ok ive been trying to figure this out for at least 4 months now troubleshooting everything under the sun and im spent and just literally want to burn it to the ground

backround info....

stock ls motor w/ a pnp head running on a p75 ecu

now the motor runs great up top and gets decent gas mileage....yet soon as you get off the trottle it dies....

put the vac/boost guage on it and at idle it barely pulls (10in hg) and i loose all brake vacuum...

ive tried multpile ecus, iac's, double checked wiring etc...and im totally stumped

any help is greatly appreciated!

 

have u checked vaccum lines?

 

ya..finally got it idling somewhat w/ a new tb a friend brought over....apparently my tps **** the bed and was causing it not to even idle properly

now it starts at least and maintains a somewhat steady idle

now my problem seems to be timing based...no matter how much i advance the dizzy i cant get anywhere w/ in my timing spec...and it sucks because i got this motor for free and until i pulled it apart today to fix a HG issue i didnt know it was PnP w/ dual springs etc....so bonus there but i think the fact that im only pullin still low vac #'s it has somethign to do w/ it

also im not to sure if the head was milled...which could be causing the slight offset im seeing on my timing...it runs well up top....but down in low loads its almost like it has bent valves....slight sputtering....

 

low vacuum and timing issues usually means ur timing belt is off.. had a similar problem with my friends b16... ran like **** and timing was way off... timing belt was 2 teeth off on the intake cam... CHECK you timing marks!!!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by g2daturbo &raquo;</TD></TR><TR><TD CLASS="quote">low vacuum and timing issues usually means ur timing belt is off.. had a similar problem with my friends b16... ran like **** and timing was way off... timing belt was 2 teeth off on the intake cam... CHECK you timing marks!!!</TD></TR></TABLE>

going to today...but i doubled checked it yesterday and they were spot on

 

up,

it is weird, because 2 days ago we did the head gasket and when we put the timing belt back on we set TDC by the alighment mark on the cover by the man crank pulley, AND found tdc with a screw driver on the top of piston on cylinder one,

now he can't get his timing right and it has like 0 vacume it all points to bad cam timing, but the keyways on the cam gears are good, we checked, the timing islines up, but we have to keep the dizzy at FULL advance to even get the car to run, and we can never get the timing markts to line up when using the timing gun?