If he needs to swap the injector wires, then he could tie in the O2 sensor wire into just the right bank and plug the bung off.

All we need to do is cover the bases.

 

Something else I need to mention. After I got my firing order straightened out, and finally got the timing set correctly, as I mentioned earlier, the engine was idling great. I let it idle for at least half an hour. Then as I was walking around looking and checking things out, I happened to see that I had forgotten to put the PCV valve in the grommet. So, I actually timed it with a major vacuum leak. I inserted the PCV valve and checked my timing. It was still on 10*BTC, so I didn't do anything else to it. Could this be the cause of my current situation? Is there a way of resetting things besides unplugging the SPOUT? Maybe disconnecting the battery? It's just strikes me as strange, that it was idling great from the beginning, for as long as it did. If an injector or the IAC was the cause of this problem, would it not have been having these symptoms upon initial startup?

 

If this truck has dual upstream sensors that is correct advice but if it only has a single upstream sensor by design or through modifications as timbersteel suggested then swapping injectors pins is not a problem.

 

I stand corrected. Good to know for future reference.

Did you get a chance to pull codes yet?

 

Make sure all the vacuum leaks are taken care of, then try disconnecting the battery for a few minutes to reset the computer.

 

Just checked codes. Lots of codes. 116, 121, 157,158, 172, 173, 334. 334 is the one that I suspect is causing the erratic idle. EGR Valve Position Sensor Closed Valve Voltage Higher Than Expected. I tested the circuit in accordance to the repair manual. It is getting the correct voltage from the PCM. Wasn't able to check the other circuit. I couldn't find my vacuum pump. One of the terminals in the EGR connector was corroded. I cleaned it and re-connected it. 172 and 173, I haven't tested the O2 circuit yet, but I suspect that the O2 sensor is bad. 157 and 158. Don't know how to check the MAF connector, or what the voltage should be. My repair manual doesn't even list those 2 codes. 116 ECT higher or lower than expected, and 121 Closed Throttle Voltage Higher Or Lower Than Expected and 121 Indicates Throttle Position Voltage Inconsistent With Mass Air Flow Sensor. I'll explain that code in another post. I know the cause of that one. After the repair to the EGR connector, I chose to clear the codes I want to tackle one item as a time. After start up I checked timing again. It is where it was supposed to be. I let it idle for about half an hour. It idled great. I'll check codes again in the morning and let it run some more.

 

Now as for code 121. 2 years ago when I first got this truck, I was driving it one morning. All at once, it wouldn't take throttle, and when I pulled off to the side of the road it idle real low and died. When I started it back up, the idle would not pick up, and while I was checking things out, I noticed that if I held the throttle up off the bottom, it would throttle back up. So, not knowing anything about these engines, I adjusted the throttle screw. So now, it sets off this trouble code. Come to find out my TPS was bad. I replaced it, and then I started a thread about how to adjust the idle screw on the throttle body (this is still 2 years ago). Someone explained to me, how to adjust it. So I adjusted it, put on the new TPS, and it drove and idled fine, as it is idling fine now. Another thing I did that was a no no, was, put it in a can of chem dip. The sticker was gone off of the throttle body, that is why I didn't know about the idle screw and the chemicals to the inside of the throttle body. I also threw my IAC into the chem dip. Everything got left soaking over night. The IAC doesn't seem to be effected. I did the resistance test on it yesterday and it tested fine. So, now I guess I need to replace the throttle body. My research last night, showed that a throttle body from 94-96 will work. When I install the new used throttle body, is it as simple as, clearing the codes by disconnecting the battery, for the computer to accept and correct the throttle position?

 

I would address the other codes before replacing the throttle body. If you got the ECT code with the engine fully warm, you should replace the ECT sensor or make sure it's plugged in properly. The O2 sensor should also be addressed.

 

Is the ECT sensor the single wire sensor that screws directly into the left front of the intake manifold, or is it the one that screws into the tree on the right front of the manifold? I replaced the one in the tree with a new one. If that is the one, I'll unplug it and see if there is any corrosion on the terminals. I ordered a new one because, when I removed it from my old engine, the plastic part was loose. I ordered it off of Ebay. I didn't know what it was called. I ordered it by the part number that was on it.I know some sensors are color coded, and you have to order the correct color, but I did not find any information like that on this particular sensor. But, I believe the old one was black, and this new one is grey. But it is the same part number. Do you know if there is a difference in the colors? Is it possible there could have been an air pocket there that could have caused a false reading? Maybe the computer picked it up while I was bleeding the coolant system.

 

I just got back on Ebay and seen that the grey one is a TX6T, and the black one is TX6.

 

I let the engine idle, last evening, for approximately 1/2 hour, after I cleared the codes. Everything seemed to operate as normal. Just a little while ago I started the truck up, to move it over a little, to give myself enough room to pull my rear axles so that I can change the seals. The engine was still idling smooth. So, I decided to check the codes. 121 and 334 has returned. 121: Closed Throttle Voltage Higher Or Lower Than Expected and 334: EGR Valve Position Sensor Closed Valve Voltage Higher Than Expected. Since the engine is still idling smooth, I guess I can rule those two out, as to the cause of the rough idle I was having. The O2 sensor wouldn't cause it to do what it was doing, and I don't believe the ECT would either. So, that rules out codes 116, 172, and 173. All that leaves is codes 157 and 158. Both of which have to do with the MAF. I wonder if the MAF would cause the rough idle? Or if the PCV valve that I left unplugged could have possibly triggered the MAF symptoms. The rough idle condition that I had yesterday, happened after I inserted the PCV, NOT while it was out. So, now I guess I just have to wait to see if the condition happens again, and if it does, recheck the codes and see which one is new.

 

It can. I saw a 94 f150 die and barely run after restarting because the intake tube pulled free of the MAF because the motor mounts were so bad the engine torqued enough to yank it free. It was hooked up but no airflow being read so it was all wacked. Perhaps you have a bad connection or bad wire. Something to ponder.

 

You need to adjust your TPS voltage so it sits below 1.1 (preferably under 1.0) volts at idle, then address the EGR code. If your EGR is leaking, it will cause all kinds of mixture issues as well.

 

How do you adjust the TPS voltage?

 

Well officially the TPS is non adjustable, as the computer will accept anything between ~0.6v-1.1v as a valid idle reading. If your TPS voltage is too high for idling, it likely means your idle stop screw is adjusted out too far.