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please delete

Posted: February 16th, 2012, 7:36 pm
by Kbdread
Good day as topic says, the engine runs well most of the time but sometimes i get a rough random idle, loss of power and even cut off once or twice. Start back and it drives normal again for a while. I'm looking for coil packs and plugs right now. What are your suggestions??

Re: Rx-8 intermittent misfire, sometimes cuts off.

Posted: February 17th, 2012, 1:56 pm
by ImamurA
most likely fouled plugs or worn plugs...

do you ever start the car and shut it off before it fully warms up? (like starting it up in the morning and just driving out of the yard then parking it back)...also run the engine to redline a couple times and let the higher exhaust temps clear out the carbon...

Re: Rx-8 intermittent misfire, sometimes cuts off.

Posted: February 17th, 2012, 3:16 pm
by DSM_05
Sounds like fouled plugs, and you could be on the verge of flooding.

Surprisingly, weak plug wires can also be the cause. stock ones don't hold up very well past 50k mileage.

replace those first since that's a normal replacement item along with plugs. If that doesn't help, look at the coilpacks.

like I told you, GT_RACING has all in stock.

Re: Rx-8 intermittent misfire, sometimes cuts off.

Posted: February 17th, 2012, 7:13 pm
by Kbdread
Thanks folks, i plan on changing the plugs and wires. The coilpacks are a bit pricey so i'll change those last. I always let the engine warm up to operating temps before driving or shutting off engine. Redlining is not a problem to remember, the sound is too addictive.

Re: Rx-8 intermittent misfire, sometimes cuts off.

Posted: March 17th, 2012, 5:42 pm
by Kbdread
Back again, changed plugs, wires and coil packs all brand new stuff, still getting the rough erratic idle after the car drives and gets to operational temperature. Any more suggestions?

Re: Rx-8 intermittent misfire, sometimes cuts off.

Posted: March 18th, 2012, 11:51 am
by Kbdread
anyone?

Re: Rx-8 intermittent misfire, sometimes cuts off.

Posted: March 19th, 2012, 8:52 am
by ImamurA
leaking/dribbling or clogged injectors can cause rough idle and cutting off...have someone take them out and inspect them and clean them...

Re: Rx-8 intermittent misfire, sometimes cuts off.

Posted: March 19th, 2012, 9:14 pm
by Kbdread
Thanks for the advice, no harm in cleaning injectors, but the car works perfect until you drive it and the temperature reaches about half scale. A clogged injector should cause poor operation all the time, not so?

Re: Rx-8 intermittent misfire, sometimes cuts off.

Posted: March 20th, 2012, 8:47 am
by ImamurA
oh yeah...i forgot u said the problem occurs when the car is warmed up....

the throttle position sensor gives symptoms very similar (rough idle, cutting off when warm)....have it checked...when the car is warm check the voltages both at closed and at wide open throttle...there is a certain range of voltages at which the tps works perfectly...the factory service manual has the range for both closed and open throttle...a good mechanic will be able to check it...

Re: Rx-8 intermittent misfire, sometimes cuts off.

Posted: October 21st, 2012, 9:36 pm
by Kbdread
Finally sorted out, I took out the catalytic converter, now I can run the car hard and it doesn't cut off. Wish I tried that first but all the new parts wouldn't go to waste.