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Help diagnosing cyclone manifold problem.

cupajoe

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Mar 1, 2010
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343
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Cocoa, FL
Okay, I'll start with this. I have it setup like this image, I'm using Link to activate through the FPS controls.

Link setup is: start at 1500rpms and stop at 2500rpms for testing. Everthing else is zero'd out.

When I start the car the diaphragm closes the valves so I know it has vacuum, but it won't open when I reach 1500 rpms. Link is showing the FPS is engaging from "0" to "1" when reaching the threshold. Yes, I verified I have the FPS hooked up to the correct plug. Out of curiosity I went ahead and checked the volts coming from the plug and it gets a constant 12v regardless of if I meet the threshold or not. If I'm not mistaking that would mean its staying open the whole time which is not what I want. Can someone verify this for me by either checking your volts at the plug?

Side note: what could cause the plug to get a constant 12v? Is there another way I could take control over say the EVAP/EGR plug through link?
 

cheekychimp

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Apr 19, 2004
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Joe, are you still having issues?

I started writing a reply which was essentially wrong so stopped but the more I think about it, the more I think your issue 'may' be related. The reason why my first response was wrong is because I failed to understand that the Link nitrous controls directly interface with your tach signal. I was suggesting that you still needed an rpm switch to activate your solenoid between the relevant thresholds. That is wrong, but one thing I thought that I remembered from that how-to was that the fuel pressure solenoid was in effect always powered but that it was the rpm switch that essentially activated the cyclone when it reached the set rpm point. I believe this is achieved by diverting air from the bottom to the top port.

So I'm leaning towards the theory that there is a problem with the tach signal not getting to your FPS to activate the port change or that alternatively the FPS is not functioning properly. I am not sure if the FPS receiving a constant 12 volts is necessarily an indication of a problem on the stock wiring loom. Surely the FPS comes on with the ignition?

One other thing. I can't find anything on the web to confirm this, but I'm pretty sure that the vacuum canister being a one way valve has to be connected in the correct direction. This won't affect your volts but I have a feeling that having it hooked up the wrong way leads to the butterflies being stuck fully open or fully closed (can't remember which). I'm sure you haven't done this but it was just a thought. Sometimes we get wrapped up in complicated things we assume are the problem and miss something stupid.

If these aren't the issues, post up and let's keep working on this, but this one has me stumped so far.
 
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cupajoe

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Cocoa, FL
Yeah, still doing the run around with this.

What I have figured out so far is that there will in fact be 12v constant going to the FPS. When the rpm threshold is met, the ECU side wire will pull it to ground and activate the FPS. My next issue is I'm not sure how to test to see if it gets grounded. If I could confirm that then I can narrow it down to a faulty FPS.

What else do you think I'd have to check? Why wouldn't it be getting a tach read out?

You are in fact correct, hooking up the canister is different orientations will either leave the valves stuck in open or closed. I do have it set in the right direction, because when I start the car it see's vacuum and closes the valves.

I appreciate the help, hopefully I can figure this out soon. Only thing keeping me from turning W/M injection on and doing my final tune.
 

prove_it

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Jul 3, 2008
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Sioux Falls, SD
Disconnect the solenoid and check resistance to ground on the ground wire at the solenoid connector. Run the car to the rpm point and see if you go from infinite(open) to near 0 ohms resistance. This will tell you if the ground side of the wiring is functional, also verifies the ECU is ok.

At that point I would say the solenoid is bad. You can also test the solenoid by applying power and ground to it on a bench, verify it's good.
 

cupajoe

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Mar 1, 2010
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Cocoa, FL
^ Thanks, got this a little late but I believe I got the same answer. I put a test light to the ground and to the power side of the battery, no light at the set RPM. Also put a fluke meter on the ground/power of the plug and rev'd it up to the rpm and didn't get 12v.

Also, to verify the light worked I did the same test to the EGR plug and it got a light. So the sensor looks like it is in fact working, but for whatever reason I have nothing going to the FPS. I even went ahead and set the FPS to stock and still no light or volts to both sides.

Whats my next step?
 

cupajoe

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Mar 1, 2010
Messages
343
Location
Cocoa, FL
If I can't figure out why I don't have control over the FPS wiring, I might just have to use an RPM switch. The last thing I wanted to do was hack up some more wiring and make a mess.

