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Emissions deleted

6K views 13 replies 3 participants last post by  wbrockstar 
#1 ·
I delete the entire emission system from my 88 mustang,now I need to know what to do for keep the pcm with no emissions codes.


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#2 ·
Did you delete the EGR as well?
 
#3 ·
Do this for the egr system::
1)Connect the evp harness to the evp sensor
2)Turn the key on
3)Connect a multimeter to the evp Signal & Signal Return wires
4)Manually push the evp sensor rod inwards until the meter reads between 0.24-0.67 volts
5)Wrap some electrical tape around the rod so the voltage will remain fixed between the range listed above
6)Use some superglue on the rod to keep it held in place
7)Use some zipties to attach the evp sensor to something secure so it wont move around
This modification will cause code 33 to store,but it wont cause any driveability issues or a cel.You dont have a cel anyways
on a 88.

If you have deleted the tab,tad & evr::
The following info is by Joel 5.0 @ sbftech....

Buy (3) 75 Ω 3-Watt resistors for the EVR, TAB & TAD solenoids and install one in each solenoids harness plug.
 
#6 · (Edited)
When you say "evr" you mean "egr"?
No.EVR is short for EGR Vacuum Regulator.Its the solenoid mounted on the passenger strut tower,above the tab & tad solenoids.
If youre not bothered by a few codes being triggered during a koeo & koer test,dont bother installing the resistors into the tab & tad harnesses.
The tab & tad wont cause a cel or driveability issue,if theyre deleted,but they can cause 8x codes to be triggered during a koeo test.The resistors will prevent these codes from popping up,but youll still get codes 44 & 94 in a koer test,even after you install the resistors.If you decide not to install the resistors,having codes 8x,44 & 94 is equivalent to a code " 11".......
 
#8 ·
I can install the resistor to the egr plug too? If The egr is deleted can cause drive ability issues too?
Anytime there is a egr system code (31,32,33,34,8x) present,the ecm will delete/bypass egr function in the eec logic,so that the system will be non functional & so the fuel mixture & timing advance settings will go back to normal.The ecm leans the fuel mixture & adds timing advance anytime the egr valve is open & this can cause detonation if the egr valve isnt opening when its supposed to.
The egr delete plug(youve got installed already)or the resistors triangle an be used for the evp sensor harness,but use one method only.The use of the resistors will cause code 33 to be set & its the only egr related code that wont cause the cel to come on.
You wont have any driveability issues due to the egr system being deleted
 
#10 ·
Did you delete the charcoal canister & purge valve too?? If yes,youre gonna smell gas fumes because the purge valve normally opens to allow those fuel vapors to be drawn into the intake,where they can be burned by the engine.If the canister is deleted & that vacuum hose is left hanging in the engine bay,vapors will vent to the atmosphere.If the hose is hanging,you have to leave it open to vent those vapors or you can plug the hose & install a ventilating gas cap(fumes will still be present with a ventilating cap too)
The tank has to vent,otherwise the fuel tank will get deformed,from not venting.

I assume you dont run converters anymore,right?? The combination of no cats + no smog system + no egr system + no canister purge system?? is gonna =exhaust fumes.You might be able to get it on a dyno & have a chip burned to reduce some of it,but Im not sure how much it'll help.

The emissions systems(egr,thermactor,canp)shouldn't cause any driveability issues after theyve been deleted.They will cause issues if theyre intact & a component is malfunctioning though.Did you double check to make sure all of the vacuum hoses/ports are plugged/capped,if they were part of a system you deleted??

Another thing that will cause strong exhaust fumes is a vacuum leak and it can also trigger misfires too.When a vacuum leak is present,the o2 sensor(s) read the extra oxygen in the exhaust & that triggers the ecm to "falsely" richen the fuel mixture, in an attempt to bring the afr back to normal.When this happens,the engine begins running really rich because it really didnt need any extra fuel to begin with.The ecm only added the extra fuel because it was doing what the o2's were signaling it to do.
A vacuum leak can cause a misfire because theres too much oxygen in the combustion chamber at times & the af mixture doesnt get consumed.Leaks can occur in many places like throttle body/egr spacer/intake/IAC gaskets,vacuum hoses,vacuum operated components,fuel injector orings,etc.If you wanna check for leaks::
Fuel Injection Technical Library » Vacuum Leaks
 
#12 · (Edited)
You can also try running koeo & koer tests,to see if any codes are present.A vacuum leak will normally cause O2 sensor codes(41,91,42,92) to store in the ecm.You can run those tests with nothing more than a jumper wire & a test light.Use the connecter diagram shown in the following link to identify the terminals.
Connect a jumper wire between the STI terminal & the SIGRTN terminal then connect a test light between the STO terminal & the (+)battery post,turn the key on & starting counting the flashes on the test light.Convert the flashes into numeric codes & post your results.Do the same for the engine running test.
(Example:: two flashes-pause-seven flashes-pause=code 27 )
The connecter diagram also shows the use of the check engine light or a analog voltmeter to run the tests,but your 88 model doesnt have a working cel,so stick with the test light.
If for any reason the test wont begin by being connected this way,move the jumper wire from the SIGRTN terminal to the (-)battery post then try to start the test again.
BTW-make sure the engine is at operating temp,the ac is off & the transmission is in neutral (manual) park (auto) before you run the tests.
If it hasnt been done yet,clean & modify the 10 pin connectors,like shown in the link.

DIY KOEO/KOER/Cylinder Balance Self-Test Procedure


http://sbftech.com/index.php/topic,37479.0.html
 
#13 ·
wbrockstar has you well on your way to figuring this out. And of course there will be some fumes/smell as a byproduct of you deleting everything that was installed to combat that situation.


Take your time and run the test and check for vacuum leaks. This way you don't have to throw money at the problem hoping to figure it out.
 
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