# Bad idle, stalls randomly, black smoke out exhaust, won't rev past 3k rpm, VERY rough **URL:** \ **Category:** SON240sx Automotive\ **Created:** [January 20, 2013, 11:39am UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297 "2013-01-20T11:39:06Z")\ **Posts on this page:** 16\ **Page:** 1
**Author:** ![d3boy2002](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/d3boy2002/32/6209_2.png) [@d3boy2002](https://forums.speedlife.net/u/d3boy2002)\ **Post date:** [January 20, 2013, 11:39am UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/1 "2013-01-20T11:39:06Z")
So I was driving around a month or so ago and i got one or two random misfires, and the power would just cut for like .5 of a second. I kept driving, and eventually, the car got to a point where it would just stall. It didn’t originally start up (I had to give it a lot of gas), so I left it hanging for a few minutes, and started it up again. It started right up, but on the drive home, the car kept dying. Now, I can start the car up, but it will not stay alive for too long (maybe 3-5 minutes before stalling, and I have to restart it). There’s a lot of misfire going on, black smoke out my exhaust (from misfire I think), is very rough, slightly louder than usual I think, and it won’t rev past 3k rpm no matter how much gas I give it. My AFR gauge shows the usual 14.7ish and is very consistent. My PSI gauge doesn’t jump around (not that I can see) but it seems like my turbo is working extra hard to get the car moving. I thought it was the fuel filter, so I changed that up, but no difference. Any ideas? I’m thinking clogged cat, coil packs, or fuel pump. ---
**Author:** ![latins13](https://avatars.discourse-cdn.com/v4/letter/l/e19adc/32.png) [@latins13](https://forums.speedlife.net/u/latins13)\ **Post date:** [January 20, 2013, 11:55am UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/2 "2013-01-20T11:55:42Z")
Injector, fuel pump or faulty mass air flow sensor mine was doing the same thing but I have a ka ---
**Author:** ![purestock240](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/purestock240/32/5729_2.png) [@purestock240](https://forums.speedlife.net/u/purestock240)\ **Post date:** [January 20, 2013, 11:59am UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/3 "2013-01-20T11:59:06Z")
clean out the maf sensor? ---
**Author:** ![latins13](https://avatars.discourse-cdn.com/v4/letter/l/e19adc/32.png) [@latins13](https://forums.speedlife.net/u/latins13)\ **Post date:** [January 20, 2013, 12:05pm UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/4 "2013-01-20T12:05:33Z")
Or just start the car and start Unplugging each injector and if you don’t notice the noise getting louder or a more misfiring its your injectors ---
**Author:** ![Singh](https://avatars.discourse-cdn.com/v4/letter/s/43a26b/32.png) [@Singh](https://forums.speedlife.net/u/Singh)\ **Post date:** [January 21, 2013, 9:25am UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/5 "2013-01-21T09:25:15Z")
Start with your maf sensor. Disconnect it and see if problem gets worse or stays the same. Then try your injectors, also check the impedance on each injector. Then check your fuel pump. coil packs you can visually inspect for cracks. ---
**Author:** ![Ciaran](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/ciaran/32/5612_2.png) [@Ciaran](https://forums.speedlife.net/u/Ciaran)\ **Post date:** [January 21, 2013, 10:28am UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/6 "2013-01-21T10:28:33Z")
vac leak? ---
**Author:** ![d3boy2002](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/d3boy2002/32/6209_2.png) [@d3boy2002](https://forums.speedlife.net/u/d3boy2002)\ **Post date:** [January 21, 2013, 5:55pm UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/7 "2013-01-21T17:55:23Z")
Before this when I had a problem of just bouncy idle, I replaced my BOV and the problem was gone for a bit… but then the new bov started leaking. Could it be that my clogged cat is putting more pressure on the BOV or something? o.O I checked the injectors and MAF and they seem to be working fine. ---
