I have a 1988 bronco 2 with 2.9 5 speed i can not get rid of these codes 18 64 67 i have changned parts and get it fixed. Runs like crap until the che

[bf750]

I have a 1988 Bronco 2 with 2.9.. 5 speed. I cannot get rid of the codes 18, 64, and 67. I have replaced parts, fixing what the codes said. Now it pulls out no power. It runs like crap until the check engine comes on, then you feel a surge of power and takes off. Runs great with check engine light on.

 

[rusty ol ranger]

18 (R) Check base timing & advance function
(M) Ignition TACH signal erratic

64 Intake Air Temperature (IAT) or Vane Air Temperature (VAT) signal low or grounded

67 just means it wasnt in neutral during testing (usually) either way i wouldnt worry about this one.


Pull your SPOUT connector and check base timing. Then plug the SPOUT
back in and check to see if the timing mark is moving all around, this will verify the ECM is controlling timing.

The IAT sensor code is im guessing where the problem lies. On the passenger side of the upper intake in the middle runner youll see a plug with a sensor screwed into the upper intake. This tells the ECM the temp of the incoming air and has it adjust the fuel mix.

You can try cleaning the probe on the sensor if its carboned up or what i would do is just replace it. Its like a 15 or 20 dollar part.

 

[rubydist]

These obd1 engines don't run worth a crap when there is an iat code, that has to get fixed. These vehicles are old enough that there are now wiring harness issues starting to crop up. I spend a bunch of time on the SHO forums and in that world, wiring harness opens and/or shorts are not uncommon. So, you may need to check out the wiring between the temp sensor and the pcm to make sure that is all good, because the engine will not run right until that 64 code is gone.

 

[bf750]

Thanks for the help. I got it fixed . Engine harness is the problem