well my buddies just got his motor rebuilt for boost(je piston and eagel rods)and has just finished installing it but hes haveing really high reving problems..once he starts the car it would rev really high and not stop until u turn off the car..has anyone ran into this problem ?what could cause the motor to rev so hard and high?do u think its a bad map senser?any help would be greatful.

have you checked the TB while it's running? is it sticking at all. or not closing all the way? is the gas pedal down at all(on it's own).

just suggestions besides the sensor.

Make sure that everything that is supposed to be connected to the intake manifold is connected. Including the EGR pipe on both ends.

everything is pluged in right to his knowledge and he has checked the tb and it was fine(gas pedal was never pressed)the car revs on its own whithout pressing the gas.really wierd...let me list his setup if it helps any:stage 2 hrc turbo kit,howell bottom end kit,vortech fmu,aem camgears set at 0,aftermarket pulley,greddy type s bov,safc,greddy profic b,spec stage 3,aftermarket exhuast,most of the monitoring guages except fuel pressure guage,and stock injectors..he still thinks it the map sensor and is gonna get a new one tomorrow and see if it helps but if u guys can think of anything that might cuz this let me know...thanks

Still sounds like mentioned above, did he seperate the upper and lower intake? Maybe the gasket didn't seat on that or the TB.I think if the mapp was bad it would throw a code or something.also he checked his throttle cable and all that?Really looked at the butterfly to see that it was closed.Have in put his hand over it while running to see if that helps? :shrug

It's the throttle body gasket. Put some silicone on both sides of it, but be sure not to get any in the intake or tb. Make sure and tighten it down real good. Oh and use non-adhesive silicone.

holy shit, this has nothing to do with the idle but if he plans on doing anything more than like 5-6 psi then he sure as shit better have bigger injectors and a fuel pressure guage. you might want to tell your buddy that.

Edit: As for the idle, tell him to clean his IAC and set the tip to protrude 1" from the base of the IAC. good luck

one thing i forgot to mention:when he unplugs the map sensor the car starts and then dies but if its plugged its just revs really high..could the tps sensor be bad?well hes gonna double check the throttle body and gasket tomorrow when he gets off work.if that doesn't fix it what else would cause the engine to rev high on its owne...strange

that happened to a friend of mines saturn. the tps thing was all fucked up and didnt seat correctly. it let air seep through and held an idle at like 2500rpm. make sure that is good, and if it is id check gaskets again.

I'm going to say it is a vacuum leak. I would recheck absolutely everything.

Did you guys mess with the TB when the car was apart? Meaning did you take the sensors off to clean anything. What Im getting to is, if you mess with the IAC and its moved out of setting it will make the car rev really high until you drive the car above 40 MPH. At 40 MPH the IAC will reset itself.

Good Luck
DJ

Did you guys mess with the TB when the car was apart? Meaning did you take the sensors off to clean anything. What Im getting to is, if you mess with the IAC and its moved out of setting it will make the car rev really high until you drive the car above 40 MPH. At 40 MPH the IAC will reset itself.

Good Luck
DJ

Did you guys mess with the TB when the car was apart? Meaning did you take the sensors off to clean anything. What Im getting to is, if you mess with the IAC and its moved out of setting it will make the car rev really high until you drive the car above 40 MPH. At 40 MPH the IAC will reset itself.

Good Luck
DJ

okay he said he gots the car running and took it for a test drive and first gear seems fine but 2,3,4 will not past 4,000 rpms and sometime the car will just die..any thoughts?plus his egt gauges gets in the 1600s!!

he said he replaced the iac and it stop the high reving but 2,3,4 gear will not past 4000 rpms,1st gear seems fine though..plus the car dies on him every 50 feet after he gets it moving..

any idea guys? crank sensor maybe??

Now it kinda soounds like the MAP. Your running lean, according to the EGT. So your getting too much air, and not enough fuel to compensate. You could possibly also have a vac leak somewhere, but Ive never heard of a vac leak keeping the car from going over 4k. Are you throwing any codes? You do have the PCV hooked up, right?



P.S. Sorry about the triple post, I dont know what the hell happened!!

same thing happened to me, tell him to check and make sure there is power to the fuel cut defender, the one that interrupts the singal to the map sensor. i put an inline fuse holder on mine, but, duh, forgot to put the fuse in. drove myself crazy trying to figure it out.