Could it be a bad wastegate solenoid?

[QuickWE4]

Hey Guys:

This has only happened once, and I don't have any scantool data to back me up, so bear with me.

A few weeks ago, we had a break in the weather and the roads were clean so I took the WE4 out to clear the cobwebs. I was accelerating on to the highway, and I gave it probably a little more than 1/4 throttle.

I kept my foot steady - I didn't let off, but i didnt' give it any more throttle - just kept it steady. As I did this, boost came up to about 5psi, but it was almost like the boost went to 5psi and then back down to 0 and then back to 5psi and then back to 0psi - almost like I was letting back off the throttle and then hitting it again, but I wasn't. If I increased throttle, it held and the boost climbed.

Did I just hit it at the spot where the throttle blade was just not open quite enough and the wastegate was bleeding off boost? It's just strange how it did this on/off thing in rapid succession.

I haven't done any work to the car since last summer when installed my Angle Boss and powerplate. No vac leaks that I can detect. I also reset TPS and IAC when I removed the TB.

Again, this is at like 1/4 throttle holding the accelerator steady.

I know I'm describing this like a 16 year old who just bought his first TR, but again - it was not the normal boost on/boost off type of feeling....

My basic combo is a 49, Testa 100 oct chip, 009's, Big mouth cold air, thdp, usual exhaust and fuel mods, big neck IC, stock TB and plenum, RJC PP, and so forth.

Any suggestions would be appreciated -

Rich :rock:

[HairDrier]

My car would do that on the highway at about 1/4 throttle. I decided it was because my chip (Thrasher) was just a little too lean at that part of the fuel curve. Running lean will increase EGT and cause the turbo to build a little more boost. I switched to a Jay Carter chip and it went away.

If it happens again get ahold of Testa and see if he can check the fuel curve on the chip. I highly doubt you have a problem with your solenoid

[Reaper]

also you can take the WG soliniond out of the picture by looping the compessor, and letting the WG spring control the boost.

[GrndNatnl]

Thats what I'm doing at the moment. I was having boost spikes using the solenoid. Anywhere from 2 to 4 psi. So I removed the line from it and plugged it. Then I tuned the actuator rod in to compensate, however I can only get a max of 13 psi now. :( The rod is out of threads. So I'm trying to figure out what my options are now. Get a new WG solenoid, or will a HD (high boost) actuator help give me more adjustability?

The big difference that I noticed though, is that there is absolutely NO boost spike whatsoever. It only runs 13 psi, but it spools up fast, smacks 13 and stays there.

I know a lot of folks dont even run a WG solenoid, so thats what I'm looking to eliminate. Only downside is, it doesnt allow the ECM to pull boost in the occurance of detonation. Just timing. My right foot knows when to back off if the Scanmaster shows me KR anyways.

[HairDrier]

Thats what I'm doing at the moment. I was having boost spikes using the solenoid. Anywhere from 2 to 4 psi. So I removed the line from it and plugged it. Then I tuned the actuator rod in to compensate, however I can only get a max of 13 psi now. :( The rod is out of threads. So I'm trying to figure out what my options are now. Get a new WG solenoid, or will a HD (high boost) actuator help give me more adjustability?

The big difference that I noticed though, is that there is absolutely NO boost spike whatsoever. It only runs 13 psi, but it spools up fast, smacks 13 and stays there.

I know a lot of folks dont even run a WG solenoid, so thats what I'm looking to eliminate. Only downside is, it doesnt allow the ECM to pull boost in the occurance of detonation. Just timing. My right foot knows when to back off if the Scanmaster shows me KR anyways.

Sounds like your actuator is tired, or your puck is not sealing. I would not get a HD actuator, or you will not be able to go below 17-18psi. Forget about the ECM saving you in the event of detonation, once you tighten the wastegate rod to get extraboost the solenoid loses control anyways.

You can try cutting some of the rod off to allow you tighten the rod even more, but your spike may get worse then. Best to get a fresh one IMO

[GrndNatnl]

You mean if I leave the solenoid connected and adjust the rod inward it loses control?

And I'm not running the solenoid at all now. Just running off the actuator, and the rod is as far in as it will go. I can barely hang it on the swing arm. I have to pull on it a little for it to reach, then slip the retainer clip on.

Only allows 13 psi, but no spike at all. This boost is weak though, car feels slow as balls. No knock though, thats for sure.

[HairDrier]

What I am saying is the solenoid will do nothing to protect your motor in the case of detonation. The boost will just keep coming, and the knock will keep rising.

