engine light comes on

[pao_X]

When I turn the engine on, idleing is good, about 700, then when I press the gas pedal up to 4-5000 REV and depress gas pedal, REV goes down to 4-500, and engine light comes on, then engine start hesitating, almost stopping. After about 30-40 sec, engine light turns off.
It still does it with a brand new installed "accordion" hose between the VAF and the throttle body.

A mechanic told me it may be the O2 sensor. It is quite expensive. Could be something else?

Automatic, V6, '93

[mxmaz]

Go here, this tells you how to test your engine for codes. Its very easy
http://www.mx-3.com/ubb/ultimatebb.php?ubb=get_topic;f=23;t=000005

As far as an o2 sensor being expensive... there is a write up in the v6 faq on how to do it yourself, and i was looking as the universal ntk o2's on ebay for $36 usd. so its not bad at all
here is the sensor
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7920027503&category=33557&sspagename=WD1V

hope this helps

[pao_X]

Thank you for the answer.
I will test engine for codes first.