I have an 86 F-150 5.0 EFI and i was wondering if i remove the air pump, do i gain or decrease horsepower???? and another thing if i do remove it, how will the truck run????? better??? same??? worse???

 

Even removing the belt will cause the computer to emit an error code, possibly causeing other code problems to develop (that awful code 31 is still troubling me...)
and I for one wouldn't recommend it, that air pump moves cool air into the exhaust to help the combustion fuel/air ratio and among other things that keep that 5.0 EFI engine running smoothly... the O2 sensor also uses the air pump into the exhaust to sample the fuel/air ratio's and it reports its finding to the computer which makes you use more gas (rich...fuel means rotten egg smells with other bad omens) With gas prices as high as they are, I would welcome my air pump back into my EFI engine....

 

What about if you have no computer? (Holley 4bbl)

 

What can i do to fix things, When i got my truck, i'm not sure if it broke and the person just unhooked it, or if he just wanted more performance, but anyway, my truck eats gas like crazy, is there any modification, or anything i can do to bring gas mileage up without hunting down an air pump, like an aftermarket 02 sensor made for it, or somthing. Just a question, if air wasnt being pumped into the exhaust, wouldnt that make the computer think the engine was running rich, and adjust things by leaning out the mixture?

 

If you don't have EFI or a catalytic converter, removing the air pumps won't do you any harm. I have an 86 F-250 and I removed the AIR pumps and all of the smog equipment and the truck actually runs better without it than with all of that stuff. Mine is a NON-catalyst but if you do have a cat, it could ruin it quick, fast, and in a hurry.

 

You can unhook the air pump and you won;t have any problems, atleast i didn't, all it;s there for is to add air to the catalytic converter so that it burns up the excess hydrocarbons(fuel). It has nothing to do with the o2 sensor, that;s why the air pump hose is routed straight into the cat so the o2 sensor isn't having all of the fresh air flowing over it, which would cause it stay on the lean side, then the computer would see that it's reading lean and put more fuel in then that;s when you would run lean and smell like eggs, it would also burn up to cat also.
Also the air pump has nothing to do with aiding combustion and pumping cool air to the combustion chambers or anything, the only time it;s putting air into the intake is on cold start up to get up to operating temp. In short, it makes no diffrence if you take it off, at least not on mine.

 

Locknkey, shim the EGR sensor shaft ( on top of the EGR sensor) this will get rid of the Code 31.
Reamer

 

Ok, thanks Reamer...but I already had tried that, and have already settled in the fact that until I put another Air Pump (Yes I'll find one someplace thats not junk...)And put the air tubes back into the block and replace the exhaust manifolds with the ones that are supposed to be one the 302 EFI engine..it should be possible to have the code 31 gone.

On another note, I disagree with the others about what they said, but thats why everyone has their own way of understanding different situations about how things work in relation to the sensors.. below is an part of what I was talking about...
Quote:
" Always begin diagnosing a driveability problem in a computerized vehicle by retrieving the codes first. Hard codes, (check engine light on) will give you an obvious starting point. Soft codes (engine light was on intermittently but is not on at the moment) will also give you a good start for diagnosis. Keep in mind that a code is an indication of a failure or the result of a failure. For example an O2 sensor may be constantly showing a rich condition which will trip a code. The sensor may or may not be the problem. The problems, may be in a system that could cause a rich condition. The same goes for lean O2 sensor readings.
Oxygen sensors can set trouble codes for various reasons. An open sensor wire can set trouble codes. If a sensor stays lean or rich for a long period of time, lean or rich codes may set. In either case, the sensor may be at fault. Before condemning the sensor, there are some very important checks that should be made.
For continuously lean O2 sensor readings:
1. Check sensor output wire for possible grounding. A ground will cause a false lean signal.
2. Check the MAP sensor for proper vacuum to voltage output. A high vacuum signal will cause a lean ecu reaction. (Don't forget to check manifold vacuum first!)
3. Clogged injectors can cause a false lean condition. A cleaning may solve the problem.
4. Water contamination will cause a lean condition.
5. Low fuel pressure will cause lean conditions at any rpm or load range. Be sure to check pressure at all driving modes.
6. Exhaust leaks, especially near the sensor can pull in air and cause a false lean reading.
7. Check for proper air injection system operation. The air pump should not direct air to the exhaust ports during closed loop operation.
For continuously rich O2 sensor readings:
1. Check the fuel pressure. High readings will cause rich conditions.
2. Leaking injector(s) will cause rich exhaust.
A leak down test and/or a power balance test can usually reveal the leaker.
3. A contaminated or malfunctioning canister purge system can very easily put uncontrollable amounts of fuel into the intake manifold. Simply disconnecting the vapor hose can reveal this as your problem system.
4. Check vacuum to voltage readings at the MAP sensor. A low MAP output will cause a rich ecu reaction. (Don't forget vacuum readings again!)
5. A false tps signal can cause the system to go rich if the Ecu sees a high tps output. Check tps readings at idle and for a smooth rise to wide open throttle.
Remember that the O2 sensor can help you simplify your diagnosis and help you avoid frustration!"
I can't give credit to whoever wrote that above, but to me it makes sense and I agree with it.