skrassow

Wouldnt a belt slipping cause these symptoms? When it starts reving harder the belt begins to slip, so boost falls back. If its slipping enough you may not be able to reach redline. I just thinking out loud here, so I could be way off. Trying to find the simple answer before you go tearing things apart. Is there any sign of slippage? worn belt, black powder (belt residue) around the pulley, etc? Give me a bit and I will look at my truck and see what kind of movement I get around the bypass valve to compare to yours.

skrassow

Well I cant get the video to open up on the computer (its a crappy cell phone video anyway). But I dont notice AS MUCH movement in my bypass valve. Although there is some. I dont have anyone around to hit the gas for me, so I was just trying to flip the throttle by hand. Maybe someone else can get a good comparison for you.

If you send it in, I seem to remember reading somewhere that there are other companies that will do a rebuild for cheaper than Magnuson. Im sure mine will need it someday so Im interested to see where this goes.

b18vteceg

i do have a lil bit of black powder but i assumed that was from the brand new belt from toyota....i have a brand new pulley on the charger and the dynamic tensioner is working just fine so i dont think its a slippage problem but hey im no expert....just callin it as i see it.


i will call magnuson today and see what their prices are and what all a "rebuild" includes

but ya some comparison videos would be great!

mastacox

I seriously doubt it's a slipping belt. You would first of all know that the belt was slipping due to a ton of squealing. Besides, if the belt is slipping enough to completely lose boost there is way too much resistance somewhere in the supercharger.

My guess is the bypass valve is broken/not working properly, preventing the proper amount of boost from reaching the engine. For what its worth, I got my supercharger rebuilt about a year ago for about $375, because they didn't have to replace the rotors. If they have to replace the rotors, expect the bill to be about $750.

skrassow

Well I have heard SC belts slip without any squealing at all. But you are right, if the slip is that bad that its a total loss of boost then there is some serious resistance. So that would point you back to having the SC rebuilt.

FWIW, b18vteceg I have a brand new belt on mine as well as a brand new pulley and have no powder at all. I would say there is some slippage...caused by other issues maybe. But like you said...Im no expert. I just look for what seems to make sense.

Please let us know what you find out from Magnuson. I may send mine to them sometime and have them look at it/rebuild. Its only got 30k on it now, but I think Im a bit short on the psi.

b18vteceg

spoke with David at magnuson today and he told me if im losing boost i have a "O" Ring that is bad. and there are 2 of them and they are on that L shaped deal that i asked should this be moving or not. well the answer is no it should not.....maybe a little tiny bit but not like mine was moving.

so i got home pulled that unit off and tested the bypass valve.

easiest way to test it is press the metal shaft all the way toward the black canister.....and place your thumb over the vacuum port and if the shaft doesnt move and the valve holds the shaft in place then you are good if it goes back to its original position you have a tear in your diaphragm (sp?) this is what david from magnuson told me.

bypass tested great no tear and no leak there. so i pulled the L shaped bracket off after a major fight with the C clip that holds it in there, and sure enough both seals were very messed up. went to napa and got 2 O rings and placed them in their new homes.

put it all back together and i can hit 6 psi of boost now but when im throttling up and pedal is to the floor i am still loosing the boost. so tomorrow is another call back to david to see what's going on im getting closer but the saga continues.....

skrassow

Thats great intel. Keep us posted.

Greg_Canada

Is the bypass valve leaking/faulty?

b18vteceg

alright here's an update.

spoke with david again at magnuson and he told me its possible that one of the seals throughout the charger housing could be bad.

so i told him i would take the charger off and place the regular manifold back on and see if the no power above 4k and high idle still are there.

sure enough they are.

with the regular manifold on i idle at about 1100 and anywhere above 4k i hear the intake change tone and it really starts gasping for air but i feel the motor just lose power. something is wrong i just dont know what. i know someone brought up knock sensor but dont they usually throw codes?

and as far as i know there is no way to adjust idle like the 3vze are there?

every hose is hooked up there are no leaks, cracks, breaks, etc....

new plenum manifold gaskets....

i have ZERO vacuum leaks but still have a 1100 idle? what else would cause this? i changed the IAC valve and that didnt make any difference. could a knock sensor cause terrible upper end power and high idle?

so basically i think the charger was working alright but it was just magnifying my main problem.


thanks guys and hopefully i can figure this out or maybe someone has the magical answer for me!



btw greg....yes i tested the bypass valve and its working and not leaking

skrassow

I would think a knowck sensor would throw a code...but now Im really curious to see how this turns out. I wish I had more info to help you with...but I got nothin

b18vteceg

new intake manifold and knock sensors currently going in.....with all new gaskets.....lets see what happens!

