The 3.4L TRD Supercharger Thread

[shootmymime]

Wouldn't the knock sensor help with this situation? I mean I'm not getting any dash lights or error codes.

Unless my knock sensor is bad.

Description of a knock sensor on our vehicles if you dont fully understand them yet-


our truck under NA conditions run great, the reliability and efficiency they run at are quite well. The ECU reads from all sorts of sensors (including the knock) and makes adjustments so that the vehicle sits on the fence between the best efficiency it can achieve without causing harm. - that is where the knock sensors come in. the knock sensors help the motor notice knock and retard the engine timing. but sometimes the adjustment the motor needs, is out of the range that the ECU can actually reach.
it mainly has to do with timing and fuel with boosted applications like we are talking about.

when we add boost, the ECU tries to get the vehicle back into spec by making adjustments. But sometimes the vehicle is not able to make large enough adjustments to completely compensate for the added boost (this is where toyota is lying when they said trd supercharger is a pure bolt on system.)

generally we need more timing taken out (retard the timing) to account for this extra pressure in the engine and sometimes more fuel.

When the engine creates boost via supercharger, the vehicle generally can not spray enough fuel into the engine, thus the engine temp rises drastically. When temps rise, more timing needs to be taken out, as well as fuel needs to be added.

 

[MTD]

Apparently my post didn't go through, but what he said ^^

 

[shootmymime]

Apparently my post didn't go through, but what he said ^^

Yeah yeah yeah. Trying to steal my thunder. -jokes.

 

[MTD]

Yeah yeah yeah. Trying to steal my thunder. -jokes.

haha all mine said is that the ECU didnt have enough room to correct for the amount of knock, you win sir lol:fencing:

 

[SCRunner12]

[MENTION=71420]masphx[/MENTION] can you take a video of you turning the shaft with the pulley off? These viton seals are very tight when you first install them and do provide a good amount of resistance. You can try getting some oil between the seal and shaft to loosen it up. Many guys soak the seal in oil prior to installation to loosen it up and allow it to form fit.

 

[masphx]

[MENTION=71420]masphx[/MENTION] can you take a video of you turning the shaft with the pulley off? These viton seals are very tight when you first install them and do provide a good amount of resistance. You can try getting some oil between the seal and shaft to loosen it up. Many guys soak the seal in oil prior to installation to loosen it up and allow it to form fit.

When I have pully pulled forward just tad it does not bind anymore and the supercharger feels like it spins fine. I think the pully is setting in further then it should thus rubbing on the housing causing the binding.

 

[la79]

Description of a knock sensor on our vehicles if you dont fully understand them yet-


our truck under NA conditions run great, the reliability and efficiency they run at are quite well. The ECU reads from all sorts of sensors (including the knock) and makes adjustments so that the vehicle sits on the fence between the best efficiency it can achieve without causing harm. - that is where the knock sensors come in. the knock sensors help the motor notice knock and retard the engine timing. but sometimes the adjustment the motor needs, is out of the range that the ECU can actually reach.
it mainly has to do with timing and fuel with boosted applications like we are talking about.

when we add boost, the ECU tries to get the vehicle back into spec by making adjustments. But sometimes the vehicle is not able to make large enough adjustments to completely compensate for the added boost (this is where toyota is lying when they said trd supercharger is a pure bolt on system.)

generally we need more timing taken out (retard the timing) to account for this extra pressure in the engine and sometimes more fuel.

When the engine creates boost via supercharger, the vehicle generally can not spray enough fuel into the engine, thus the engine temp rises drastically. When temps rise, more timing needs to be taken out, as well as fuel needs to be added.

Really great explanation of things. Puts it in context.

 

[4Reak Show]

I am under the impression that the knock sensor is ignored until the engine is about 3000 RPM or higher as well.

And for the record I did have pretty bad ping in my rig prior to 7th and it would always happens, regardless of any other variable such as temp or time driving, in the 2-3K range at half throttle or so especially in 3rd and 4th gear. After it got above 3k the ECU would detect it and was able to compensate, also because it's spinning faster it's normally planning to have the timing advanced so it's correctable range is more broad in higher RPM.

That's my story and I'm sticking to it! Either way, all that's gone with a little extra fuel and a little more timing retard.

 

[MTD]

And for the record I did have pretty bad ping in my rig prior to 7th and it would always happens, regardless of any other variable such as temp or time driving, in the 2-3K range at half throttle or so especially in 3rd and 4th gear.

You can avoid it though if you don't load it up in those ranges. If I was going to boost I would always wind it out a bit and I never had an issue with ping.

 

[shootmymime]

I am under the impression that the knock sensor is ignored until the engine is about 3000 RPM or higher as well.

