Car Wont Idle Unless I Hold The Gas Pedal

[laserfast]

HEY THERE...I HAVE A BIG PROBLEM WITH MY 1990 PLYMOUTH LASER RS 5-SPD TURBO...WHEN I TRY TO START MY CAR IT JUST KEEPS TURNING OVER.....UNTIL I PRESS THE GAS PEDAL THEN IT WILL START...BUT IF I DON'T KEEP GIVING IT THROTTLE THE CAR WILL DIE...THE CARS RPMS REALLY DON'T EVEN CHANGE WHEN THE GAS IS PRESSED.... I HAVE BEEN TOLD THAT THE ISC CAN GO BAD BECAUSE IT WILL WEAR DOWN AND SHORT OUT...THEREFORE SCREWING UP THE ECU...ALSO THEY SAID WHEN I LOOK AT THE ECU LOOK FOR A BURN MARK....WELL I TOOK OUT MY ECU AND OPENED IT UP...ON THE BACK PLATE THERE IS WHAT LOOKS LIKE A BURN MARK AND IT SMELLS PRETTY BAD SO I AM FIGURING THAT THE ECU WENT BAD(THE ECU WAS REMANUFACTURED ALREADY)
THE KID I BOUGHT IT FROM CHANGED THE ECU ONCE....AND NOW I THINK I KNOW WHY...I THINK THE ISC IS BAD

ONE OTHER THING I AM THINKING IS THAT IT MIGHT BE TIMING BUT I AM NOT SURE I STILL HAVE TO DO SOME TESTS

PLEASE LET ME KNOW WHAT YOU THINK AND IF I AM ON THE RIGHT TRACK OR NOT WITH THE ISC AND THE ECU

THANX LASERFAST

 

[Ultimatedsm]

Check your BISS screw on the throttlebody, maybe it needs adjustment. If that doesn't work, it could be your ECU considering you have a 1G. Their CAPS seem to leak over time. I would get that checked.

 

[laserfast]

when i had my car going i messed with it a little but nothing changed.........today 12-7-05 i had my ecu checked by an electrician and one of the capacitors i guess were not very good......one of the poles that are soldered were all brown and crusty and there was a what looks like a burn mark on the back plate...........so they were going to change the capacitor and check the others..

thanx for throwing in some info but i still need help on what other things could have caused this

laserfast

 

[calcifer]

Just caused by old age. 1gs are notorious for this.

 

[aadperformance]

If you want to check the operation of the ISC unbolt it from its location, keep it plugged in and then have someone go turn the ignition to accel and watch to see if it moves in and out. If it does then it is working properly.

 

[gurmanator]

could be as simple as a vaccum hose...if you suck to much air the car wont run...its happend to me.

 

[laserfast]

thanx for the help............ill got on it right away and check the isc that way also and ill check the vaccum lines really in depth this time..........on the ISC i did an ohms check on the terminals and it was supposed to be 28-33ohms.....on the 1st to 2nd terminal it read 29.5 and then on the 5th it was 29.6 so that seems good but ill check with taking it off
thanx
laserfast