Here is a link. Its option two.

click
 

belize1334

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Nov 18, 2003
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3,316
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Bozeman, MT
Are you sure you're using the right part of the harness? Maybe you're testing the purse solenoid, which ECMLink doesn't control.
 

cupajoe

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Mar 1, 2010
Messages
343
Location
Cocoa, FL
I'm fairly certain I am using the correct harness. Correct me if I'm wrong, it's coming out of the loom with the BCS plug and has this color scheme on the wires.


img.php
 

cupajoe

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Mar 1, 2010
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Cocoa, FL
cheekychimp, I think you are on the right track about the tach signal. What would cause a lack of signal or where would I start?
 

prove_it

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Jul 3, 2008
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Sioux Falls, SD
If your commanding the solenoid via link, you can check your tach signal by datalogging the rpms. Unless I'm wrong, but I'm not aware of two tach signals.
 

cheekychimp

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Quoting cupajoe:
cheekychimp, I think you are on the right track about the tach signal. What would cause a lack of signal or where would I start?



To be honest I'm not sure. My biggest problem here if I am brutally honest is that I don't fully understand the correlation between the tach signal and the FPS in the stock harness setup. Is it just set up to increase fuel flow with rpms? I can't really see that, with all the more important information like IDC that could be used, but maybe simple works. Is there any possibility the tach signal is already being intercepted somewhere (like a shift light) so that the manifold isn't getting the signal because the previous threshold hasn't yet been met? Shot in the dark but I can't really see why a) if the FPS needs an rpm signal to work it is still performing it's primary function and b) how tapping into the signal wire rather than cutting it would stop the FPS seeing the right reading.

You mentioned that you have the vacuum canister working correctly because it pulls the valves closed when it sees vacuum at idle. Presumably that means that without vacuum the butterflies spring open? If the valves are operating correctly then it could possibly suggest there is a problem with the vacuum lines or ports. Is there any way to verify that the FPS is diverting air properly by grounding it and changing the flow of air? If you can do that then it verifies the solenoid is working correctly and it almost definitely suggests that it just isn't seeing the rpm signal or the signal is failing to ground the FPS as required.
 
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GSTwithPSI

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I think it would be helpful if you took a screenshot, or posted up a log so I can see exactly how you have the activation conditions set up under the FPS tab. I know you said ECMlink is showing 0 to 1 which would indicate the ECU is trying to engage the solenoid, but it wouldn't hurt for someone to double check your settings I suppose.

My first suggestion would be to swap the FPS over to the EGR plug (I'm pretty sure it's the same plug). Mirror your settings from the FPS tab to the EGR tab and see what happens. If you get the exact same results, I'd say there is some external factor at play (solenoid, vacuum setup, etc).

I struggled with the ECMlink boost control for almost 2 weeks before I found out it was a problem with my ECMlink configuration. I feel your pain...
 

cupajoe

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Mar 1, 2010
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343
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Cocoa, FL
Quoting cheekychimp:
Quoting cupajoe:
cheekychimp, I think you are on the right track about the tach signal. What would cause a lack of signal or where would I start?



To be honest I'm not sure. My biggest problem here if I am brutally honest is that I don't fully understand the correlation between the tach signal and the FPS in the stock harness setup. Is it just set up to increase fuel flow with rpms? I can't really see that, with all the more important information like IDC that could be used, but maybe simple works. Is there any possibility the tach signal is already being intercepted somewhere (like a shift light) so that the manifold isn't getting the signal because the previous threshold hasn't yet been met? Shot in the dark but I can't really see why a) if the FPS needs an rpm signal to work it is still performing it's primary function and b) how tapping into the signal wire rather than cutting it would stop the FPS seeing the right reading.

You mentioned that you have the vacuum canister working correctly because it pulls the valves closed when it sees vacuum at idle. Presumably that means that without vacuum the butterflies spring open? If the valves are operating correctly then it could possibly suggest there is a problem with the vacuum lines or ports. Is there any way to verify that the FPS is diverting air properly by grounding it and changing the flow of air. If you can do that then it verifies the solenoid is working correctly and it almost definitely suggests that it just isn't seeing the rpm signal or the signal is failing to ground the FPS as required.



I'd have to agree with you, in stock configuration the FPS does NOT use the tach signal and most likely uses something else along the lines of ECT and maybe another parameter. But with that said once you take control over the sensor that's when it would be controlled by rpm through link. The FPS does in fact work, when I plugged it into the EGR plug it opened and closed the valves like it should, but I have no control over the EGR and unfortunelty I have my wideband hooked up through that pinout on the ECU for link.
 

cupajoe

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Mar 1, 2010
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Cocoa, FL
Quoting GSTwithPSI:
I think it would be helpful if you took a screenshot, or posted up a log so I can see exactly how you have the activation conditions set up under the FPS tab. I know you said ECMlink is showing 0 to 1 which would indicate the ECU is trying to engage the solenoid, but it wouldn't hurt for someone to double check your settings I suppose.

