How do I kill my wastegate?

[TJSmith]

Have you figured your problem out yet?This one has peaked my interest!

 

[Cattletrkr]

Nope, nothing yet. Haven't found the ambition. The Boost Enforcer isn't what I need... I found that out after I ordered it and tried to cancel the order... still working on that.

I'm leaning towards getting a Smarty (jr maybe) and giving that a shot. I don't want to spend the money for nothing.

I think SP's wastegate controller would work, but I want to fix the problem not the symptom if at all possible.

 

[PBrauer]

Nope, nothing yet. Haven't found the ambition. The Boost Enforcer isn't what I need... I found that out after I ordered it and tried to cancel the order... still working on that.



I'm leaning towards getting a Smarty (jr maybe) and giving that a shot. I don't want to spend the money for nothing.



I think SP's wastegate controller would work, but I want to fix the problem not the symptom if at all possible.

Cattletrkr,

I think you should try replacing the "Wastegate Command Valve", i. e. , the wastegate solenoid.

$142 at a US Cummins Dlr.

Nomenclature is tricky in Cummins parts system... they call it an "Air Control Valve (kit).

Factory Service Manual (Dodge) calls it a "Wastegate Command Valve".



Air Control Valve / Wastegate Command Valve,

Cummins PN for '06:

4036054



============

I wrote this (below) a while back but never posted it. Kinda long but it might be helpful. Couldn't figure out how to remove the "I know everthing" feeling I get when I read it myself... . I definately do not know everything.

============



Many people misunderstand how the so-called "electronic" waste gate works. . at least on late models like my '06.



The Command Valve (via the ECM) does NOT open the waste gate. The ONLY thing that opens the waste gate is actual boost pressure, PHYSICALLY applied to the diaphram. It is still a "conventional" wastegate. Boost pressure reaches the diaphram via the "Signal Line" which is that little piece of hose. The ECM uses the Command Valve to DIVERT boost pressure from the diaphram... before it ever reaches the signal line/hose. In other words, the only thing that little solenoid does/can do is to ALLOW MORE BOOST than the conventional/mechanical set point. It is actually a boost "fooler".



The waste gate also does NOT dump boost. It only reduces the development of boost by bypassing exhaust gas around the turbine. Once air reaches the compressor it has to go through a cylinder.



The following is from the '06 FSM:

{Quote}

The turbocharger features a wastegate , which regulates intake manifold air pressure and prevents over boosting at high engine speeds and loads. When the wastegate valve is closed, all of the exhaust gases flow through the turbine wheel. As the boost pressure (compressor outlet ) increases, the boost pressure is fed to the wastegate actuator via a wastegate signal line. When sufficient boost pressure is achieved, the boost pressure applied to the wastegate diaphragm overcomes spring pressure and moves an actuator rod to open an exhaust bypass valve. When exhaust gas is diverted from the turbine wheel, turbine shaft speed is limited which reduces compressor wheel speed, thereby limiting boost pressure.



The turbocharger wastegate system incorporates, an Electronically Controlled Wastegate Command Valve, to control boost pressure. The command valve is located on the turbocharger compressor housing.



When the command valve is not actuated (no current supplied to the valve), a passage in the valve allows the wastegate signal line to be supplied with boost pressure. This allows boost pressure to be mechanically regulated by the wastegate as in a conventional wastegated system.



When the engine control module (ECM) provides a pulse width modulated (PWM) signal to the command valve, boost pressure is bypassed away from the wastegate signal line through a drilling in the turbocharger compressor housing. The internal drilling bleeds boost pressure back to the turbocharger compressor inlet (low pressure). Actuating the command valve, (bypassing the boost pressure signal to the wastegate) allows the engine to operate at a higher boost than would be achieved if the wastegate were allowed to operate normally.



Actuating the command valve does not increase boost pressure if the boost pressure is below the wastegate actuator setting. With the command valve actuated, maximum boost pressure at a given operating condition will vary based on ambient atmospheric pressure and temperature.

