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Cali smog

Discussion in 'Technical, Maintenance and Modification' started by Joshua, Jan 21, 2018.

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  1. Joshua

    Joshua New Member

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    just need advice on my fox not passing smog, it has super high HC, compression is great and timing. can all my smog equipment being bad cause this? Some valves on the hose off the pump are melted on the inside and idk but seems like the pump is now blowing that much with the hose off. Codes I have are for (Thermactor air diverter and Thermactor Air bypass) PLEASE HELP I MISS HER AND SHE IS JUST PARKED DYING AWAY
     
  2. ALMOST STOCK

    ALMOST STOCK Active Member

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    HIGH HC


    No guessing, no maybes, here's what you need to do:

    How to pass emissions testing:

    High NO - high combustion temps - retard timing, check EGR for operation.
    High CO – Rich condition - fuel pressure too high, check O2 sensors, replace air filter, Clean MAF element.
    High HC – Lean misfire, vacuum leak, common misfire due to worn or weak ignition system components. On rare occasions, an overly rich mixture may be the cause. Do the ethanol/E10 fill up as suggested.
    High CO & HC - Cat converters, smog pump, and smog pump controls. Make sure the smog pump has good air output at 1200-1700 RPM

    How to pass emissions testing:

    1.) Make sure all the emissions gear the car was made with is present and connected up properly. That includes a working smog pump and cats. The smog tech will do a visual check to make sure that all the original equipment is present and connected up.

    2.) Make sure that you have fresh tune up with spark plugs, plug wires, cap, rotor, fuel & air filters. An oil & filter change is a good idea while you are at it.

    3.) [Dumping the computer diagnostic codes on 86-95 Mustangs

    Revised 26-July-2011. Added need to make sure the clutch is pressed when dumping codes.

    Codes may be present even if the check engine light hasn’t come on, so be sure to check for them.

    Here's the way to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great. You watch the flashing test lamp or Check Engine Light and count the flashes.

    Post the codes you get and I will post 86-93 model 5.0 Mustang specific code definitions and fixes. I do not have a complete listing for 94-95 model 5.0 Mustangs at this time.

    Be sure to turn off the A/C, and put the transmission in neutral when dumping the codes. On a manual transmission car, be sure to press the clutch to the floor.
    Fail to do this and you will generate a code 67 and not be able to dump the Engine Running codes
     
  3. Joshua

    Joshua New Member

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  4. Joshua

    Joshua New Member

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    Just my left bank is at 1345 hc failing my smog
     
  5. Joshua

    Joshua New Member

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    Could it be my smog pump tho? It doesn’t really blow at all with the hose off and all the valves in the hoses are melted completely
     
  6. ALMOST STOCK

    ALMOST STOCK Active Member

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    IT's a good possibility that it could be the smog pump
     
    Last edited: Jan 23, 2018
  7. wbrockstar

    wbrockstar Qwik Enuff 4 Me

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    The smog pump & tab/tad valves will have to be replaced if they're not functioning correctly. The catalytic converters wont work without fresh air from the smog pump.A smog pump thats sitting on a shelf or bypassed with a shorter belt will seize up if it sits too long without being ran,so if you buy a used pump off Ebay or the junkyard,make sure it spins freely & outputs enough air for proper operation.Ive got one thats been on the shelf for around 9 months and it sounds like you're grinding coffee beans in it,so its shot.
    The upper cats dont use smog pump air,but the lower ones do.They will clog & fail without a proper functioning smog system.Check the smog crossover pipe too,bolted to the back of both heads.Its known for getting clogged with carbon and the thermactor passages do the same where the pipe meets both heads.
    If you run a koeo/koer test,codes 44 & 94 will usually pop up,if something is amiss with the smog system and/or the crossover pipe or thermactor passages are clogged.
    Smog pump air is sent to the heads through the crossover pipe during warmup mode then its sent to the lower converters through that metal pipe while the engine is at operating temp.The tab/tad solenoids send vacuum to the tab/tad valves,which you said are damaged.
    (TAB solenoid)
    Vacuum On= tab valve sends air to diverter valve.
    Vacuum Off= tab valve dumps air out of its silencer ports.
    (TAD solenoid)
    Vacuum On= tad valve sends air to the heads through crossover pipe.
    Vacuum Off= tad valve sends air to the converters through the pipe.

    The egr system is also part of the emissions system,but it functions totally separate from the thermactor/smog system. The egr valves opening causes lower combustion chamber temps,a leaner fuel mixture, added timing advance and lower NOx emissions. If any component within either one of these systems is faulty,it will cause you to fail the emissions test.

    The following link goes into great detail about the components and how they work plus how to test each system. It'll teach you the ins & outs of both systems.Once you open the link,scroll to post #10 and start reading.

    https://www.stangnet.com/mustang-fo...e-plugged-in-but-no-vacuum-hose-to-it.477938/
     
    Last edited: Feb 3, 2018

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