b18vteceg

replaced both knock sensors and all intake manifold gaskets

another set of injectors i had and a different stock FPR i had

same problem....although idle has improved.....im now idling at around 900 rpms which im fine with but whats odd is when i turn on the ac....the idle drops down....and stays down....shouldnt the motor see the load on it and compensate for it?

honestly the only thing i have not replaced is the MAF and the o2 sensors

and again i have no leaks, cracks, blah blah.....

and when i get to about 4000 rpms the motor just gives up and has no pull at all.....its almost worse than in 5th gear with the 3.0 going 30 mph and trying to floor it....that's how it feels....but when im in 2nd.....going 30.....

and of course....no codes....

tomorrow i guess ill look into spark plugs? wires? compression? and i have another set of coil packs i might try as well but i really dont think it's a spark issue....

any ideas would be much appreciated

skrassow

I would for sure check compression. Maybe talk to a mech at the dealership...I know some are up tight about giving advice like that, but I have had a few help me out with stuff before.

Do you have a scan tool? You should be able to get a look at your timing and what not there. Might at least help narrow it down.

b18vteceg

i just have the basic scan tool to read codes i have been looking into a tool that i can run with my laptop tho to get a little more info about the motor and what the motor is doing.

b18vteceg

alright time to bring this post back from the grave.....


last weekend i finally went back to work on this damn thing. i pulled the entire supercharger apart and checked bearings and resealed everything

(i know this isnt the problem but i want to put it all back together and know the charger is ready for 50k or more miles when i finally get it running right)

also replaced all spark plugs and wires....ngks for both.....the plugs i pulled out looked just fine....not super white or anything

i still have the problem of when i max throttle at around 4k the motor sounds like its trying to suck ALOT of air but my speed and rpms dont go up very fast at all!!!

and yesterday i finally! threw a code P0171

which is too lean bank 1 so maybe there is a little light at the end of this tunnel.

im going to pick up a new fuel filter and install the 3.4l fuel pump i have.....

here is something i noticed and i dunno if this is normal or not.....when i take my gas cap off i get this HUGE pressure release....is this normal? i thought tanks have vents on them so they dont pressurize?? my work van doesnt do it and either does my acura TL.....anyway just an odd question...

thanks guys hopefully i can get this damn problem resolved and start enjoying boostin around town!

Greg_Canada

Yea, mine does the gas cap thing too, it's normal.
You dont have a wideband o2 sensor yet eh?
Have you cleaned your MAF?
are the o2 sensors NGK or bosch?

b18vteceg

no wideband o2 yet.....

i dont know the brand is there a way to tell? i just have stock ones the motor came with.....

and yes i have cleaned the MAF several times.....

hopefully i will get my BR-3 today.....so im gonna run my laptop and hopefully check out whats going on realtime and maybe this will show me some answers.....ill get back to you guys.....

who sells best wideband o2?

b18vteceg

alright so i only had a short time to test with br-3 i really need someone else to drive while im watching it i almost killed myself hahahah....

but this is what i found so far....when im off throttle is shows 9.4% and when im wide open it shows 74.9% is this right???? shouldnt wide open be 100%?

next fuel trim seemed to stay in the 0 range most of the time unless i was off throttle or something then it would move a little

air temp is around 90 which is what it is outside

air volume was around 14 lbs wide open

and timing advance was 15 at idle and hung around 30 (basically maxed out) the rest of the time.....

some things dont seem quiet right but again no codes and drives fine just no top end power.....

mastacox

Sounds like you're going to want to check your AFR's... but I'm surpirsed that your fuel trims are staying near zero. You might be experiencing some severe top-end leanout which would mean a loss of power and also a dangerous spike in EGT's. Hopefully you haven't damaged your pistons or valves with your full-throttle test-runs...

Have you fixed your boost problem yet, or does it still jump around like in the video you showed? Do you have a Walbro fuel pump?

b18vteceg

yes boost problem has been fixed but the problem is in the upper rpms the motor just seriously sounds like its suckin so hard for air but my rpms dont go up very fast at all so i start loosing boost....but if i am going like 25 to 30 and put it in 4th and for a lack of better term "bog" the motor the boost with spike to 6 psi and stay there until the motor gets up to about 4k rpms then the sucking noise starts and my power and boost go bye bye....motor still has solid compression.....last time i did it they were all around 185.....i can do it again but im pretty sure its still good....only did it about 2 weeks ago and barely ever drive it....and when i do its granny shifting under 4k.....disgrace to the charger i know =[