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Discussion Starter · #1 · (Edited)
Currently testing a simple circuit prototype that allows the use of different intake manifolds on the base RSX without throwing engine codes. The circuit can be made in under an hr with a soldering iron and $11 in parts from amazon, ebay, radioshack or other electronic component retailers.

I will be logging 1k miles over the next week with the PPA manifold, and hope to switch over to a TSX manifold that I've modded for fitment (with base TB) over the weekend.

Results and a full DIY will be posted when completed/field tested. In the meantime here's a teaser image of the circuit itself:



Edit 18MAY2014:

IMRC Circuit MOD1 (based off schematic above):



TSX IM test fitting:



19MAY2014

TSX IM 80% installed:



90% installed:



20MAY2014

Test drive was a success!
I'm currently looking to source compatible plugs for the IMRC emulator for direct plug and play installation, if anyone has any tips on where to find the 2-pin solenoid plug and 3-pin IMRC sensor plug please do tell!

 

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ingenious, props to you man!!
 

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Discussion Starter · #5 ·
More info :)
The PPA manifold has 2 runner systems.

The long one runs from 0rpms-4700, then the 12v solenoid is activated to allow vacuum to change over to the short runners from 4700-fuel cutoff. During this phase shift, you notice a decrease in power and torque (butt dyno)for approx .5sec and then the power picks back up.

All great and good, as long as everything is working up to par. But along with more complicated systems, come more headaches... The IMRC system is prone to failure in all of the immediate systems: solenoid, position sensor, vacuum actuator, and valve assembly o-rings, etc. especially since these systems are getting up in age.

Repair costs vary, the DIY guy can get away with $80 at a minimum depending. On what the part required is, or up to a quote in excess of $1k to have a dealership to do the work.

I was very fortunate to get an rsx on trade for an older Acura CL due to the P1077 code being thrown. (PO did not want to pay the $800 quoted by Honda to replace the valve assembly, and lived in an area that did obd2 emissions testing)

After doing some research and connecting the dots in the helms manual, I was able to design a simple eliminator circuit using just a standard 12v relay along with a couple resisters in a dual voltage divider circuit to emulate the signal sent by the IMRC positioning sensor.

Running the eliminator circuit will allow the use of other IMs on the base ECU without throwing codes.

I will be swapping a modded RAA manifold on when I find the time, as the runner lengths are a good compromise between the high and low runners on the PPA manifold.



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Discussion Starter · #6 ·
Update: over 2k miles on IMRC delete circuit with no issues. I've yet to complete the RAA conversion or the DIY as I've been busy with a move, long work days, and a now 160 mile/day commute! Hopefully I'll be able to make some more progress after the 15th.


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So...........................

Has anyone else done this? I am trying to figure this out, got a turbo kit laying around and I have this IMRC issue. Someone please explain how to actually do this?

This is just amazing but how can a noob who has no circuit experience do this? would someone like to make one for some $?
 

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bumppp
 

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RIGHT! come back I would pay you mannn shit haaha
 

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Discussion Starter · #11 ·
After logging approx 12k on the original prototype I threw the engine codes again, but I've been so busy that I haven't had a chance to investigate until today.

Originally I suspected it was due to a failed relay since it occurred during sub-freezing temps, but upon examination, one of my wires had just come loose.

I've decided to construct the rev1 version using a prototyping PCB to make it a bit cleaner, which will also be easier to replicate for the DIYer's here.

Regarding the RAA manifold I intended to use, I've taken another look and it appears as though there may be wine interference with the PSP mount, so that's been put on the back-burner for now.

Look forward to updates on the progress over the next week.
 

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Discussion Starter · #12 ·
Made some progress this weekend.

The IMRC Delete circuit Mod1 is in full working order... I plan to micronize this circuit, weather seal it, and implement quick disconnects in the final revision.



Since I was already under the hood, I figured I'd go and check on the TSX intake (RAA) mod viability... regarding the clearance issue mentioned earlier, a little more grinding, and I believe we'll be in full working order! I hope to have this up and running later this week.

 

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Discussion Starter · #13 ·
Today's update:
Ground down the TSX IM for proper fitment, along with some light grinding on the PSP pump bracket to allow fitment with the HONDATA IMG.

Some of the lines required trimming while others required replacement with longer ones, I'm about 80% there in terms of the IM being ready for firing up. Items still to be covered:

-New evap line
-Extend MAP sensor connector (for placement on TSX IM, not on TB itself)
-EGR Delete (Black RTV & JB Weld)
-New mount for A/C line (interferes with throttle cable mount on TB)
-Short ram intake (factory TB->Airbox tube is about 1" too short with new TB position)
-Run a body ground to the IM (using HONDATA IMG sometimes requires this)

Initial Install Observations:
-IM ports are a closer match to the intake ports on the head (larger then PPA manifold)
-Easier access to items (knock sensor, starter, etc) then with PPA manifold
-All IM mounting bolts are "readily" accessible, unlike PPA manifold
-Looks "fancier?" then the black blob PPA.

 

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Discussion Starter · #14 · (Edited)
Made an evening run to the local auto store...

EGR delete plate installed.
Short ram installed (plastic fantastic.)
Evap Line installed.



Hope to be done tomorrow. Can't wait to get her off jack stands and on the road again.
 

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Discussion Starter · #15 · (Edited)
She's alive!

Observations:
-vastly improved throttle response.
-no low end gains according to butt dyno.
-high end gains are quite noticeable... Definitely worth the effort.
-appears to run a little lean @7k+ According to datalog... May swap in the TSX injectors and see if that helps.

If you're running a base IM and see above 5k frequently, the TSX intake mod is definitely worth looking into!

 

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i need help more detailed instructions of the circuit would certainly help alot, currently got the stock IM on but wanted to try your circuit before doing a swap so i made it as pictured above, and then i just tapped into the end of the two plugs from the cars harness that control the dual runner. im still getting the check engine light i tried swapping the solenoid wires 86 and 85 since the diagram doesnt show exactly which one is which.

also checked my engine harness for 5V to make sure im using the right wire for that aswell as the resistance on the delete circuit to make sure i got 30k for the ecu signal wire 87 and 13.3k for the ecu ground 87A im pretty sure in not doing something right though

car is a 06 base all wires matched your colors except for the ecu ground mine is green
 

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connected the signal wire with ground right after the the first 10kohm resistor as shown in the diagram still throws light upon start up
 

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Discussion Starter · #19 ·
BHR3: The resolution on that picture you posted is hard for me to decipher what you have going on there, but i hope this helps:

-The polarity does not matter on the solenoid wires (85 & 86)
-Difference in resistance between the relay models is insignificant in this application and should not effect circuit operation.
-You are correct on the color for the ECU ground being green, that is a mistake I made in the diagram
-Since this is a voltage divider circuit, (I think this is where your problem is:)the signal wire needs to be connected exactly as shown in the circuit. I've hand-sketched a quick block diagram that should help you figure out if you've got it wired correctly.



Bench testing your circuit:
(No Voltage applied to solenoid wires)
1: Test resistance from ECU 5v wire (30) to the SIGNAL wire lead.
-> Should read approximately 3.3k ohms
2: Test resistance from ECU 5v wire (30) to the GROUND wire lead.
-> Should read approximately 13.3k ohms

(12 volts applied to solenoid wires)
3: Test resistance from ECU 5v wire (30) to the SIGNAL wire lead.
-> Should read approximately 30k ohms
4: Test resistance from ECU 5v wire (30) to the GROUND wire lead.
-> Should read approximately 40k ohms

Hope that helps!
 
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