97 tahoe 200xxx multiple monitoring system issues???

[sammittrue]

Just looking for some insight if any one has any suggestion feel free to chime in. Not very familure with the tahoe mostly worked on german and rice burners so please forgive. My friend brout me his 97 tahoe with a check engine light and 200xxx. It did not give me a actual code but seems pretty much all moniter sytems lit up such as
-misfire moniter
-fuel system monitor
-comprehensive componant monitor
-catalyst monitor
-o2 sensor monitor
-o2 sensor heater monitor
-egr monitor
He said it runs fine most the time but on occasion under load it will run really rough
I havnt done anything to it yet i was just planning on a tune up to start but i know with most german cars this usaully means some kind of computer issue?!
Any suggestions would be great. thank you

 

[Slammed]

It's hard to say it's so many things that can cause this even lack of good fuel pressure but I'd start by cleaning maf sensor and then i suppose full tune up then fire it up after clearing codes then see if she drops any new codes if she does then the next step would be catalytic converter if still bad then spider injectors

 

[sammittrue]

Sounds like a plan to me! thanks for youre time ill update as i go..

 

[lesterl]

Get codes, watch fuel trims while under load and acting up. I agree with the tuneup and cleaning of the MAF sensor, be careful with the MAF, but I usually use a qtip to carefully wipe the sensor wires off- do at your own risk there.....

When replacing Cap and Rotor, get OEM stuff..... Avoid Bosch plugs. NGK plugs or OEM Delco/ Delphi are good.