[fasterpatrick]

Okay, I can't find this any where. Does anyone know what values I have to change to turn off the emissions on my 93 Mark VIII. EGR, EVAP, and Transmission functions are no longer needed, I have been looking everywhere to find out what I need to change but I come up with nada. I have my quaterhorse installed and all the software up and running, but I need to try to start the car this weekend and I know with all this stuff still in the system it won't run long. Please help!! and I hope to learn as much as I can so I can return the favors down the road.
Patrick

[fasterpatrick]

I guess I'm really on my own here . Can anyone offer some help as to finding out what to set the scalars at to disable all EGR functionality. unfortunately the CAZJL strategy does not contain the magical PFEHP switch used to disable the EGR strategy in every other version I can find. Also anything on EVAP disable would be nice as well.
Now I was able to start the engine and let it warm up to temp to check the thermostat and burp the cooling system but as the engine began to warm the idle would climb slowly to about 1500 rpm not good considering I set it at 750rpm.


Now it does the bump up in rpm at start and drops down to 750 and the does it's slow creep up to approx.1500 over 5min time. Any help there, I can't really do much trial time in the car yet because it's not truly roadworthy at this time but I would like to get all of the little crap in the comp taken care of so when the snow leaves and the car is ready to put on the road It's not going to run like crap.
Patrick

[decipha]

when the egr valve doesn't move the ecu is going to fault and disable it

with no transmission input the ecu is going to fault again and lock out the trans in 2nd
no biggie since you don't have it.. won't affect drive-ability

with evap disconnected i'd imagine it would do the same.. can't say for sure since i've never tuned a mod motor

[fasterpatrick]

Okay the EGR and EVAP aren't causing the run up in idle RPM. Then where should I start looking, something is behind this issue any ideas are welcome. I will put a list of possibilities together for a quick fix come spring time. In the meantime I would like to find a few others who tune the older Mark VIII and do some major brain picking.
Patrick

[bender460]

What dose it do with the IAC disconnected?

[Thunderbird6]

Following up on this thread, ( and many of the others I have read on this forum)
I have removed the EGR and EVAP. I blocked off the EGR hole on the upper manifod with a thin plate in the gasket.
I have the EGR actuator and the EGR valve bolted to the car and plugged in so the ECM thinks they are there and doesnt generate a code. THe vacuum line is also connected so the EGR valave will open and movement detected.

This all worked well for years a decade ago. Car off the road since then..

I found a thread here where a circuit diagram was offered:


Can this be verified as enough to fool ECM that these items are in place before I get into datalogging and tuning the ECM?

Also read this thread
viewtopic.php?p=102437
Recirculating Exhaust gas is not a good idea for a number of reasons, but thats for another thread...

[cgrey8]

If you have the EGR flow blocked off, but all the other EGR components in place, then the EEC will believe all is working...at least on the old Sonic EGR systems. The older Sonic systems didn't actually measure EGR flow. They assumed flow based on the EGR Valve Position. The newer systems can't be fooled like that. They actually measure the EGR flow using a Differential Pressure Feedback EGR (DPFE) sensor.

But regardless of the EGR system, if you have access to the tune, you can just as easily disable it. And if for OBD-II/emissions test reasons you don't want to shut it off, then you can modify the tune to simply not flow EGR, but still report to the OBD-II emissions computers that the system is "working."

[Thunderbird6]

Not ready to modify the ECM yet.
I have the actual EGR components connected both elctrically and vacuum. THe ECM is throwing KOEO codes of 31 82 83 85 (from memory)
31 should not be there. So I guess it is detecting that the EGR is not actually working as expected somehow.

I guess im still not sure if the resistors in the pic above will do the trick. (don care about emissions tests ever)
There are some eliminator kits that i suspect are just these resistors.
http://www.ebay.com/bhp/mustang-egr-delete
Can that be confirmed?

[ashford]

if you have the tuning capabilities you can turn off the stuff in the tune.

[decipha]

yea its as simple as

trload
tstrat
pfehp

[Thunderbird6]

OK Well looks like I need to access the tune then.
I have read a few things on the quarterhorse and so on but its hard to know what vintage the infomration is. Could you be so kind as to point me to the "how to tune the EEC IV" thread that is the current best option please.
I am also not clear if tuning will impact the ability of EEC repairers to do what they just did for me this summer ie, change out all the caps on the board and test it to see if it is working (whatever that means)

[decipha]

let me know when your ready and i'll drop a mark 8 base tune