Disassembly: Manifold Pressure Differential Sensor

[awdonly]

You're going to need the patch to bypass the fuel tank pressure sensor. This will come in V2. If you're interested, I need a beta tester.

For now, just unplug the solenoid. It shouldn't be clicking if you have bit 15 of periphery 2 disabled though.

Currently on Chome 1.0 with the MAP mods for EVO X MAP sensor entered. Still getting constant purge clicking - Periphery 2 bit 15 (P0443, P0446, P0403, P0243, P0090, P2263) =0

[awdonly]

Doesn't matter if you're setup for Cali emissions or not. When OBD2 became standard every car had to pass the same laws statewide. All years/models had to have a purge system. The 98/99 ECU handled that system a bit differently. It my hopes this patch will still keep that function without the added sensor from the 98/99 car.

All I'd like you to test is if the solenoid works with my ROM or not. Seems to work on my car but it would be wise to confirm its functionality on a few vehicles before going public.

Happy to help.

[Greg E]

Happy to help.

Can you do a quick test for me?

Open up your ROM and set Periphery2 Bit 14 to 0.

CHANGE NOTHING ELSE and flash this to your car. Tell me if the solenoid still clicks.

If that doesn't work, leave bit 14 at 0 and switch bit 13 to 0 as well. Again, change nothing else!

[awdonly]

I'm afraid I've been playing quite a bit with the code lately - now at 1.1. Also I got a CEL P0400 (EGR) and figured out from your notes that periphery 0 bit 11 was reversed so I cahnged that back to 0 to enable EGR. While I can't swear to it - I think that was the change that stopped the clicking. I don't think Periphery2 bit 14 is the culprit as it has been at 0 for awhile since that is part of the aaronatstate setting I used.

[Greg E]

I'm afraid I've been playing quite a bit with the code lately - now at 1.1. Also I got a CEL P0400 (EGR) and figured out from your notes that periphery 0 bit 11 was reversed so I cahnged that back to 0 to enable EGR. While I can't swear to it - I think that was the change that stopped the clicking. I don't think Periphery2 bit 14 is the culprit as it has been at 0 for awhile since that is part of the aaronatstate setting I used.

Thank you!

Could you quick re-enable those periphery 2 bits (13 and 14), flash to your car and tell me what happens?

[awdonly]

OK - so now I'm confused. I enabled 2 bits (13 & 14) and clicking began within a few secnds of startup. I wasn't getting any clicking after a good 2 min of warmup (post 14) before enabling. I disabled again, reflashed, and .... clicking remains....? Is there a temperature threshold on the system? Its possible it wasn't clicking during my first test because car was cold and once it warmed up it started clicking (timing could have coincided with rom change). Now I'm really confused.

[Greg E]

OK - so now I'm confused. I enabled 2 bits (13 & 14) and clicking began within a few secnds of startup. I wasn't getting any clicking after a good 2 min of warmup (post 14) before enabling. I disabled again, reflashed, and .... clicking remains....? Is there a temperature threshold on the system? Its possible it wasn't clicking during my first test because car was cold and once it warmed up it started clicking (timing could have coincided with rom change). Now I'm really confused.

There's an intake air temperature threshold where the system is disabled below 14 degF and engine coolant temp is below 113 degF.

What's going on is since you don't have the fuel tank sensor, the ECU is seeing a constant reading of 0. This is telling the code that there's excessive vacuum in the fuel tank and it needs to open the purge to equalize the pressure.

Sit tight for a bit. I'm going to write you a patch to test.

[awdonly]

OK. Thanks. I have another EvoX MAP sensor question. In Chrome 1.1. am I correct in saying the boost guage is reporting directly on the MAP input? The reson I ask is that I have the MAP sensor hooked up to both my LCDBoostController and pin 92 of the ECU. Both report 0PSI with the engine off and substantial vac (9PSI) during idle, but the LCD BC is reporting close to 14psi of boost at WOT, while the stock boost gauge barely climbs over 7psi.

[Greg E]

Okay try this now:

CLOSE ECUFlash.
Go to C:\Program Files (x86)\OpenECU\EcuFlash\rommetadata\mitsubishi\3000 GT and open up your ROM's XML.
Open it with notepad.
Scroll all the way to the bottom and copy/paste this code before the </rom> tag.

	<table name="purge enrichment test" address="11126" type="2D" level="4" scaling="Hex16">
		<table name="X" type="Static Y Axis" elements="1">
			<data>make value = 0x0000 (stock = 0x0033)</data>
		</table>
	</table>

Save and close the file (might have to give admin permission)
Open up ECUFlash and your ROM.
Scroll down to the MISC section and locate the "purge enrichment test" table.
Change the value to "0x0000" like I instructed.
Save
Flash to car and report back.

[Greg E]

OK. Thanks. I have another EvoX MAP sensor question. In Chrome 1.1. am I correct in saying the boost guage is reporting directly on the MAP input? The reson I ask is that I have the MAP sensor hooked up to both my LCDBoostController and pin 92 of the ECU. Both report 0PSI with the engine off and substantial vac (9PSI) during idle, but the LCD BC is reporting close to 14psi of boost at WOT, while the stock boost gauge barely climbs over 7psi.

Yes

Hmm... Disconnect it from your LDCBC and tell me what happens. Worst case, I'll give you a patch to expose the boost gauge table and let you edit the values to be whatever you want.