FC3S_GTUs

What are the most obvious symptoms of a blown rotor???? I am about to sell my car but am starting to have seconds thoughts now because I read somewhere that having a bad fuel filter/injector and bad/ripped vacuum lines can make your car feel like its running on one rotor. Haven't done a compression test nor did the "pull plug wires and listen for pst pst". Am I being too rash thinking it's a blown rotor? Half the power is lost, engine vibrates a lot, and idles but when I give it gas it shuts off..........ANY comments/suggestions would be appreciated.

Thanks

Audiofight

will it idle on its own for more than 10-20 seconds?

when mine blew the rear rotor, I had to fight to keep it running at low rpms. it was completely gutless but ran at higher rpms.

easiest thing to do, pull a plug and see what happens

FC3S_GTUs

It will keep idle untill I try to drive it....so I have to do the whole "manual - keep foot on gas and brake with handbrake" method untill i got home. What do I do after I pull a plug? The trailing or leading? Also what equipment(s) do I need to run a compression test?

black_sunshine

Your problem doesn't sound like a blown motor.... Since it dies when you give it gas, that leads me to believe that you've got a fuel injection problem. Check (or have someone do it for you) all your important sensors/solenoids/motors. Check for vacuum leaks by spraying carb cleaner (not when the motor is very hot!!!) on all the vacuum lines, or just dump water on all of them. If the idle increases with the carb cleaner, you've got vacuum leaks. If it dies with water, you've got vacuum leaks (or the water caused something to fail).

Every car I've seen with a bad rotor ( very little compression; 0-30psi on all faces) will still barely idle IF you can get it to start. But they don't die when you give them gas.

My current rebuild project has a bad side seal. It runs okay, idles extremely (feels like a full-race V8 at idle) rough, but revs just fine.

An easy way to see if you're not getting fuel on one rotor is to pull one of the vacuum caps (S4 only) off the passenger side of the manifold. Spray some carb cleaner (man I love that stuff) in the nipple and see if the idle smoothes out. Repeat for the other rotor. S5's require you to remove one of the "injector air-bleed" lines (located on the passenger-side of the manifold, on either side of the ACV).

To do the compression "sound check," you remove the EGI fuse in the engine bay. Next, pull one of the top (trailing) spark plugs. Crank the engine and listen for three EQUAL "PSSSHTTT" noises. Keep in mind that my motor with a bad side-seal sounded great with this method.

To do the "hack-job" compression test, you'll need a cheap automotive compression tester. Remove the valve-core (check valve) from it, and attach it to the trailing hole. Crank the car and look for 3 EQUAL bumps of the gague. The quality of the gague is a factor in accuracy, as is your ability to watch a needle bouncing around VERY quickly. Still inaccurate, but more accurate than the sound check, because here, my bad motor showed ~75psi on two faces and ~40psi on the other.

To have a REAL compression test done, you'll need to find a dealer (noooooooo!), an individual, or a specialized shop that has the actual rotary compression tester. Guaranteed accuracy; mine showed 85psi, 84psi, and 36psi.

Good luck!

FC3S_GTUs

Holy guacamole...thats a lot of info you gave me there...i really appreciate you taking your time and helping me out...
what i meant to say earlier was that it idles fine but once i give it gas and THEN let go it will idle for maybe 1/2 sec. then die.

im going to do the "sound check" tomorrow and see where that takes me...pull out each trailer plug...each rotor housing...one at a time....3 equal pshhht pshhht pshttt = good

till then....

RotaryResurrection

iTrader: (8)

www.rotaryresurrection.com ---> tech ---> compression check

Just do it.