obd1

[3ace]

Does anyone know of an OBD1 reader for a 1991 Chevy Suburban 6.2L that doesn't cost an arm and a leg? Thanks. :)

[convert2diesel]

How about a paper clip? Cross out the data slot to ground, turn on the key and count the flashes of the SEL. The older OBD1 readers do little more then read codes anyway so why not just the paper clip?

Bill

[JohnC]

What's there to read? My '93 only had ABS data.

[3ace]

How about a paper clip? Cross out the data slot to ground, turn on the key and count the flashes of the SEL. The older OBD1 readers do little more then read codes anyway so why not just the paper clip?

Bill

I did the paper clip trick and came up with a code of 12 which is supposed to mean a normal system. When I start the truck for the first time of the day and it's idling the check engine soon light flickers and sometimes will stay on solid. If I give the engine more rpm's the flickering or sometimes solid light will go out but if I go back to idling the light will do one of the other again. After a few minutes of warm up time and I drive off the light usually will go out until I hit a stop sign or stop light and go to idling again. When the engine reaches normal operating temps the light will remain unlit. Do you believe I'll be okay this way until such a time the light will stay on solid and the ECM/PCM will hold a good fault code? Thanks. :)

[Robyn]

Likely its a problem with the EGR solenoid, EPR solenoid or possibly the TPS switch on the IP

The EPR regulates exhaust pressure in the LH manifold so that the EGR can work.

Either solenoid if bad can cause the SES light to come on.

The Coolant temp switch could also do it.


These older systems were a tad sketchy at best.

One thing about this is that whatever it is, the issue will not leave you stranded.

The IP is all Mechanical and the computer has little to do.

Depending on the tranny (either 700R4 or TH 400) the computer controls the converter clutch on the 700 but nothing on a 400.

Most likely the EGR/EPR setup

Try unpluging the solenoids and see what gives. A short will cause a fault but unhooking them may give you a clue as to which one is bad.


Keep us posted

Missy

[3ace]

My xmsn is a 4L80-E, would that make a difference in diagnosing? I also just had a new IP installed about 1 month ago. Thanks. :D