My first suggestion would be to swap the FPS over to the EGR plug (I'm pretty sure it's the same plug). Mirror your settings from the FPS tab to the EGR tab and see what happens. If you get the exact same results, I'd say there is some external factor at play (solenoid, vacuum setup, etc).

I struggled with the ECMlink boost control for almost 2 weeks before I found out it was a problem with my ECMlink configuration. I feel your pain...



Where is the page in link for EGR settings? Might give it a shot, but unfortunately I can't use that because my wideband is setup through that pinout. Looks like I don't have the EGR tab because I'm still using V2, but I'll grabe a screenshot for you to double check.
 

tektic

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Dec 19, 2012
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ronkonkoma, ny
wide band is usually connected to the egr temp sensor wire. the pin needs to be added to a galant. Thats the only unused 5v input to the ecu. At least the federal dsm ecu.
 

swe_gvr4_1991

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Jul 27, 2006
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177
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Sweden, Alingsås
The FPR conditions are only dictated by IAT and ECT values. It does not get any orders from the VSS.
On the other hand, the VSS dictates conditions for various other stuff so a working VSS is crucial. (If not disabled or emulated thru code.)
For instance the fuel trims, ISC, and ODB code routine.

Hope this helps.
 
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GSTwithPSI

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Quoting cupajoe:
Quoting GSTwithPSI:
I think it would be helpful if you took a screenshot, or posted up a log so I can see exactly how you have the activation conditions set up under the FPS tab. I know you said ECMlink is showing 0 to 1 which would indicate the ECU is trying to engage the solenoid, but it wouldn't hurt for someone to double check your settings I suppose.

My first suggestion would be to swap the FPS over to the EGR plug (I'm pretty sure it's the same plug). Mirror your settings from the FPS tab to the EGR tab and see what happens. If you get the exact same results, I'd say there is some external factor at play (solenoid, vacuum setup, etc).

I struggled with the ECMlink boost control for almost 2 weeks before I found out it was a problem with my ECMlink configuration. I feel your pain...



Where is the page in link for EGR settings? Might give it a shot, but unfortunately I can't use that because my wideband is setup through that pinout. Looks like I don't have the EGR tab because I'm still using V2, but I'll grabe a screenshot for you to double check.



Ah, I didn't realize you were using V2. The tabs I'm referring to exist only in V3.

But, after doing a little reading, I have a few things for you to check. As I said before, it would really help to see a screenshot of you nitrous control - FPS solenoid tab. I'm assuming you have the box checked that says "enable nitrous control".

Two other things you need to verify are the clutch switch and rev limit. The nitrous controls are deactivated when the clutch switch is activated (clutch in), and also if ANY of the rev limits are reached. Verify those two things aren't hindering operation.

That screenshot would really help here...

Link V2.5

Edit: Another thought, if you activate the FPS manually using Link, does it click? To activate the FPS manually, you have to disable nitrous controls and enable normal FPS operation. Try to activate it manually and see if it works. That would actually tell you a lot.
 
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cupajoe

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Mar 1, 2010
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Cocoa, FL
Great idea on just activating the FPS. I went ahead and did this and still didn't activate the FPS, also hooked up the volt meter and still didn't ground it out. Figured I Ohm out the ground wire from the fps plug to ECU, results were 00.3-00.6 ohms. Can someone tell me if that ground is good or bad? Clutch switch is disabled and rev limit is set to 8k.


Here is a picture of the settings, I tried both checking and un-checking the Factory settings and still to no avail.
 

GSTwithPSI

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00.3-00.6 ohms should be ok. Just to double check, you went from pin 7 on the ECU to the white wire on the FPS connector plug to check the ground side, correct? Also, check the red wire on the FPS plug for 12v with the ignition switch in the run position. The FPS gets 12v from the MFI relay anytime the ignition switch is in the ON position.

If the ground to the ECU is good, and you have 12v at the FPS plug with the car on, then you may want to consider trying another FPS solenoid. You should definitely be able to activate the FPS manually with Link. I'm leaning toward a bad solenoid, or a wiring issue. From what I can see in the screenshot, your config appears to be fine.
 
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cupajoe

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Mar 1, 2010
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Cocoa, FL
You mean pin 57? to the white one on the plug? That's what I tested. I do in fact gave 12 volts and 13.xx when the car is running coming from the power wire for the FPS. I then hooked up the fluke to both ground and power wire on the plug to see if I get fluctuation when I activate the fps and I did not. Which doesn't makes sense, Ecu is showing it engaging and disengaging, ground wire is good, power wire is getting 12v. I'm baffled. Also to check if the solenoid worked I hooked it up to another plug on the passenger firewall (EGR?) and when I bring the rev up it vents the air and when it drops to idle it'll close the valves again.

This is the correct plug right?

 
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