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waste gate actuator adjustment for turbo charged optima power loss problem

223K views 181 replies 67 participants last post by  KingFatty 
#1 ·
So if your like me and would rather die fixing your car than taking it back to the dealer, only to have them fail at another simple task. Then here is the fix for the turbo charger "loss of power/ restart the car everything is fine" problem everyone is bringing in their car for. I started experiencing the problem around 9,000 miles and read over the entire TSB about how they adjust the wastegate to 4.2V to make it shut sooner. But I dont have a OBD scanner or software to read the voltage on the waste gate. I do however have 10 years electronics troubleshooting experience and knew that it was reading a feedback position voltage that was coming from the electronic motor that controls the waste gate. The problem was which wire was it? Well after doing some slick piggybacking on each wire with the connector plugged it I have the answer. If you look at the connector you take off of the motor it is the yellow wire on the connector. If you piggyback off that wire while the connector is plugged in and the car is on (engine not started but radio and everything on)you will see a voltage of around 4-4.7 VDC using the battery ground as ground. As you move the waste gate rod by hand to the left (passenger side) you'll see it decrease toward 0VDC. What you want to do is pull it all the way to the right (driver side) and read the voltage. mine was actually at 4.6 VDC! So if its above 4.3 VDC you have to shorten the rod. Take the bolt off the top of the rear cover on the turbo to make room so you can move it as you need. Take the clip off of the turbo charger side (BE CAREFUL NOT TO LOSE IT!) it is a C clip with a small loop u can hook something around to pull it up and off. And there is a small washer on the other side of rod so take care not to lose that too when you take the rod off. The motor actuator side is a small locknut that i believe is 10mm. you take that nut off and the whole bar should come right off. Loosen a locknut on whichever side shows the most threads and turn it clockwise if its above 4.3VDC (making the bar shorter) and counter clockwise if its below 4.1VDC(making the bar longer). Then make a turn or two adjustment and without locking the nuts down yet put the bar back on the wastegate connection and motor connection and once again push the rod by hand all the way to the right (driver side) repeat this process until your meter reads 4.2VDC (+/- .1VDC) with you pushing the electronic wastegate actuator all the way to the right. once you achieve this lock down the locknuts on the rod and reinstall the rod reverse of removal (IMPORTANT TIP!!!!! tie a small piece of string around the small loop on the C clip when you go to put it back on as if you drop it you will spend 2 hrs like i did looking for it in your engine!!!!!) I hope this helps. I just did it to my car and shes a COMPLETELY different beast as if your voltage was over 4.3VDC it wasnt putting as much closing force on the wastegate as it should, letting exhaust gas slide on by. I would like to take it back to the dealership but after they put 5w-20 in my car when EVEN THE CAP says 5w-30 i have less than no faith in them anymore...
 
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#13 · (Edited)
Its VERY useful pics or not. You can't get a camera here you need to see at. the connecting points for the bar face the firewall. You need a mirror to see the clip.

My dealer had my car from 9am-2:30PM trying to fix this one issue( and a simple oil change. They wanted to put in 5W-20 bc the service writer did not know EX-Turbos existed.) It was reading 4.8V. When i left at 2:45PM my voltage was 4.8V. The mechanic claimed that he was unable to make the change bc the temp of the ambient air was to hot. I call bullshit. How can ambient air affect voltage. Needless to say i will be tackling this repair myself. Thanks for the write up.
This is EXACTLY why i usually try to avoid the dealer at all costs! That voltage has NOTHING to do with air temperature. There is a variable resistive device in the motor that changes that voltage going to the yellow wire as the motor moves. The computer then reads the voltage to determine what the position the waste gate is in. around being 0 is completely open and 4.2 being completely closed. Temperature effects this in no way as it measures movement of the waste gate actuator only. I hate incompetent mechanics, but what i hate more is someone who feeds some bullshit to someone because they themselves dont know whats wrong.. Just say i dont know!
 