I would get a new one, especially if you think yours is stock. They dont last forever, and are not that expensive to replace. This would be a good time to pull the exhaust elbow and check to see how the puck is sealing. Also a good time to port the elbow

[QuickWE4]

Hey, thanks for the opinions guys - What I'm probably experiencing is just plain old compressor surge. When I went to this 49 and after my chip and other mods were done, the car will build boost pretty fast, but it doesn't spike as you were describing. It think the butterfly was probably closing/opening very slightly to the point where I couldn't tell the accelerator was moving and it was just surging. I noticed that when I went to the 49 and my big mouth cold air, I would get compressor surge and turbo sneeze even when accelerating which, to me, never seemed right, but I guess it's common (and even more noticeable with the cold air kits).

Well, as soon as the roads are clear of salt, it's down to Dynotech for my converter and shift kit....MWAHAHHAHAHHAHA (diabolical laughter) - turbo sneeze be damned! :pedro: I won't be able to hear it over the sound of burning rubber MWHAHAHHAHAH

Rich:wavey:

[Reaper]

with a 49 you should have no compressor surge. i would look to the wg as your offender, i have the same problem. they are right dont get an HD WG you will not be able to run less then 18psi that is an issue with pump gas...


i say get a new WG loop the compessor and you should have no issue at all!

as its been stated the WG sol. plays no role when dealing with an after market chip there is no input from the ECM. the only thing it will do is pull timing to try and save your ass :)

[TurboJim]

I have a better idea. Lets check it out, make sure there iksnt anything WRONG. Throw a scanner on it, see if it is in fact going lean or rich. See if its KR pulling timing. You do have a power plate right rich? I dont recall if you opened the egr passage. If you didnt, it coujld be knock retard as 1/4 throttle is in the "EGR" region. Eric is more than qualified to check it out Rich, or if you wanna wait till it warms up a little, swing by and we'll throw a thrashing to it and get it dialed out if it is a calibration problem.

Soon as it warms up a little, I'll be in my garage every free moment getting my turd done. I'll make time for you if you want.

[GrndNatnl]

I'm about to check all that out next week when I install the DP I have. Going to remove the elbow. What exactly should be ported? Just smooth out the lip on the exit hole? What about the entry side? (against the housing) And whats the trick for opening up the WG hole on the housing? Should I do something to keep shavings from slipping inside that hole? Everything blows out anyway, but dont want debris to get near turbine fins.

[HairDrier]

I'm about to check all that out next week when I install the DP I have. Going to remove the elbow. What exactly should be ported? Just smooth out the lip on the exit hole? What about the entry side? (against the housing) And whats the trick for opening up the WG hole on the housing? Should I do something to keep shavings from slipping inside that hole? Everything blows out anyway, but dont want debris to get near turbine fins.

Just work on the short side radius a lot, and remove any kind of lip on the entry side. You can raise the ceiling a little. Most work will be done on the short side though. Dont open up the wastegate hole unless you have a larger puck to cover it.

Took me about an hour with a dremel. Be careful if you use a die grinder that you dont take too much as they work much faster.

[GrndNatnl]

Maybe I'll find one already ported, or have someone else do one for me and observe. I'm not sure I want to risk messing it up.

[HairDrier]

Its pretty hard to mess it up. Why pay someone to do something you could do for free? I was just suggesting you use a Dremel instead of a die grinder.

[QuickWE4]

I have a better idea. Lets check it out, make sure there iksnt anything WRONG. Throw a scanner on it, see if it is in fact going lean or rich. See if its KR pulling timing. You do have a power plate right rich? I dont recall if you opened the egr passage. If you didnt, it coujld be knock retard as 1/4 throttle is in the "EGR" region. Eric is more than qualified to check it out Rich, or if you wanna wait till it warms up a little, swing by and we'll throw a thrashing to it and get it dialed out if it is a calibration problem.

Soon as it warms up a little, I'll be in my garage every free moment getting my turd done. I'll make time for you if you want.

Hey Jim -

Good to hear from you. Yep, that sounds like a plan. I will need a chip after the converter anyway. Basically just waiting for the roads to clear up and then I'm off to Eric's shop. It would be good for somebody more knowledgeable than me to road test this thing. :anbet:

I did drill out the powerplate for the EGR when I installed it. I will shoot you an email and we'll hook up one of these weekends.


Rich

[mgmshar]

Sounds like your actuator is tired, or your puck is not sealing. I would not get a HD actuator, or you will not be able to go below 17-18psi. Forget about the ECM saving you in the event of detonation, once you tighten the wastegate rod to get extraboost the solenoid loses control anyways.
Maybe I'm not understanding your point, but your statement above is not correct. The proof is in the previous statements in this thread. When somebody on this thread bypassed their solenoid by hooking up their compressor "tuner style", which is the same as turning the wastegate solenoid "off", their boost dropped to 13psi max. The boost that they lost in hooking up their compressor this way is how much control the solenoid had over their boost.

Most chips run the wastegate solenoid at a very high duty cycle, meaning they have a LOT of control over boost. Many chips also disable the feature that lowers boost when excessive detonation is encountered. That may be why there is a belief that the solenoid "loses control over boost" when the car is modified.

