I havent had any issues, though like Kreionic the EGR cel is disabled. I am sure Charlie has input as well on this as he is running the same setup, but it works without problems for both of us. Have you tried disabling the EGR Cel to see if it goes away?

JB

 

I have kept the EGR cel enabled. I have had it come on about 4 times on my car and 3 times on my friend's Evo 8. I simply clear it with my $40 harbor freight reader/clearer. It is NOT a big deal and has ZERO impact on the car's driveabilty. It is a very small price to pay to be able to stealthly log boost.

when I get tired of clearing it, then I will disable the egr cel. For now, I am ok with clearing it since it does not happen often.

 

I've performed the same EGR CEL mod that JB and Kreionic have done. No CEL since.

 

Still no cel for me.

 

I think I found the table that needs to be modified to allow the EGR check to work properly with the JDM MAP sensor. I've never had the EGR CEL, and I'm on travel right now, so I need one person with an Evo IX who can easily invoke the EGR CEL to volunteer to test the fix. Please PM me, and I'll give you my email address so that you can send me your current ROM. Thanks!

 

i was just wondering.. other that for logging boost what is the benefit of changing into a jdm map sensor?

 

Cool points?

There really is no other reason. If you aren't logging boost you don't need it.

 

thanks touring buble. i'll consider this mod when i do some upgrades and start doin some self tuning.

 

I just want to check that I understand what I read throughout this thread.

In order to disable to EGR test on an Evo IX you must

Create Table

<table name="ECU Periphery2" category="Misc" address="fca" type="1D" level="1" scaling="Hex16"/>

Change Value from EFDF to 89D9

Is this correct?

 

Yes, with the clarification that the 89D9 is a hex value, so it is entered by typing 0x89D9.

 

Thanks for the clarification. I don’t want to clutter this thread up with off topic info but since you are obviously very knowledgeable, has anyone found a way to disable EVAP related CEL's?

 

Haven't looked for that sort of thing.

 

I think that the 0x89d9 will disable EVAP as well. Ask MJ, he knows for sure.

 

I guess I will just try it tonight and see as I currently have a CEL for both since they have been removed.

 

Good news. Seems that I've found the table for the EGR MAP check routine that triggers the P0401 (EGR) CEL. I went through about 1/4 tank of gas testing the fix this afternoon. I'm 99% sure that I nailed it (i.e., found the correct table to modify). I ran through the ODB-II cycle with both a high value in the table that would easily trigger the CEL and a low value that is appropriate for the JDM MAP sensor. The high value triggered the CEL both times, and with the low value, the CEL never triggered (nor was there an impending CEL code).

If anyone is interested, I was actually able to log the pressure drop as measured by the ECU when the EGR check runs. Turns out the the ECU writes the value to a RAM address, and I was able to map it to one of the MUT ports. I found that the stock USDM table value is in the middle of the range that the ECU measures when its doing the EGR check with the JDM MAP sensor. Sometimes the measurment is a little above the table value (CEL not triggered), and sometimes its a little below (CEL triggered). Any small reduction in EGR performance would consistently put the EGR measurement with the JDM MAP sensor below the stock table value (CEL consistently triggered). This would partly explain why currently some cars more readily trigger the EGR CEL than others.

I'll be posting updated instructions on EvoM sometime this weekend. As a sidenote, I found a few other tables related to the MAP sensor, one of which needs to be modified. Keep an eye out for it in the new instructions that I'll be posting.