I have searched all the forums and maybe I just did not use the right keywords or phrase but I could not find an anwser to my question. And sorry if this is not posted to the right spot. Also sorry for the length just trying to provide enough information.
I have another good technical question for the 5.0 Mustang Forum. First a little background on the situation, I picked up a four cylinder 89 Notch for 600.00 minus the motor and trans and performed a V8 swap (AER manufacturing 306 long block, FRPP E-303 cam, FRPP 1.6 rockers, FRPP 24 lb injectors, 70 mm TB, FRPP Tubular intake, BBK shorty headers, H-pipe, MSD billet distributor, MSD A6L, MSD coil) replaced the computer with an A9L, complete engine wiring harness, fuel injector harness, headlight wiring harness with a 3G alternator upgrade, all were from an 89. None of the harnesses have any splices or repairs made to them other than where I adapted the alternator upgrade, all sensors, switches were installed new.
And now the Question, I get a check engine light coming on after driving it 10-20 minutes, if you shut the car off and start it right back up it does not come back on until after 10-20 minutes again and the local auto shop is unable to pull any codes because they cannot communicate with the computer. I switched the computer out from 89 notch with my 89 convertible and they can read it there fine. The car runs fine until the check engine light comes on then it runs sluggish. I drove the car for about 300-400 miles before check engine light problem started.
Any help on this is greatly appreciated.
I think that was your power.test fa7 if less than 1 goto fa9.check ac input? Unplug 60 pin key on eng off dvom set at 20v scale ck volts pin 10 and cha grd.is volts more than 1v?if yes service short to power in ac clutch circuit.if no rerun quick test .when u tested 30 to cha.if more than 1v goto fa8 ck neutral drive switch.key off dvom set at 200ohms .unplug harness at nds and measure resistance across the switch less than 5ohms?if yes service short in vehicle harness nd circuit.if no replace nds
Mercedez, the problem so far was the ground wire for the HEGO was broken inside the insulation and once that was repaired and I regrounded it to the firewall it cleared up the code issues except for the code 67 which hotcobra03 and HISSIN50 have been providing great information on how to troubleshoot and try to fix.
How do I test the Neutral safety circuit failure code 67, to see if the switch is bad, because it looks like that could be the cause of the problem? Pin 46 which appears to be the wire causing the problems ends at the Neutral switch. I can not find any breaks in 46 going anywhere.
Thanks
hey you have a safe holiday too ....took all afternoon too read up on this,something here has been overlooked or missed between me getting in the way,,,at first i was stuck on harness also but after learning the circuits it should work,but like the ac and cruise and manual harness combined together could be where problem lyes.. the test on jumping orange to pin 30 will tell what code 67 is,, cant remember what results were or if it was done yet,,, just the test at pin 30 before using jumper.iirc you failed it and jumping orange for power to pin 30 and see if code 67 goes away,,hope so ,if not maybe start back at beginingThanks hotcobra03 and HISSIN50 for the time and help, sorry I have not added any new responses. I got the AC pressure switch from all my AC stuff I took out and hooked it up and cleared the computer and it still shows code 67. So it is either the NDS switch on the trans or the computer harness I got came out of a standard. I did a mass air conversion on an 87 and never worried about wether the harness was a standard or auto and never had any codes because I was told the harness did not matter as long as the correct year was used, ie 1988-1990.
Anyways thanks for all the help and time you two spent trying to help and hope you both have great holidays and I will update this when I get working it after the holidays.
Does anyone have a better wiring diagram for the O2 sensor harness for both the manual and auto? I was told that they are different and that the wrong O2 harness could be causing the code 67, and could cause the computer to ground out internally and I am not sure which O2 harness I have. All I have been able to find so far is a different part number for each but I dont have a part on mine.