I have an '86 ranger with a newer '92 2.9 v-6 with automatic. The original engine locked up, so I replaced it with the '92 2.9, also, this truck had been sitting for about 3-4 years. Mice have chewed a few wires, and as far as I've been able to find, I think I have repaired all of their damage. The replacement engine seemed to run fine when it was pulled, but since putting it in the '86, I've been pulling my hair trying to get it to run right. It idles rough and has no power.

The KOEO trouble codes I was able to pull were: 89 (On-Demand Service Code) and 22 (Continuous Code). Chilton tells me the 89 code is from an Exhaust Heat Control Circuit Fault & could be caused by Exhaust Heat Control Solenoid, wire harness problems or ECA problems.

The 22 Code indicates a Gross MAP/BP Sensor Signal Error occurred during recent operation. Possible causes are MAP/BP sensor problems, wire harness or ECA problems.

Since I can't find an Exhaust Heat Control Circuit, Exhaust Heat Control Solenoid, or a MAP/BP Sensor, am I mainly looking at wiring or ECA problems (I know, most likely). Does an '86 Ranger even have any of the above mentioned items? Is the Exhaust heat control refer to the O2 sensor? I've found reference to the MAF sensor, but haven't been able to find anything as to where the MAP sensor would be.

Any help appreciated - thanks

 

I haven't seen Chiltons 2 digit code list, but my code lists state that an '89 is a TCC overide solenoid fault. The TCC solenoid controls torque converter clutch (TCC) lockup. Are you using the '92 or the '86 computer? I expect this code is a missed wire in installing the '92 engine between the PCM and the transmission. If you're using the '92 computer, there will be an extra wire at the PCM that doesn't have a matching wire at the transmission. That's because the '92 A4LD uses two solenoids (one for 3-4 shift control and one for TCC lockup control) but the '86 A4LD only uses one (for the TCC lockup control).
Before dealing with the CM 22, run the KEOR test.

 

Couldn't find any problems with the wiring leading to the transmission, and everything seemed plugged in. I used the '86 computer, so I guess the TCC could be bad. But, I ran the KOER test 3 times, and came up with a BUNCH of codes. The codes that came up each time were 12, 13, 16, & 25. 1st test gave: 12,13,16,22,25,77. 2nd test gave: 12,13,16,25. 3rd test gave 12,13,16,21,25,64. I did mess up the timing on the "goose" test I realized later, so that could account for 1 or 2 errors possibly.

But, it seems that the common denominator seems to be the computer, which I have no idea if it was good when I began the engine switch since I bought it not running. Am I thinking correctly and if so, what's a good price, or good place to look for one?

thanks

 

The EEC-IV computer doesn't have the ability to detect a bad torque converter clutch. It can only see an open or grounded TCC control circuit. In any case, this code probably has nothing to do with the way your engine is running, unless something has been hooked up wrong.
I haven't ever dealt with the 12, 13, or 16 codes. I get the feeling they are often more symptomatic than diagnostic. Whatever causes the engine to run bad makes it run bad enough so that the computer doesn't feel good about the KEOR test because the engine RPM wasn't stable.
Only time I've seen a 25 was when I didn't give the throttle a good, assertive 3/4 to full throttle "goose" for the goose test. However, as it relates to your situation, not all 2.9's had a knock sensor. My experience is with an '87 which does have a knock sensor. Starting in '88, they took off the knock sensor (and EGR system), and I don't know if they put them back in by '92. Did the '92 block have a place for a knock sensor? BTW 77 is usually a result of not getting any kind of goose for the goose test.
It could be a problem inside the computer, but the computer's don't go bad that often. I'd try a few more diagnostics. Things like timing (make sure to check with the SPOUT unplugged) and fuel pressure. Make sure the spark plug wires are hooked up right.