{End Quote}



Now here's the kicker. After clamping, disconnecting, and attempting a few other things with that little piece of hose, I installed a Tee in it (signal line) and ran it to a gage on my dash. This was BEFORE I'd read the FSM. The weird thing is that, on my truck anyway, there was hardly ever any pressure on that line and even then it rarely got over 5-10 lbs. At the time I assumed those "rare" pressure readings were indications of the ECM opening the wastegate. I WAS WRONG.



When I first read the Theory in the FSM (not too long ago) I was confused, to say the least. Then it occured to me that the theory clearly states:

"Actuating the command valve does not increase boost pressure if the boost pressure is below the wastegate actuator setting. "



Almost looks like a disclaimer...

Well, my conclusion is that the ECM is constantly (almost) "allowing" boost to exceed the mechanical set point... . even though it hasn't actually exceeded it yet. When the ECM decides, for whatever reasons, that it should not "allow" the extra boost, it simply leaves the bypass closed, "allowing" the the wastegate to open "conventionally"... Clear as a bell?



Although they do state that it's a "conventional" wastegate, it wouldn't surprise me if the "setpoint" is a little low to allow a higher range of control via the ECM. The main reason for typing this is to point out that it works "exactly backwards" from the way a lot of people think it works... If the Command Valve is stuck closed, you would make normal boost until you reach the mechanical setpoint... If it is stuck open, you would set the MIL w/"Overboost"... if my assumptions and theory are correct...

 

[Cattletrkr]

That's a pretty nifty write up, but a faulty solenoid wouldn't explain why this is a winter-only problem. Yeah I would expect some droppage in boost and power, but not a drop from 40psi to 28. The boost gauge in the cab (autometer) will slam over to 25 just like always, but from there it's a major struggle. Something is limiting the boost somehow and the Juice can't override it.

 

[Grizly]

I'm not trying to be smart *** but was thinking your edge w/ attitude was doing the cold engine protection setting that will cause no fuel added til warm up/ also I have had the same thing happen to me the pump tap wire came undone soo check and make sure still conected / if the filter got bad fuel that would also do it/ I do know if more fuel you get the more boost you can get. check some of these things and see: some times it's the simple things over looked.

 

[Cattletrkr]

I have had the same thing happen to me the pump tap wire came undone soo check and make sure still conected / if the filter got bad fuel that would also do it/... some times it's the simple things over looked.

No pump tap on 3rd gens.

I have a FP gauge post filter... psi normal

Rail pressure normal

 

[PBrauer]

That's a pretty nifty write up, but a faulty solenoid wouldn't explain why this is a winter-only problem. Yeah I would expect some droppage in boost and power, but not a drop from 40psi to 28. The boost gauge in the cab (autometer) will slam over to 25 just like always, but from there it's a major struggle. Something is limiting the boost somehow and the Juice can't override it.

The solenoid is fairly exposed and also forward and below most sources of heat. If it's a little "gummed up" then the cold could definately effect it. If it's stuck closed then the gate will open at the mechanical setpoint regardless of the ECM's "allowed" boost. I'm currently leaning on 25-30 being the setpoint. I'm planning on pressurizing the diaphram manually to see when it starts turning/opening. Waiting for a dry day to reinstall my tee. Wish I'd left it in...



Right now I've got the gate locked off/closed with a pair of vise grips and some wire, tied off to a nearby bracket (not very hard to do). I'm trying to get an idea where it tends to set the overboost MIL. It never takes long (after clearing) to set the MIL but I don't think I'm learning much... too many variables and I can't get it to wait long enough to "cause" it to happen under controlled conditions. You only get one "chime". Have to re-set it each time to get any new info. Latest Flashpaq s/w allows real time monitoring of both press/temp sensors... mine are fine.



If you disconnect the signal line then the gate will theoretically never open. That would help you isolate a mechanical vs. a "control" problem. You will set the MIL soon but should make your max boost again, unless the gate is stuck open mechanically/internally. I'd heard that the ECM (stock) would start de-fueling once the MIL was set but have pretty much ruled that out in this latest round of tinkering. If I didn't mind the MIL, I'd leave everything just like it sits. I'm already planning on improvising an adjustable spring to increase the setpoint.



