Massive Loss Of Power!

[ekips009]

Alright here is the story... i was on a pretty big road trip from montna to arizona and was driving up a pass through utah with my a/c on and my cruise control on, and my car started to max boost around 15 psi (thats what my autometer gauge read) so i decided to take it off cruise control and turn off the a/c so i didnt stress the engine to much... then i started to pass a semi truck (with cruise control off boostin around 10) when my boost gauge started to jump all over the place and i had a huge loss of power! so i pulled over to the side of the road... and shut off the car... looked around didnt see anything majorly wrong so i left the hood open and started it back up, idling was fine but as soon as i revved it passed 2500 it would start to vibrate really bad... and i also noticed that at idle my vac was at 10 inHg instead of the usual 15inHg... so i looked around some more and saw that my ic hose comming from the turbo to the ic was moved alittle bit so i losened it and pushed it back on some more, it wasnt off though it still had about an 1.5 to 2 in till the end... so i started it back up and let it run for a little longer when i decided i really needed to get off the side of the interstate so i started back up the hill very slowly and back down and it seemed to be working ok but my vac was still low... with all my power still not back yet... so if you guys have any suggestions that would be very helpful! and thanks for your time!!! : )

 

[96mitsugsx]

Are you still running a cat? It might be clogged.

 

[z24frank]

Check your coil pack at least thats what it was doing on my 1g!

 

[ekips009]

yeah just the usual boost leak advice....btw, your only pulling 15 inHG when you were running good...theres gotta be a leak, im running 17inHG on idle, and 22inHG under de-acceleration....

Really? well how would i check for a leak in my vaccume??? is it just by the boost leadk because my boost leak test was fine... i wouldnt be supprised if this was the cause but i just dont know how to check with the vac... and my coils is good... well when i did an engine diag test on it before i left... and yeah i still have my cat... how would i check if its clogged? thanks

 

[r1991_4g63t]

Timing belt jumped a tooth... Or someone mysteriously swapped a set of cams into your ride while you weren't looking... I'd bet on the timing belt skippage.

the only things ive ever seen cause low vacuum readings like that are a install on the gauge or timing a took off, but since you said timing was ok i'd check the guage, the fittings are one of the most susceptible to leaking

 

[ekips009]

yeah i mean if it was my coil i would have some CEL's i would hope ; )... and im clean...

 

[r1991_4g63t]

i been workin on cars for along time and ive NEVER seen a coil cause readings like that, is it a steady 15in? or is it jumpy
and are you 100% positive the cams are lined up right? even one tooth can still look really close to being right

 

[chanley talon]

What is the oil pressure? Vibration and loss of power sounds like oil pump or balance shaft trouble . The vac goin from 15 to 10 could be because there is a strain on the motor . This did happen to me the same way. What happened in my car was the rear balance shaft baring decided to break .It spun around until it shot into the pan then i got vibration. During all this time my car kept oil pressure . But vibration told me where to look.

 

[ekips009]

i been workin on cars for along time and ive NEVER seen a coil cause readings like that, is it a steady 15in? or is it jumpy
and are you 100% positive the cams are lined up right? even one tooth can still look really close to being right

Yeah im 100% shure they are lined up right... i actually just replaced all the belts and bushings right before i left on this trip and have everything lined up Perfect! but if it skipped a tooth it would be running alot worse than this... atleast when my older bmw's distributor got bumped and pushed my timing off it was alot worse... the belt was my first guess but it all checks out... the vac is now a constant 10inHg which is really low but my boost is constant 15 psi now...

 

[ekips009]

What is the oil pressure? Vibration and loss of power sounds like oil pump or balance shaft trouble . The vac goin from 15 to 10 could be because there is a strain on the motor . This did happen to me the same way. What happened in my car was the rear balance shaft baring decided to break .It spun around until it shot into the pan then i got vibration. During all this time my car kept oil pressure . But vibration told me where to look.

yeah i have normal oil pressure... (around 10 at idle when its warm and under a load... not much over 70 or so, i read the manual and its within spec..) even when it happened that was the first gauge i looked at and it was good... but the funny thing is when i started it back up and left the vibration was gone... and it hasnt come back?!?!? im sure i got it all right when i replaced everything, i was really careful with every step when i was repalcing my belts and bearing...

 

[ekips009]

hmmm well it would heat up or something after a while though right?

 

[r1991_4g63t]

if your only making 10in of vacuum i would NOT be trying to make boost whatso ever. unless the guage is just wrong, but if not you got a problem that needs fixing

 

[ekips009]

if your only making 10in of vacuum i would NOT be trying to make boost whatso ever. unless the guage is just wrong, but if not you got a problem that needs fixing

^^ yeah i know but thats what i am trying to fix! thats why i made this thread! i need help finding out how to fix it!!! < this is me trying to figure out my car...

 

[r1991_4g63t]

ok but until you fix it dont make boost

 

[ekips009]

well i havent been driving it much... but do you have any more ideas? because im running low on what else it could be!

 

[ekips009]

so am i just not supposed to drive my car... everything came up clean...

 

[ekips009]

so i got a friend to help me out with the boost leak check and i couldnt pressurize the system past 11psi, last time i checked it i could eaisly go all the way up to 15 or more... and when i got it up to 11 i could hear a small leak around the throttle body, and when i moved the throttle plate the leak almost stopped... does this ring any bells? thanks