staling and backfiring after running 30 min or so. It smells rich. Waiting on a time light i ordered so i can run a full line of diagnostics. I havnt worked on a truck for 20 years; however, "I" would like to be the one to figure it out... with a litte help(and advice)

 

If it smells rich, then the O2 sensor may be lying, and the computer is making the engine run rich to try and satisfy what the O2 sensor is telling it. I supposed the easiest thing to do would be to change the O2 and see what happens.

On the code 34, the guy in the book says to read the codes, KOEO (Key On, Engine Off). You will get two sets of codes in the KOEO test, the first set is actual faults the computer sees at that time, and the second set are the memory codes, codes that the computer has stored from previous runs. He says if you get a code 34 during the first set of codes in the KOEO test, that it means you have a problem with the EGR sensor on top of the EGR, a problem with the wire to the sensor, or a piece of dirt or something in the EGR and it's holding the EGR valve open all the time. He said the code 34 is generated because the computer is receiving more than .67 volts from the sensor on the EGR valve.

The above is only for codes received during the KOEO test. There are different things to look at if the code 34 is only received during the KOER test (Key On Engine Running).

 

Yea, I think I read the same book. If I read correctly I need to do 4 tests. Key off, key on, timing test, running. If it ever stops raining here ill do the first two, then wait for my timing light to come in the mail. My old one crapped out. Thanks for the help.

 

After changing out coil and rebuilding dist. no more cutting out and backfiring.
Ran a KOEO test after a 30 min test drive. Showed a code 11. I did the fat man happy dance, till the CM test showed an 18.
That's a new one for this truck. O2 sensor came in today. Should I go ahead and install it or wait for the timing test and KOER. Then I read there are 3 other test I can run after that.

 

Yes, install the O2 since you don't know the condition of the old one.

 

might be this week end. Timing light came in, but Ive been to busy to get to it. I have been driving it every day. No major issues.

 

Code 18 is a problem with the pulses from the distributor, not the O2 sensor. Did you put the spout connector back in place after timing it? If you forgot it, that will cause a code 18.

 

Havnt timed it yet. Maybe tomorrow.

 

Well crap! I can't find the spout any where. It had a lot of cut wires and "jerry rigged" repairs in that area. I spent a day cleaning it all up. Do I need to go to the bone yard and find one? I'm going to try and time it without it for now. O2 sensor will have to wait till tomorrow.

 

This looks like the area that it should go.

 

The wire you are looking for will be yellow with lightgreen dots. That might be it in the picture, the lightgreen dots may have darkened from age and the heat of the engine. The spout connector is c170 in the diagram on page 60 in this link.

Electronic Engine Control - ???Gary's Garagemahal

That large white dotted thing around the wires in the diagram is a tin foil shield, there are small signals on these wires going to and from the computer and the distributor, the spark plug wires can interfere with these signals. So if you re-did the harness, make sure the foil is still there. I have taken sticky aluminum tape they sell in the store in the body work section and wrapped it with that to repair it, along with some bare wire.

If those are the correct wires, all you have to do is separate them like they are to time the engine, and then just take a small wire nut and twist them together to make it run and get rid of the code 18. What you are doing is taking timing control away from the computer so you can time it with the light. Then when you are done, you re-connect the wires so the computer now has control and can advance and retard the timing of the engine.

 

Thanks. I put a spout in and it's working correctly, got rid of the 18 code. O an C tests are clear, not so much for the R test. It popped 4 codes. 41, 34, 13 and 77. 77 and 13 I find odd cause it revved itself and never asked (98) for me to do it. I tested it twice. I'll clear comp when I install O2. (30min no battery?) I am yet to pop in the O2. Didn't think timing would take so long. It ran better before I put the correct timing on it. Hope the O2 will balance it back out. I'll put the shielding back on it. I was wonder what the heck it was for.

I didn't see the black and purple on the diagram?

 

There is a darkgreen/purple that goes to the oxygen sensor. Maybe that is not black, but darkgreen? That would explain the code 41, oxygen sensor is low all the time.

Code 34 is a EGR fault code. I drive with that code all the time. I would not worry about it.

Code 13 means you have the idle stop screw turned in too far, so it can't control the idle properly. I would not worry about this one unless you are having high idle rpms, in which case you need to turn that screw back some. If you unplug the IAC when the engine is idling, the idle speed should slow way down. If it doesn't that is what is causing this code. But, I have to run my ranger idle screw in too much to make it run correctly. I have spent years messing with this thing and still haven't figured out what is causing the rough idle, but raising the idle speed up makes it go away on mine.

Code 77 is because you did not rev the engine when it told you to. During the running test after the codes are spit out it will sit there for a little bit, and then there will be one blip that comes from the computer. When it does this you are supposed to floor the gas pedal and let the engine rev up past 2000 rpm. If it doesn't get past 2000 rpm, it will set this code.