Not trying to be rude, but I really do think your solenoid is stuck. Mine seems to be "dragging", yours seems to be "hanging". Your symptoms really are exactly what I'd expect to see if it (solenoid) was just plain stuck closed. My opinion is that your ECM isn't opening the gate, it's failing to allow it to stay closed...



Good luck either way... if I figure out the setpoint on mine, I'll post it.

 

[Cattletrkr]

Nuts. I think I looked at the solenoid last year and it's pretty much rusted into one piece with the housing. I'll try disconnecting it and see what happens. Gonna take a few days to get it in the shop.

Thanks

 

[PBrauer]

Just had a new one in my hand the other day. Threads are wide (OD) and fairly short. Should come out OK w/some penetrant. All of the "seals" are O-rings, which surprised me, so I'm assuming they used "straight" threads. Meant to look closer but forgot. Very un-intimidating when you hold a new one in your hand.



Signal line hose clamps are "crimp" type... you can pull it off by hand and use a worm clamp to reconnect later. Fairly easy to reach the solenoid end of the hose thru the wheel well but well worth the time to remove the intake tube and work the solenoid itself from the top.



Hose is either 1/4 or 5/16 ID, I think. Might be 3/8... replaced mine with a piece of Push-Lock leftover from another project. Used those newfangled "wingnut" clamps so I wouldn't ever fight with them again.

 

[Lonestar]

Any news yet on this Cattletrkr? My 06' with the SMARTY on aftermarket turbo setting will race to 25psi, then literally hit a wall. I believe the smarty overrides the wastegate, but someone correct me if that is a false assumption.

 

[Cattletrkr]

Any news yet on this Cattletrkr? My 06' with the SMARTY on aftermarket turbo setting will race to 25psi, then literally hit a wall. I believe the smarty overrides the wastegate, but someone correct me if that is a false assumption.

Hey Lonestar!!! Long time no see.

I haven't figured it out yet. I ditched the Juice a couple weeks ago because from what I've read the Smarty is supposed to "disable" the wastegate. Mild TM for aftermarket turbo is "writing memory" as I type so I haven't had a chance to try it yet.

My problem is strictly a cold weather thing. You shouldn't have that problem down there.

 

[Gus's 03]

you guys are useing the aftermarket turbo software, corect?

that is the version that does boost fooling.







to bad is not a tripple nickle truck, you could do the #2 pencil mod. . 60 psi out of a stock turbo if ya got the fuel to do it... lol...

 

[Lonestar]

... ... .



My problem is strictly a cold weather thing. You shouldn't have that problem down there.

HEY, It was all the way down to 62* last night. I almost had to put my jeans on today instead of shorts!!:-laf



It seems to me like my WG is just opening all the time. I have enough fuel to go over 1600*, but my boost never gets over 24-25, sometimes 28



Corey

 

[Cattletrkr]

Sounds like yours is doing what mine did, but for a different reason.

I ran the Smarty on SW#5 moderate TM today. Too dang much power for me. I didn't get close to using all of it. I never towed with the Juice above level 3 (60hp). I pulled the one big hill that I run into almost daily. I can hold my speed at 60mph at ~2600rpm in 5th. Doing that a couple weeks ago with no fueling mod at all I was hitting 1300-1400* easily. Tonight at the same speed/rpm and with a fairly heavy load (37-38K gross) I think I made it all the way up to 1125*F. If I didn't see it with my own eyes I'd have an extremely hard time believing it. That puts me in the same temp range that I used to run with my '01.

I don't like driving with moderate TM so far. I have to relearn how to shift this truck as the let-off is incredibly slow. I have to completely take my foot off the accelerator a second or two before shifting. Really annoying if you're not used to it. Don't know if I'll go down to mild TM or if I'll go down to SW#3 first.

Does anybody bother with the even # SW's when running the Smarty solo?

 

[Cattletrkr]

Forgot to mention...

... but my boost never gets over 24-25, sometimes 28

Corey

... ... ... ... twins??