I have a 1989 D150 5.2 EFI.I will start with what has been done new plugs,wires,cap,rotor button,coil and the throttle body was rebuilt about a year ago.The map,Throttle position,and idle speed control has all been replaced.The problems i am having is when i start her up the engine shutters and seems like it has a misfire.It will start up but runs rough.The codes that it shows is 43 which i already checked the hall effect (which is about a year old sense i replaced it.I checked the battery and it is putting out 13.48 at idle the coil is 12.8 at idle is this too high?I also have code 14 map sensor could my voltage regulator be going out?Thanks for any help......

 

Voltage are likely pretty close at idle. The code 14 would be what I would be looking at.

 

would that also cause the code 43 to show also?This all deals with voltage right too low or high for the computer to read.

 

I am showing code 43 as Ignition coil circuit..... PCM isn't seeing the voltage it wants from the coil. Have you check coil resistance?

 

Update.....I replaced the coil again with another new one the computer cleared the code 43 and i replaced the map sensor.New problems have occurred,I also replaced the voltage regulator with a new one (which i always keep 2 new ones laying around.I cleared the computer now it shows code 46 i have tried 2 new regulator and still the same thing ,I also have code 26 now the injectors this to all occur to be back to the voltage problem over charge,The truck has never acted like this before until this voltage problem happened.What about the computer could it be going bad and messing everything up.

 

Not finding anything on the code 26...... If you have another PCM to try, think I would give it a shot.

 

I found the code on the allpar site because the 26 code is not in the repair manual.

 

Ok, PCM is not seeing adequate voltage on the injector ground circuit.

Clear the codes, try again, see if anything interesting comes up.

The alternator IS charging the battery, right? (right about 14 volts or so at idle?)

 

I will check it tomorrow sense the alternator is the only part that is not new.