Ford AIR injection system

[AppleBoy]

So I am looking at dealing with my leaking AIR injection system. A few things on my old 5.0L need replacing. Mainly the air charge sensor, in order to replace this sensor I have to take the intake plenum off the motor. While I am at that I might as well replace everything thats on its way out.

While the intake is apart, I am planning on changing ACT sensor, EGR valve and EGR tube, AIR injection tubes, upper intake gasket, and who knows what else I will run into.

Now before I replace the AIR injection tube(s), I want to see about other sollutions. Is it possible to delete this system and plug of the ports? is there a performance increase/decrease? and also if its possible to do this, what is the impact on emissions. Here in Ontario we have smog tests. Ad one more thing, IF its possible to delete this system, would there be any harm to the catalytic converters...

Just want to know before I go hunting for cheap parts, finding anything for the air system seems to be a pita.

[AppleBoy]

Also does anyone have any experience on changing those tubes back there? how many are there, and any link to a diagram or place to buy the specific tubes?

its a 94 f150 5.0L

[punisher]

I do know removing it will set a ck eng light. The ECU commands upstream air and checks to see if the O2s go lean. Cold emissions will go up for sure, it will take longer to go into closed loop.

As far as replacing parts, I don't know what to tell you. I usually leave EGR systems alone unless I have a code or a leak, screw in EGR tubes sometimes sieze in the EGR valve, and they don't come loose....ever. AIR tubes are usually a pain, I don't have any good news to tell you on that job except patience and a good line wrench with penetrating oil. I have seen AIR tubes aftermarket, the other components are usually dealer only.

If you need diagrams, give me some time to dig out some manuals.

[Ezekial]

I pulled all the shit on my 93 F150, but left the pump as it was needed for a pully.

You'll want to get a couple plugs for the rear of the heads, I forgot the size but you should be able to find out online. There is a crossover tube at the back of hte heads with a bolt on each side, unscrew them and remove the tube. Then use the plugs to plug the 2 holes. Remove the rest of the crap, along with the canister. You can get a dummy pully for where the AIR goes if you want, but I was cheap at the time. You may be able to short belt it, but not sure on that.

:edit
oh, smog bs...
yeah. you may want ot keep it. I believe the point is to feed oxygen to your cats so they can heat up.
I had removed my cats, plugged my egr, and just gone to town on everything pretty much.

[jarhed13]

edit: n/m

revised google terms answered my question

[[H]ard|On]

There is on performance impact at all

The extra 02 helps get the cats hot faster, that's about it

My old tree friddy had one-way check valves on the stock exhaust mani's and i remember just pulling them off with no ill effects.

Less clutter, looks better, may slightly lower parasitic loss if you remove the air pump.. that's about it.

[AppleBoy]

Originally Posted by punisher

I do know removing it will set a ck eng light. The ECU commands upstream air and checks to see if the O2s go lean. Cold emissions will go up for sure, it will take longer to go into closed loop.

So this could be my main problem I have been having for a long time...

My truck HAS to warm up before I leave the parking lot. Otherwise it chugs and uses gas like crazy. I have to very specifically warm it up till the needle at least hits the first mark. Once it hits that first mark the truck runs fine, its like a switch turning on (going into closed loop finally) With temps hitting -20 - -30 this can take 5-15 solid mins of warming up.

So far I have replaced the maf and the ect sensor, no change other than a bit better fuel econ.

I have an exhaust leak sound (I have told you about this problem before) but its only a leak sound when the truck isnt warmed up and it isnt in closed loop mode. Once warmed up I can hammer on the throttle and I dont really get the leak sound.

Is my air injection tubes rotten and leaking causing the truck to take a long time to go into closed loop mode?

[AppleBoy]

So just to get a visualization, I *think* my truck only has one cat, at least from what I remember I only remember seeing one cat on the y pipe.

so a tube runs from the cat up the rear of the motor to a check valve? if thats right where does it go from there?

I have access to a lift, torches and tools. is it hell getting at these connections? would rather not have to drop any of the exhaust.

[Ezekial]

Originally Posted by AppleBoy

So this could be my main problem I have been having for a long time...

My truck HAS to warm up before I leave the parking lot. Otherwise it chugs and uses gas like crazy. I have to very specifically warm it up till the needle at least hits the first mark. Once it hits that first mark the truck runs fine, its like a switch turning on (going into closed loop finally) With temps hitting -20 - -30 this can take 5-15 solid mins of warming up.