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#7 ·
My dealer had my car from 9am-2:30PM trying to fix this one issue( and a simple oil change. They wanted to put in 5W-20 bc the service writer did not know EX-Turbos existed.) It was reading 4.8V. When i left at 2:45PM my voltage was 4.8V. The mechanic claimed that he was unable to make the change bc the temp of the ambient air was to hot. I call bullshit. How can ambient air affect voltage. Needless to say i will be tackling this repair myself. Thanks for the write up.
 
#181 ·
My dealer had my car from 9am-2:30PM trying to fix this one issue( and a simple oil change. They wanted to put in 5W-20 bc the service writer did not know EX-Turbos existed.) It was reading 4.8V. When i left at 2:45PM my voltage was 4.8V. The mechanic claimed that he was unable to make the change bc the temp of the ambient air was to hot. I call bullshit. How can ambient air affect voltage. Needless to say i will be tackling this repair myself. Thanks for the write up.
If it’s a resistor, the ambient will make a difference. The adjustment is supposed to be done cold.
 
#8 ·
Syn,

Amazing DIY. I appreciate your writeup, particularly with wiring investigation to find the correct point to read this voltage. Your description seems quite accurate and thorough, and the caution comments are really valuable. The combination of this DIY and ultracow's lubrication suggestion go a long way to solving this problem.
 
#14 · (Edited)
I have never seen someone get so butthurt over an emot. Wow, hostile much?
Why would you assume that I think this is useless? This is great information. People should know how to fix their own problems with their own car. I also hate taking my car to the dealership.
Pictures always speak louder then words.
I will eventually get my volt meter out and test my own.
 
#17 ·
Syn, I think NiMrod just wanted pictures to make sure that he does it correctly when the time comes and the pics would help other memebers as well...as I wanted a VID...(I think you just took it the wrong way) :)

We all found your post enlightening...When the time comes, I'll be doing this myself also, Thanks!
 
#18 · (Edited)
All credit to Syn! His instructions were very easy to understand and follow. But I figured since I was there, I would snap a few pictures as I checked my voltage:

First, here's a wide angle shot of the motor Syn is refering to, so you can kind of get your bearings. This is with me standing near the drivers front tire looking into the engine bay






Now, to clear up what motor Syn is talking about, here is a closer shot. The motor should be the focal point.




Next I uncoupled the plug on the top of the motor (as seen in the picture above) by pushing it towards the front of the car. Then I carefully pushed a thin sewing needle down along the yellow wire into the back of the plug. Then I plugged the plug back in, hooked one end of an alligator clip extension to the needle and the other to my positive multimeter probe. Then negative went to the car battery. I leaned in the window, hit my start button twice and voltage started being read. I pushed the rod towards the passenger side (0.51v) and then towards the drivers side. My reading was 4.07v. I leaned in and turned the car off. Then I took just the motor end of the rod off and twisted the rod out half a turn. I remeasured and the reading was 4.27 volts, so that was where I left it. Better to be barely in spec than barely out I reasoned.







I did not loosen the turbo half of the rod at all. I found it was plenty easy to loosen just the motor connection and blindly adjust. BE CAREFUL. As said by Syn, after the locknut on the motor end of the shaft is the rod itself, then a washer/seat piece and a spring. I managed to lose my spring doing this because while I thought I was being careful, I wasn't careful enough apparently. I also dropped a 10mm wrench down there somewhere. :angry: I guess I'll be pulling the motor shield off this weekend in hopes of finding both items.


Heat shield mentioned in the OP (the left one of the two):

 
#22 ·
Thank you for adding pictures to this. As for the needle you poke It into the yellow wire and then connect the red lead to that to read the voltage as the connector must be plugged in and the car on to read the voltage. It's sad Kia techs didn't even know how to do this. And the tsb is meant for them to understand and do. Haven't had the problem once since I've done this. Car is so much more powerful now.
 
#24 ·
Lower,
That spring and washer you talked about on the motor side. I don't remember seeing that on mine. Either I lost it or didn't have it. I went on kgis and it doesn't show it In The component breakdown. It makes mention not to lose the washer on the turbo side but nothing about the spring and washer...
 
