Running rough and rich

[1989DropTop]

1989 5.0 Convert, Auto, Just had Heads machined, new head gaskets, water pump, plaugs cap rotor, wires, etc... Ran codes tonight and got 12,21,41,91. Where are the O2 sensors located on these things. I am new to owning fox Bodies. This one runs like crap while at low rpm runs like a raped ape when your foot is in it. Has a mickey moused exhaust from previous owner. Has flex tube before and after the mufflers.


I know code 12 is idle is too high but it is sitting at 750
41 and 91 are o2 sensors
and 21 is coolant sensor out of range. Where is this sensor located???

 

[jhr302]

i think the coolant sensor is on the heater tube ( two wires ) on the passenger side front , should be right behind your oil fill

 

[1989DropTop]

Thanks I will track it down

 

[jrichker]

The cone air filter in the engine compartment is a big no-no. The hot air from the engine & the turbulence created by the fan upsets the airflow through the MAF. That upsets the air/fuel ratio , performance & gas mileage. You would be much better off with a stock air box and a flat panel filter.

Whatever you do, relocate the air intake to the fender well where it can pick up cold air.

 

[1989DropTop]

Thanks for the tip the cone can was on the car when I got it and I am searching for a stock intake set up for it. I hate the cone crap.

 

[IH8BOWTIES]

I've never thought of painting the plenum like that. It actually looks kind of cool. Jrich is right though. Get that intake into the fender well. I recommend the bbk. They perform great and have that ominous "whistle" when you're coming out of the throttle. Everyone knows your 5.0 is breathing good and means business. The only drawback is you may suck a little water in the rain on the highway and she'll buck pretty good. There are others that have the shroud around the breather to help eliminate that but I love the bbk's. After all, how often am I on the highway in a heavy rain? Just sayin.....

 

[1989DropTop]

I am going to take it to the exhaust shop and get a qoute on replacing the wannabe exhaust. Then will retest and see if it helps Cone can is gone got new BBK for it. Thanks for the help Guys

 

[1989DropTop]

Jrich, I wanted to say thanks for the tips!!! I yanked the cone filter off and wow did the car come alive. I have a make shift intake on it right now that runs to the fenderwell. I still have check engine light on for the o2 sensors but what a difference in running . Thanks Brian

 

[jrichker]

The best cold air intake is the stock airbox, use a high flow paper or K&N filter. Be careful and do not over oil the K&N, ot it will cause problems.