Hey everyone, I am trying to help out my frined with an 85 bird with a 2.8l.
He had the engine replaced last year and got a new exhaust system and fuel injectors and o2 sensors but reciently his car has been runing really rich, he says when he lets the car idle lots of carbon and unburnt fulel will spit out the exhaust pipes and he has been getting not so great mileage (18mpg) with a 5 speed. I would really apreciate any info you guys could give me. I am working with TPI on my car so I don't know as much about the v6s
thanks

Evan

 

Back to the basics - timing and ignition. Check the whole ignition system, he's probably misfiring on one cylinder. It's totally possible to run on 5 and never know the difference (I did when I first got my car, the #3 wire had melted to the exhaust, realized it after about 3 weeks of "Man this car really is a dog".)

 

Well, the engine controls are basically the same between V6 and V8 cars. All the same sensors, so just take what you know about the 8's and apply it to the 6. the only difference is displacment.

Misfire is the first thing you want to check for. once you have determined that the ignition system is woring properly, check for any kind of leak that would let outside air into the exhaust. That'll make the O2 read lean and it'll just dump fuel like a crashed oil tanker.

After you do a complete check of the basics, it's time to start in on the computer diagnosis. Check the O2 voltage. Is it switching or is it stuck rich or lean? Stuck lean will obviously tell you that there is a problem in with the O2. If you know you're running rich and the O2 says it's lean, something is obviously wrong.

If the O2 is stuck rich, then you know that the O2 is trying to tell the computer to take fuel away, but the ECM isn't listening or doesn't care. That's usually a sign that you're not making it into closed loop. What temperature T-Stat is in it? You might also have a bank of injectors that is shorted to ground, causing them to be full open all the time.

Start with the basics, then move up the electronic food chain from there.

 

Maybe.....

stuck open / bad cold start injector

 

if it looks anything like my pic, the tps is outawhack

 

thanks for all the good info guys, I will make sure my friend get it.