And for the record I did have pretty bad ping in my rig prior to 7th and it would always happens, regardless of any other variable such as temp or time driving, in the 2-3K range at half throttle or so especially in 3rd and 4th gear. After it got above 3k the ECU would detect it and was able to compensate, also because it's spinning faster it's normally planning to have the timing advanced so it's correctable range is more broad in higher RPM.

That's my story and I'm sticking to it! Either way, all that's gone with a little extra fuel and a little more timing retard.

isnt the knock sensor disabled in open loop? hence its called open loop? so i believe your mixed up on when the knock sensor is being read.

- you do live in California that has crappy fuel and so low to sea level.

 

[4Reak Show]

Ya in open loop the ECU pretty much only looks at CKP, CMP,MAF AND TPS. Ignores the O2 is the important part. However, I'm also under the impression open loop only occurs when cold, and when at WOT. Therefore part throttle it's definitely looking at 02 and KS. That's why dudes get all bummed when they can't tune in closed loop boost. You don't have to be open loop to boost. Essentially open loop means it's ignoring 02 feedback and not compensating the calculated AFR. Open loop doesn't occur as often as some may think. It's actually supposed to be a rarer occurrence during normal driving.
I can check my service data again but I'm rather confident the computer doesn't care about KS below 3K because the 3.4 is inherently a noisy engine and it would receive too many false readings.

And yes, Cali fuels suck, and we have denser air as well. Excellent points sir.

 

[MTD]

Ya in open loop the ECU pretty much only looks at CKP, CMP,MAF AND TPS. Ignores the O2 is the important part. However, I'm also under the impression open loop only occurs when cold, and when at WOT. Therefore part throttle it's definitely looking at 02 and KS. That's why dudes get all bummed when they can't tune in closed loop boost. You don't have to be open loop to boost. Essentially open loop means it's ignoring 02 feedback and not compensating the calculated AFR. Open loop doesn't occur as often as some may think. It's actually supposed to be a rarer occurrence during normal driving.
I can check my service data again but I'm rather confident the computer doesn't care about KS below 3K because the 3.4 is inherently a noisy engine and it would receive too many false readings.

And yes, Cali fuels suck, and we have denser air as well. Excellent points sir.

I'd say most of us are in closed loop 95% of the time. It really depends on how much you beat your truck lol. I know mine only goes into open loop when I mash the pedal.

 

[4Reak Show]

I'd say most of us are in closed loop 95% of the time. It really depends on how much you beat your truck lol. I know mine only goes into open loop when I mash the pedal.

Agreed. That would fall under the Wide Open Throttle category. I'm researching knock sensor operation now. I do want to know for sure. So far factory manual pretty says nothing.

 

[MTD]

Agreed. That would fall under the Wide Open Throttle category. I'm researching knock sensor operation now. I do want to know for sure. So far factory manual pretty says nothing.

Factory manual has open/closed loop definitions I know. I'll send ya the PDF when I get home

 

[masphx]

Broke it open this morning. Anyone spot anything that looks 'off'...

 

[MTD]

Looks good to me. Hard to tell anything with out physically inspecting it with a feeler gauge to be sure, but from a visual inspection you are A okay!

 

[gamefreakgc]

Broke it open this morning. Anyone spot anything that looks 'off'...

Looks good so far. I'm thinking that if he rebuild the nose cone himself then the issue will be how it was pressed back together. That's where it gets a bit more complicated.

On the ping issue, it seems like the ping is vehicle specific. Some engines don't ping at all (mine ONLY pings at low RPM boost after driving for 2+ hours when it's really hot outside, basically hardly ever) and some people get the ping everytime they go into boost. It's really subjective.

 

[shootmymime]

I'm still saying your nose cone shaft is pressed in too far.

 

[kigmob]

isnt the knock sensor disabled in open loop? hence its called open loop? so i believe your mixed up on when the knock sensor is being read.

- you do live in California that has crappy fuel and so low to sea level.

The knock sensor doesn't correspond with open/closed loop operation. I think your confusing it with the O2/AFR sensors. I'm pretty sure 4Reak Show is correct about the 3000 RPM thing. This is what I have read from all of Gadget's stuff. Not sure if its documented somewhere by Toyota, but I am sure Gadget did some experimenting/testing to come to this conclusion. So the knock sensors would most definitely be operating when the vehicle is in open loop since this usually occurs well beyond 3000 RPM (for me atleast).

Speaking of knock, I purchased a TurboXs knock light off of ebay. Curious to see how it works. Hopefully it will make tuning for knock a bit more accurate. I never liked only relying on audible knock for tuning. Especially since my truck has loud tires/exhaust/supercharger/rattles/squeaks...

 

[masphx]

I'm still saying your nose cone shaft is pressed in too far.

How would I go about checking this and fixing it if it is true?