**Author:** ![randy240sx](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/randy240sx/32/5740_2.png) [@randy240sx](https://forums.speedlife.net/u/randy240sx)\ **Post date:** [January 22, 2013, 5:46pm UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/8 "2013-01-22T17:46:12Z")
your cat has no relation to your BOV ---
**Author:** ![JonathanPrem](https://avatars.discourse-cdn.com/v4/letter/j/6f9a4e/32.png) [@JonathanPrem](https://forums.speedlife.net/u/JonathanPrem)\ **Post date:** [January 22, 2013, 6:31pm UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/9 "2013-01-22T18:31:05Z")
^ i Lol so hard at the Cat and bov. Sorry had to. Bad Idle can also be dirty Idle air control value. How old is your fuel filter and pump? Remove the spark plugs and check it. ---
**Author:** ![sick96gst](https://avatars.discourse-cdn.com/v4/letter/s/dec6dc/32.png) [@sick96gst](https://forums.speedlife.net/u/sick96gst)\ **Post date:** [January 22, 2013, 6:54pm UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/10 "2013-01-22T18:54:40Z")
I’m guessing you have a sr? Unplug each injector, then each coil pack, or pull wires on ka. If there is no change when one is removed start there. Also do a boost/vac leak. If none of those move on to compression check. Also you should check that your turbo isn’t sized, in pieces, and that your waste gate is working. What mods are you running? ---
**Author:** ![randy240sx](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/randy240sx/32/5740_2.png) [@randy240sx](https://forums.speedlife.net/u/randy240sx)\ **Post date:** [January 22, 2013, 8:18pm UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/11 "2013-01-22T20:18:32Z")
> [@JonathanPrem](#): > > ^ i Lol so hard at the Cat and bov. Sorry had to. Bad Idle can also be dirty Idle air control value. > > How old is your fuel filter and pump? Remove the spark plugs and check it. Lol I second the IACV also water temp sensor is a possibility ---
**Author:** ![trillex905](https://avatars.discourse-cdn.com/v4/letter/t/3da27b/32.png) [@trillex905](https://forums.speedlife.net/u/trillex905)\ **Post date:** [January 23, 2013, 7:16am UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/12 "2013-01-23T07:16:32Z")
![http://www.clublexus.com/assets_c/2013/01/Baby-turbo-is300-thumb-600x428-890.jpg](http://www.clublexus.com/assets_c/2013/01/Baby-turbo-is300-thumb-600x428-890.jpg) ---
**Author:** ![PatGlocks](https://avatars.discourse-cdn.com/v4/letter/p/9fc29f/32.png) [@PatGlocks](https://forums.speedlife.net/u/PatGlocks)\ **Post date:** [January 23, 2013, 10:50am UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/13 "2013-01-23T10:50:08Z")
Sounds like what my KA was doing and that was timing related, a buddy of mine said he was also having the same issues(notch top sr) and he played with the CAS and got everything sorted out. Try other peoples suggestions before you try to fuck with timing tho. ---
**Author:** ![drewce](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/drewce/32/5733_2.png) [@drewce](https://forums.speedlife.net/u/drewce)\ **Post date:** [January 28, 2013, 11:17am UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/14 "2013-01-28T11:17:42Z")
Sounds like a Maf problem. Also Check the wiring going to the maf. ---
**Author:** ![Lumpy](https://avatars.discourse-cdn.com/v4/letter/l/3da27b/32.png) [@Lumpy](https://forums.speedlife.net/u/Lumpy)\ **Post date:** [March 29, 2013, 8:12am UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/15 "2013-03-29T08:12:54Z")
Boost leak vac leak or maf ---
**Author:** ![GetARide](https://avatars.discourse-cdn.com/v4/letter/g/e495f1/32.png) [@GetARide](https://forums.speedlife.net/u/GetARide)\ **Post date:** [March 29, 2013, 12:55pm UTC](https://forums.speedlife.net/t/bad-idle-stalls-randomly-black-smoke-out-exhaust-wont-rev-past-3k-rpm-very-rough/228297/16 "2013-03-29T12:55:18Z")
Throttle Position Sensor could be facked too