I have a 1993 xlt 4x4 5.0 auto trans f150. I purchased the truck not running (needed an engine rebuild) the truck has had a recent full true dual exhaust with no cats--they just left the smog pipe hanging loose under the truck. I have rebuilt the motor and am ready to reinstall but the smog pump doesn't turn to good. figured it is useless with out the cats anyway so I am thinking of bypassing what is left of the smog system. has anybody done this before? looks like a shorter belt and some brass plugs at rear of heads will bypass most of the stuff. the Oxy sensors will remain in place in the exaust manifold. will this cause any computer issues, or mixture issues. Found some info on the mustang sites assuming there smogs system is simmilar with the trucks. this is basically just a stock application not high performance, truck needs to be driveable any suggestions or help... thanks PS there is no emissions testing were i live--(or inspections for that matter)

 

Short answer: There are no problems doing this. The air pump system has nothing to do with running the motor. Yank the solenoids (TAD, TAB), air pump, plumbing etc. and block off the passeges in the heads.

 

Hey thanks where are those sol tad and tab? is one or both on the lower intake?

 

Neither is on the intake. They should be near the coil along with the EVR. 3 solenoid packs in a row mounted to a little metal bracket...can't miss them.

 

Thanks -- I think I know now they are on a plate on top of the driverside valve cover with the coil.--thanks again for your help!!!

 

you don't even have to yank em...I got em pluggedin but pluggedoff..tjhat way it don't throw no codes.....tobypass the smog..pull the pulley off and get a shorter belt...you'll need bolts for the back of the heads...put some copper rtv on the threads and put em in there...should be 9/16 bolt shaft with course thread...get the shortest ones possible...you can yank the vacuum canisters and vapor canisters off while you're at it...got anymore questions or need some pics...checkout my gallery or just ask me for some other pics....I just got done doing this to my truck last week.....Luck

JR

 

Thanks --pics look good like the red intake and vc

 

Yeah, the solenoids by the coil leave electrically hooked up, just plug the openings.

The divertor valves next to the intake (between the intake and driver's valve cover) can be yanked, the big coffee can by the battery, etc, etc, etc.


it's damned amazing how clean the engine bay looks with all that crap out of there. I recently put a 96 engine in my 88, and the emissions crap is all different... it was MUCH easier to remove it than to buy all the crap i'd need to add to get it to work.

thank god i live in a state with no emissions testing...

 

Thanks woody...the red is the same as the factory color on my truck...Like I said...if you need any additional pics...lemme know, I'll be glad to snap a few more.Luck

JR

 

Whats the point to leaving the solenoids in place if they arn't doing anything other than cluttering the engine bay? There is NOTHING wrong with yanking them. You might get an informational continuous memory code just to let whomever is reading the codes that solenoids are gone / not working, but thats it. The motor will run the same whether those codes are there or not. Hard codes are the ones to worry about and NOTHING about the thermactor system will give one of those.

 

It still turns on that stupid light, which I would like to reserve for occassions when something else might be acting up. You're right- the truck won't run any different.

But those solonoids are VERY small in comparison to the whole thermactor system. They are barely bigger than the connectors that plug into them, and they are half hidden under the bracket for the coil.

The passenger side of the engine bay, however... you could smuggle a small guatamalan boy across the border with the space that frees up.

 

Thats contrary to my experiences and what I was told by the tech support at Ford Racing...but then I am dealing with a 89-92 mass airfow Mustang computer which may or may not react differently to this. It was my understanding that it did not matter what computer is used because no hard code = no CEL and those solenoids can not throw a hard code.

 

HEY ANOTHER PERSON FROM NH!! haha we do have inspections here BUT only the saftey not emissions unless it is 96 or newer . there shouldn't be a problem performance wise if you remove the smog pump

 

It is possible that something else was throwing the light, actually. This is all experience based on the engine that WAS in my truck. I had disconnected all the smog equipment but had accidently left a few vacuum lines unplugged.


It was throwing a check engine light because of it, but I think indirectly. I think the vacuum leak in the system was messing with the idle mixture somehow. So it's possible the solenoids were not causing it. All I know is that it stopped when I plugged them.

On the engine I recently put in, there is not a spec of emissions equipment on it. I should get it running some time tomorrow. I'll play around with the solenoids and see if I can get it to throw a light depending on how they are connected and post back up....

 

Thanks I didn't update my info I moved to South Carolina and there is no inspections at all--which is a bit of a shock. I am glad to be away from having to shell out 20-25 bucks for a yearly inspection sticker and hope the garage was not going to be too nit picky. The flip side is down here some people drive them in any condition bald tires etcc I even saw a truck with a pice of plywood and out door carpeting for a hood. thanks for the help