Fine tuning on a budget

[dssranger]

I recently replaced the FI's on my 2.9L 1986 Ranger, It started right up, but I noticed it still had a fast and sometimes loping idle, run fine at higher RPM's I thought I would just replace all the emission parts..until I looked at the cost of about $400. for everything. So I have decide to go bit by bit to solve the issue. I replace the Air Charge Temp sensor, the resistor wire in it was completely fried, I adjusted the TPS, it was running at 1.59 V at closed idle I adj it down to 0.95V this was when it was cold, started it, ran and idled great. After it warmed up it started to sputter and died, it would not restart without pressing the accelerator, readjusted the TPS to 1.03 V and it idled okay, I have not had a chance to let it sit to be cold started and see if it will stall again. The TPS adj through the throttle position to full open at 4.70V I am going to remove the IAC and see if it is damaged like the ACT was and clean it. Does any of these symptoms point to anything else more specific?
Thanks for any suggestions

 

[IMenriched]

I recently replaced the FI's on my 2.9L 1986 Ranger, It started right up, but I noticed it still had a fast and sometimes loping idle, run fine at higher RPM's I thought I would just replace all the emission parts..until I looked at the cost of about $400. for everything. So I have decide to go bit by bit to solve the issue. I replace the Air Charge Temp sensor, the resistor wire in it was completely fried, I adjusted the TPS, it was running at 1.59 V at closed idle I adj it down to 0.95V this was when it was cold, started it, ran and idled great. After it warmed up it started to sputter and died, it would not restart without pressing the accelerator, readjusted the TPS to 1.03 V and it idled okay, I have not had a chance to let it sit to be cold started and see if it will stall again. The TPS adj through the throttle position to full open at 4.70V I am going to remove the IAC and see if it is damaged like the ACT was and clean it. Does any of these symptoms point to anything else more specific?
Thanks for any suggestions

For saving costs on items , best to start with getting codes. It can be several things yet. can't stress enough the importance of good grounds and connections for relatively simple thing to do.

you're correct with the adjusting the TPS to the .95v....it maybe though that your TPS has dead spots , maybe. Did you use a needle sweep multi-meter (aka analog), or digital? the needle will show dead spot better visually....movement should be smooth and proportional to actuation of the TPS....any jerky or hesitations in the needle movement...hints of the dead spot. this is telling you that the TPS is done or nearly so.

 

[RustedRanger]

Did you "blank" out the computer by unhooking the battery after working on it? It can't adjust for improvments. Once I put Restore in the oil and Lucas treatment in the gas and it ran worse.....until I cleared the computer out.

 

[dssranger]

Update

Actually the battery went or was bad, I charged it and I had to replace it, that is why I am on a budget with it. I cleaned out the IAC and replaced the the gasket, started it and it did the same thing, next day I unplugged the IAC before starting it, it would not start; plugged it in, started and it ran better, did not stall after reaching operating temp has been running since. I realized today that I am hearing a whining from underneath the truck, crawled under the fuel tank, the fuel pump is definitely making a noise. I am going to have to replace the fuel pump(s), both the high and low pressure, so much for a budget fix. I have twin tanks also, I think I may have three pumps. But the noise is coming from the front tank, so I will replace that one and the high pressure one on the rail.