New guy with questions, HELP!!

[tim's wag]

Hi, I'm new to this forum and I need a little advice. I have a 92 C1500 5.7l pickup, yesterday while driving I had the "service engine soon" lite come on. This has never happened before. The truck has been running kinda rough lately, idle has had a very noticeable problem. It used to idle very smooth but now it's rather rough. I haven't changed anything parts wise in qutie a while, so I'm planning on doing a basic tune up (plugs, wires, cap, rotor, fuel filter, and such). I guess my biggest question is, which computer diagnostic system does my truck have? Is it OBD-1 or OBD-2 or something else entirely? I have an OBD-1 scanner that I use on my 94 Caprice wagon and I was hoping that I could use it on my truck to find out what's going on with it. Any advice would be greatly appreciated! Thanks for your time and help. Tim

[TarheelZ]

Tim, I think 1996 was the 1st year for OBD-II so your's is probably OBD or something else. If you have an Auto Zone near you, they will scan the codes in your truck's computer to tell which codes have been recorded.

 

Good luck!

[100R1]

OBD-1

 

Check your 02 sensor if over 100K miles

[tim's wag]

Thanks guys! I will hook up my scanner today and I'll definitely check out the O2 sensor. Truck has 112,000 miles and never replaced anything other than normal maintenance. Thanks for your help, again. Tim

[96Z71asskicker]

Check your 02 sensor

That's a good chance of what's wrong with it my check engine light is on because of my O2 sensor. and i have lsot some power it feels like.

[tim's wag]

Just got done scanning it and guess what, code 44 O2 sensor lean. You guys are on it. I shall get a new one tomorrow. Now how do I clear the code out of the computer? My scanner won't do it, will it just clear itself?

[02 Silverado Z71]

After you replace your oxygen sensor, disconnect your negative battery terminal for a few minutes. That will clear a code on OBD-1 vehicles.

 

You said your idle was not smooth. Sounds to me like you have a vacuum leak under the hood, which also will give a code 44.

 

If you had a code 13, I would say go straight for the o2 sensor. But since you have a 44, double-check that you have no vacuum leaks. Also check how your EGR is operating. I just have a gut-feeling that you also have a vacuum leak.