So far I have replaced the maf and the ect sensor, no change other than a bit better fuel econ.

I have an exhaust leak sound (I have told you about this problem before) but its only a leak sound when the truck isnt warmed up and it isnt in closed loop mode. Once warmed up I can hammer on the throttle and I dont really get the leak sound.

Is my air injection tubes rotten and leaking causing the truck to take a long time to go into closed loop mode?

as far as I know, the air injection system really doesn't do much of anything for making the truck run like shit or not. It's only purpose is to heat the cats, and is seperate from the computer system. From your problems noted, have you looked at your temperature sensor? That seems to be the number one sensor with the Fords I have owned in the past (80s/90s models). I would also take a look at the TPS, but don't really think that's it. Additional the 02 could be fucked, not heating up ike it's supposed too, or something along those lines.

[Ezekial]

Originally Posted by AppleBoy

So just to get a visualization, I *think* my truck only has one cat, at least from what I remember I only remember seeing one cat on the y pipe.

so a tube runs from the cat up the rear of the motor to a check valve? if thats right where does it go from there?

I have access to a lift, torches and tools. is it hell getting at these connections? would rather not have to drop any of the exhaust.

unless someone has modified it it should have 1 cat immediatly after Ying just next to the tranny. The 02 sensor is right here as well, and is BEFORE the cat. Then a single pipe comes out of the first cat, travels a foot or two and goes into a second cat. After that it travels down the frame to the muffler and rear pipe section.

When I did a full build on my 93 F150 I went with longtubes and custom exhaust



Original exhaust (cut after the first cat)

[Ezekial]

Originally Posted by AppleBoy

So this could be my main problem I have been having for a long time...

My truck HAS to warm up before I leave the parking lot. Otherwise it chugs and uses gas like crazy. I have to very specifically warm it up till the needle at least hits the first mark. Once it hits that first mark the truck runs fine, its like a switch turning on (going into closed loop finally) With temps hitting -20 - -30 this can take 5-15 solid mins of warming up.

So far I have replaced the maf and the ect sensor, no change other than a bit better fuel econ.

I have an exhaust leak sound (I have told you about this problem before) but its only a leak sound when the truck isnt warmed up and it isnt in closed loop mode. Once warmed up I can hammer on the throttle and I dont really get the leak sound.

Is my air injection tubes rotten and leaking causing the truck to take a long time to go into closed loop mode?

more on this.... it could be a cracked exhaust manifold... they are notorious for cracking on these trucks. My 88 did it and would sound like shit til it got about a 1/4 way up, much like you. After that the heat would pretty much fully seal the crack. It was fine like this for a quite a while and didn't cause me any issues.

I always had shit problems like these with my 93 and worked most of them out, but then sold it lol
I replaced many sensors and ended up replacing the comptuer AND wiriing harness to fix the remaing peicies. After this I had it narrowed down quite well to like 2 sensors but sold it before I fixed it.

I am still guessing it may your temperature sensor (not sending unit).

[AppleBoy]

Originally Posted by Ezekial

Original exhaust (cut after the first cat)

So thats the tube right there eh?


tempurature sensor.. hmm where is that located? Also I dont think the manifold is cracked, I did recently replace a warped exhaust manifold about 6 months ago or so (right side). After replaceing that it was fine, this seems like a seperate issue.

Also I would think a cracked manifold wouldnt cause the truck to run like shit, only shound like shit. or at least not run noticably worse power wise. It really feels like the truck has not entered closed loop mode at that point.

I have a feeling the air tube is defintaly cracked and leaking, I remember the truck starting to act up like this after I had the transmission rebuilt, I think the tranny guys buggered up the tube in the process.

[Ezekial]

Originally Posted by AppleBoy

So thats the tube right there eh?

tempurature sensor.. hmm where is that located? Also I dont think the manifold is cracked, I did recently replace a warped exhaust manifold about 6 months ago or so (right side). After replaceing that it was fine, this seems like a seperate issue.

yeah, one of the tubes

temp sensor is right near the thermostat housing

[AppleBoy]

Originally Posted by Ezekial

yeah, one of the tubes

temp sensor is right near the thermostat housing

Is that the ect sensor you mean? I got that one done.

[Ezekial]

Originally Posted by AppleBoy

Is that the ect sensor you mean? I got that one done.

yup, that's the one

if you replaced it during this problem diagnosis, any change?
I had a new one on my 93 go bad basically immediatly, and I didn't replace it for well over a year looking into other shit... it was bad evidently