just about ready to by taurus n engine light came on

[killertiller]

So my boss offered me his 2002 taurus with a dohc motor. He owned it forever n took very good care of it. It ran flawless when he parked it 3 weeks ago. So he started it up n drove it to my house, about 40 miles. He said its was running real bad n check engine light was on. SO i pulled the codes and got this.......p 1131, lack of heat 02 switch bank 1 senser 1 indicates lean...... p0301 missfire on 1.... 0303 missfire on 3.... 0316 missfire on start up first 1000 revolutions. My questions is can a bad 02 give me the missfire codes? Of will the missfires give me bad o2 code? I sorta leaning towards it may need a tune up so got missfires n set off the o2 senser. But then again i am clueless..lol. Any help is appreitiated

[behlinla]

The misfires might cause the O2 stuck lean code. Misfires are not a minor tune up issue. Since you may be dealing with catalytic convertor damage, I would not want to buy that car, especially if you have emissions testing in your area.

[killertiller]

Ya im in one of those states. I gettn car for great price 2002 clean as a whistle all maintained it whole life 157,000 miles n rides like new for 900 bucks. Im sure the price will come down some depending on whats wrong

[behlinla]

Find out when the next emissions inspection is due. He might be selling it because he knows it won't pass emissions and he doesn't want to pay to fix it. Just be aware there might be several hundred dollars in hidden costs for repairs as a result of the misfires.

If the car has misfires, to me it says it was not "well maintained". If it just started doing it as he claims, then the damage might not be too bad if it hasn't been driven with a misfire. Remember you should pull over immediately if the check engine light starts flashing to avoid damage.

[killertiller]

Car is parked at house. This is a good friend, my boss i know exactly how he is with cars. It was fine when it was parked . Just gave him trouble when driving it to my house. He def not full of **** n trying to stick me with car. This guy wouldnt even stick a stranger with a bad car. He refused to take my money till we know whats wrong.I was hoping to fix for few hundred bucks. He selling because it was his daughters college car n she doesnt need it anymore, she bought new car. yes the engine lite is flashing

[Breeves002]

Well once you fix it go ahead and get emissions testing to make sure there was no catalytic converter damage. It may cost a few bucks to get done, but then you will know if you need a new cat or not.

I agree with behlinla, the misfire probably is causing the O2 sensor to be stuck lean. The unburnt gas just goes into the exhaust and is burnt up in the cat. When did he change the plugs and wires last? No lean codes besides the O2?

Read this guide to misfires: How to Understand and Diagnose Misfires

[killertiller]

No lean codes besides the o2. The tune up looks like it was very recent by looks of wires but i will pull the plugs n take a good look tonite. But according to behlinla he says bad tune up wont cause missfires. The car has bad acceleration and when i up to speed n keeping steady pace the car like pops under hood almost feels like bad front end parts but soon as i let off gas or hit gas little bit it stops. I am thinking its driving like a bad cat

[killertiller]

Thanks for that link, gonna do the coil pack test also, whats a cat roughly cost?

[behlinla]

If the car just had a tune up, there's a chance they did something wrong (like routed a spark plug wire incorrectly or didn't push a wire on completely). Double check everything. But I would do the spark test to check the coil.

New catalytic convertor is about $300 plus labor.

[killertiller]

tune up looks recent not just done. Like i said he and his daughter drove it daily. Parked for three weeks n when he started it it ran rough and on way to my house check engine light started blinking. Will a bad wire or plug cause a missfire code? According to first reply in this post it wont. I doin the coil check and gonna pull
plugs today right after work.