WGDC sometimes works...sometimes doesn't. HELP!!

Discussion of tuning specific to MAZDASPEED3/MAZDASPEED Axela/Mazda 3 MPS vehicles
Post Reply
jay32013
Posts: 7
Joined: February 28th, 2023, 10:24 am

WGDC sometimes works...sometimes doesn't. HELP!!

Post by jay32013 »

Very odd situation here - after calibrating MAF and setting up fuel and ignition tables, I've moved onto raising WGDC. Load target of 2.3 @ 5k rpm.

Initially running a Grimmspeed ECBS hooked up in 3 port config. 100% duty did not raise boost pressure at all, stuck at 102-108kpa. Tested solenoid off the car and it indeed does click like it's functioning. Attempted disassembly, clean & re-grease. Did not fix the issue.

Replaced the solenoid with a genuine MAC 3 port unit today and took the car out. Virtually no change again at 50-60wgdc.

Set the whole table to 100% and I indeed did get some results, hitting a max of 157kpa. Now I'm getting somewhere...so I thought.

Re-adjusted the table, managed to keep boost at 130ish kpa.

Now for the weird part. On my drive home, again, ZERO boost control. ECU compensating WGDC to 100% and yet I'm stuck at around 100kpa again.

Wiring to the solenoid is good, wiring loom also looks in good shape and pins are seated in the plug correctly. What on earth am I doing wrong?! :banghead :censored

I can't find a single post of people having an issue like this, so it looks like I'm alone. Could the ECU have a problem regarding circuit to the solenoid? I see no other explanation, seeing as I'm still having this issue with a new solenoid.
jay32013
Posts: 7
Joined: February 28th, 2023, 10:24 am

Re: WGDC sometimes works...sometimes doesn't. HELP!!

Post by jay32013 »

Update:

Car is throwing a P0245 wastegate A low code. Hadn’t thought to scan DTC’s previously as I got no CEL. My assumption would be this code was present with the Grimmspeed EBCS as well.

Clearing the code doesn’t help and just pops back up upon starting the car.

Getting 12v from the loom with ignition on.

Resistance is 24.8ohms across the solenoid
mituc
VersaTuner guru
Posts: 1316
Joined: December 17th, 2011, 2:47 pm
Location: Iasi/Romania

Re: WGDC sometimes works...sometimes doesn't. HELP!!

Post by mituc »

Well, if it wasn't for the last post I would have said that you have a too soft spring in the wastegate actuator or a cracked membrane.
Assuming the harness is good there is no way either a Grimmspeed or a MAC valve (basically both are the same MAC valve) would throw this code. Maybe the EBCS connector was hooked wrong/backwards?
2008 Cosmic Blue Mazda 3MPS
Built engine + WMI + GTX3071 gen2, ~509BHP @34PSI
2008 Icy Blue Mazda CX7
Stock engine and exhaust (YES!!), JBR3" + GTX2867 gen2 + Autotech HPFP, self-tuned to 330-ish BHP
jay32013
Posts: 7
Joined: February 28th, 2023, 10:24 am

Re: WGDC sometimes works...sometimes doesn't. HELP!!

Post by jay32013 »

mituc wrote: March 12th, 2023, 6:44 am Well, if it wasn't for the last post I would have said that you have a too soft spring in the wastegate actuator or a cracked membrane.
Assuming the harness is good there is no way either a Grimmspeed or a MAC valve (basically both are the same MAC valve) would throw this code. Maybe the EBCS connector was hooked wrong/backwards?
Stock spring for the gate, pressure tested and holds. Boost leak test is also spot on and holds 25psi.

I can only assume the harness is good, seeing as I’m getting 12v. Although the possibility of the ECU not grounding the solenoid could be the problem, which would suck massively :cry:

EBCS are just solenoids, so I don’t see how polarity would have any effect on operation. I‘ll check out the ECU tomorrow and verify there is no corrosion on the pins, along with doing a continuity test on the loom if I’m able to trace the wire to the ECU plug.
mituc
VersaTuner guru
Posts: 1316
Joined: December 17th, 2011, 2:47 pm
Location: Iasi/Romania

Re: WGDC sometimes works...sometimes doesn't. HELP!!

Post by mituc »

jay32013 wrote: March 12th, 2023, 9:10 am EBCS are just solenoids, so I don’t see how polarity would have any effect on operation.
EBCS are electro-valves, they may have some coils inside so feeding them inverted current may drive them in the opposite way. I've never cut one open but the safest approach is to make sure they get the right kind of current.

Also, did you notice any particularity of those moments when the EBCS is working or not? Warm engine, cold engine, and so on, things like these.
2008 Cosmic Blue Mazda 3MPS
Built engine + WMI + GTX3071 gen2, ~509BHP @34PSI
2008 Icy Blue Mazda CX7
Stock engine and exhaust (YES!!), JBR3" + GTX2867 gen2 + Autotech HPFP, self-tuned to 330-ish BHP
jay32013
Posts: 7
Joined: February 28th, 2023, 10:24 am

Re: WGDC sometimes works...sometimes doesn't. HELP!!

Post by jay32013 »

mituc wrote: March 12th, 2023, 11:09 pm
jay32013 wrote: March 12th, 2023, 9:10 am EBCS are just solenoids, so I don’t see how polarity would have any effect on operation.
EBCS are electro-valves, they may have some coils inside so feeding them inverted current may drive them in the opposite way. I've never cut one open but the safest approach is to make sure they get the right kind of current.

Also, did you notice any particularity of those moments when the EBCS is working or not? Warm engine, cold engine, and so on, things like these.
I mean I can switch polarity but doubt it’ll change, I’ve fitted lots of these solenoids and have never bothered to check. MAC also states that they can be fitted either way.

I have not noticed to be honest with you, it used to work on the grimmspeed ebcs until I changed turbo, so possibly a grounding issue.

Weather sucks at the moment so haven’t managed to do a continuity test, but I will verify that tomorrow as well as inspecting ECU pins for corrosion and so forth. Fingers crossed I can get this sorted out!!
jay32013
Posts: 7
Joined: February 28th, 2023, 10:24 am

Re: WGDC sometimes works...sometimes doesn't. HELP!!

Post by jay32013 »

Update - looks like I must have a faulty ECU. I’m getting continuity from the grounding pin of the solenoid all the way to the ECU plug, as well as constant 12v power at the plug.

Tested the solenoid again and it clicks like it’s supposed to.

Thats rather annoying :/
jay32013
Posts: 7
Joined: February 28th, 2023, 10:24 am

Re: WGDC sometimes works...sometimes doesn't. HELP!!

Post by jay32013 »

Update -

I have since opened up the factory ecu case and done a continuity test all the way to the plug at the ecu. Both 12v and ground show good continuity.

I have cleaned the ecu pins along with the plugs for the ecu. This seems to have now solved the issue, although there was no visible corrosion or debris.

I am finally able to control boost, success!
Post Reply