My car has a heavy-duty actuator. My boost goes down about 1psi for every 10% of duty cycle I take out of the wastegate solenoid pulse width in the chip. So, I have LOTS of control over boost with the wastegate solenoid.

See this link for more information...

http://www.t6p.com/forums/showthread.php?t=1196

[HairDrier]

Mike my point I wanted him to understand is that if he starts getting knock the ECM is not going to save his engine by cutting down on the boost. It will pull timing only which it will do on any setup. I did not want to get into a wastegate solenoid argument, in which it appears you are correct.

[TurboJim]

Hey Jim -

Good to hear from you. Yep, that sounds like a plan. I will need a chip after the converter anyway. Basically just waiting for the roads to clear up and then I'm off to Eric's shop. It would be good for somebody more knowledgeable than me to road test this thing. :anbet:

I did drill out the powerplate for the EGR when I installed it. I will shoot you an email and we'll hook up one of these weekends.


Rich
Converter change shouldnt need a recalibration really, I put anti-stall (small converter fix) in all my chips so that shouldnt be a problem, but if you wanna tame how it comes out of the hole a bit, we can fix it up.

Thrashed on my car yesterday awhile. I gotta bring a couple wrenches home from work to get the heater pipes and turbo drain out of the old motor, but aside from that, its just about ready to drop in. But before I do that I wanna really clean up my engine bay. What ever happened to the "detailing your engine bay" thread? Oh yea, and RS upper control arm bushings.

Oh yea, and you guys using RMI and water....my cooling system in my old motor was SEVERELY corroded. Rust, aluminum oxide....NASTY. Dont wanna discredit Nick Micale, or anything, but I suggest you guys running water/RMI check your metal components often for corrosion. I'm going back to anti-freeze.... think I'll use the Red Toyota stuff which is silicate free and wont congeal like Dexcool. Just a FWIW.....

[TurboJim]

Mike my point I wanted him to understand is that if he starts getting knock the ECM is not going to save his engine by cutting down on the boost. It will pull timing only which it will do on any setup. I did not want to get into a wastegate solenoid argument, in which it appears you are correct.
Actually, there is a max retard before lowering boost DC parameter in the chip. I dont change it as its rarely a problem and I believe the stock cal starts lowering DC at 15* KR and theres a threshold of how MUCH to remove. But I dont think its KR he's seeing if his EGR passage is open. I'd say more that he's on the bottom of the compressor map and the exhaust is flowing enough to get the turbo to start spinning, then its not enough to keep it accelerating so it slows a bit, then it overshoots the exh flow and the exh flow brings it back up etc... the wastegate shouldnt even be in the pic at 1/4 throttle, what could he see, 10psi? My car has slight surge barely accelerating up an incline. I'm like JUST at the point where exh flow is speeding up the turbo, then it overshoots, exhaust flow isnt sufficient to keep the wheel accelerating and the weight of it inertia wize keeps it accelerating for a sec, then it begins to slow until exh flow is sufficient to speed it up again and this cycle keeps repeating till I 1) let off 2) get on it a tad more and it goes away.

Just my opinion....

[HairDrier]

Oh yea, and you guys using RMI and water....my cooling system in my old motor was SEVERELY corroded. Rust, aluminum oxide....NASTY. Dont wanna discredit Nick Micale, or anything, but I suggest you guys running water/RMI check your metal components often for corrosion.

Did you use RMI year round or do you switch to antifreeze in the winter? Were all the coolant passages corroded or just the radiator? How many years had you been runing RMI?

[TurboJim]

Did you use RMI year round or do you switch to antifreeze in the winter? Were all the coolant passages corroded or just the radiator? How many years had you been runing RMI?
Well, the car has sat for the better part of the last year. When I took the motor out and started disassembling, I noticed a lot of aluminum corrosion. I wrote it off as the car sitting. Then as I started taking out the thermostat housing, tstat, heater pipes etc, there just seemed to be a LOT more rust/corrosion than I thought there should be. I assumed since theree is no real corrosion inhibitor in water (I didnt look at the RMI bottle) that its due to the fact coolant wasnt being used.

I'm not saying RMI is the problem, I am saying that its very possible, that using WATER and no corrosion inhibitor may wind up being more of a problem than was thought.

Again, I'm going back to regular ole coolant, just wanted to give a heads up in case any other guys are getting into their motor and noticed this.

[HairDrier]

From the bottle:

"RMI-25 is used in new vehicles to prevent corrosion and in used vehicles to clean the system and prevent corrosion" :add_shit:

Doesnt sound like it prevented much for you. Did you use distilled water or tap water?

I will continue to use it because my radiator sucks and it drops my temps by 10-15 degrees. But that pisses me off that it didnt do much to protect your engine