Hey all, I just joined this forum, thanks in advance for your feedback! I just attempted to smog my 95 Disco and it failed badly. Moreover, the mechanic was not able to get a read on the scanner. He suspects there is a ground problem but has no idea how any hours it will take to diagnose (may need to remove dashboard). I know this disco (5-speed) is rare and would prefer not to junk it (may consider selling but need to pass smog first in CA). It drives and the engine seems okay besides the electrical problem but there are numerous repairs long overdue. Some of them I can handle but the electrical seems daunting. Has anyone encountered a problem with the test codes not being accessible? Any ideas on where to look for a ground problem? Dig into the electrical schematic? btw, I checked the fuse for it and it's okay.

 

It's OBD1 so there is absolutely no way to pull OBD2 style codes off of a 14CUX based 89-95 RRC/D1/D90. All they can do for SMOG is place a sniffer up the tailpipe and see if it meets the specs for 95 emissions.

 

You need a new smog guy if he doesnt know what year obd2 started.

 

Forget the 'electrical issue'. It is highly unlikely to be your problem (if it exists at all).

When was the last time you changed air filter, spark plugs, plug wires, and distributor rotor? After that the next step is to 'sea foam' the intake.

 

Thanks for all the responses. It's nuts that both the smog shop and the LR mechanic failed to realize this was OBD1 (at least they didn't charge me for their ignorance).

I realized late yesterday (from reading the forums) that the codes are OBD1 and read the CEL failure code 44 under the passenger seat. Code 44 is HO2S Left Bank. That's the left bank for the heated oxygen sensor. My understanding is this can fail because of the a bad sensor (usually upstream from the catalytic converter) or any number of issues that could cause the fuel mixture to be compromised (plugs, electrical, etc.). My plan of action is to check the plugs and the O2 sensors first. The vehicle has 121K and I don't believe the O2 sensors have ever been changed (I recall CEL for emissions upgrade around 80K).

 

WaltNYC, thanks for the pointers. I hadn't considered cleaning the intake, will try that if the other options fail.