#27 · (Edited)
Huh, strange.
When it was on the motor, it looked like a stack of washers, because the spring was compressed. You can see them here;









They look like this off the motor;





Yes, the needle is for getting signal off the yellow wire without hurting the wire. The back side of the plug, where the wires enter has some dense foam material on it to keep water out of the connection. Pushing a needle down the wire allowed me to follow the yellow wire down into the plug far enough to touch the metal connector of the plug from the backside. Then needle to alligator clip to positive probe, and negative probe to car battery. Simple really.
 
#30 ·
Lower,
Called a good dealership( with actual knowledgeable techs, unlike mine) and found out why yours has a sprig and mine didn't. It is for the waste gate rattle problem people were having. It's comes standard on 2012 and beyond but on the 2011 there is no spring and washer on that side unless it was brought in for this problem. I was scared I lost it for a sec
 
#38 ·
Lower,
Called a good dealership( with actual knowledgeable techs, unlike mine) and found out why yours has a sprig and mine didn't. It is for the waste gate rattle problem people were having. It's comes standard on 2012 and beyond but on the 2011 there is no spring and washer on that side unless it was brought in for this problem.
Wait, mine is a 2012 and it rattles like crazy.......so are we saying there is a fix for the rattle???
 
#31 ·
Uh, so people with gate rattle issues now have a known fix? ! ? !

If so, you my friends have solved double the issues! Great job!


As for performance differences, I would say for me, little to none. But I went from 4.07 (.03 out of spec) to 4.29 (in spec by .01) or another way to look at it, I went from .13 from the perfect measure of 4.2 to being .09 from it. not a big change.

It was interesting to see what mine was set at though. And if yours is off by a big amount, I have no doubt this will change things for you.
 
#32 · (Edited)
Sooooo never thought to check "Component" section of KGIS, but yea...all this is in there. I converted it to PDF and will host the file through my GMAIL.

Heres exactly the instructions the techs see, color 3D models and all
: https://docs.google.com/open?id=0B2A8Ma05-ZRmb1lLOC1idFhTWmc

Also Syn (and all),
note in the PDF that mechanical close should equal 4.8V.. I noticed you measured 4.8 with your hand closing it, that was correct! Its 4.2V with the motor closing it, 4.8V hand force pushing/closing.
 
#37 ·
note in the PDF that mechanical close should equal 4.8V.. I noticed you measured 4.8 with your hand closing it, that was correct! Its 4.2V with the motor closing it, 4.8V hand force pushing/closing.
I believe the 4.8 is in reference to the fully closed position the rod would be in with the rod disconnected. In other words, the 4.2 is the voltage the motor sees when the waste gate hits maximum, but the motor (if unconnected) might still have travel left. I hope this makes sense, because after playing with it by hand I just don't see how I could be pushing it any further than the motor would be. Although I do recall that the motor traveled past where the maximum was for the waste gate closure. I'm not mechanic by any means - but this would be the only way the 4.8v "by hand" would make sense to me.
 
#33 ·
The only people who will notice a big change are those over 4.3vdc because any higher the motor hits it's mechanical stop before the waste gate does which means it isn't completely sealing so the turbo isnt spinning to its full potential. Although if it's under 4.1 that mean its not open as far as it should be when you hit max pressure on the turbo. That's how it regulates its speed and doesn't spin into infinity creating more than 17 psi. I wonder if people who are under 4.1 how much pressure they read. In theory it should regulate slightly higher since the waste gate doesn't open as far as it should.


But yes they told me on the phone the spring and wAsher are for the waste gate rattle proble
 
#34 ·
Wow! Great thread!

Question: What are the symptoms of this problem to start with?
 
#35 ·
Question: What are the symptoms of this problem to start with?
I, and a lot of others, developed an intermittent CEL-less limp/half-power mode.

The dealer adjusted mine from from 4.59 to 4.09 in June, but I've noticed something feeling off with acceleration over the last couple weeks. The service writer told me he'd seen cars pull themselves back out of spec after being fixed, so I've been worried it's coming back.

I did the Blaster lube thing last weekend, but that won't fix an arm that's already slipped out of adjustment, so this thread is perfect timing.
 
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