Very Rough Idle

[Tsensational]

Its strange, it happens only when I've been driving freeway speeds and slow down. The roughness only starts when the automatic transmission switches to 1st. The entire car shrudders.

It feels like its not getting enough air but I've checked all the parts and they seem to be on correctly so I'm not sure.

Another thing is the daytime running lights dim when the engines struggling too. When the RPM wavering drops to around 300RPM, the lights get dimmer and when its back up at the normal 600, the lights are normal.

Anyone have any solutions or suggestions or anything?

Edit: Not Brat box. Removed it and nothing bad happened

[Ricoswave]

Battery/Alternator could be going. Mine shit the bed at like 1,000 miles.

Other possibilities include bad gas or a dirty MAF sensor.

[Tsensational]

I sincerely hope its the battery. I took out the MAF earlier to see if there was anything on it and its as shiny as when i first got the car. As for gas, i filled up with slightly higher grade gas if maybe the octane too low etc.

[FuryMiloh]

put fuel injector cleaner in your gas, your engines probably grimmy inside

[Tsensational]

sounds plausible too. I'll try it out today.

[FuryMiloh]

if your puting low grade gas in your car, it tends to make the pistons grimy and sticky, that is usually what will make your car idle all out of whack, put the fuel injector cleaner in your gas after you fill her up to the top, thats so the cleaner soaks into the gas

[Tsensational]

fuel cleaning didnt work. I really dont want it to be the alternator..

[dentedz71guy]

go to autozone, they'll test it for free.

[Tsensational]

Still havnt had time to have this sorted out with work and all. Interesting thing though. It seems to only have big problems when the weather is hot. Maybe just a coincidence.

[horse-eater]

its not gonna be the alternator. not like that.

the lights dim because when the motor isnt spinning fast, niether is the alternator.

what mods do you have on the car. it may be you torque converter lockout sticking. bubt i need to know mroe about your car.

[Tsensational]

Ripp's Bratt Box, F5 Cold Air Intake, RRE Headers and RRE's exhaust.

Nothings gone wrong for 20k miles so far though.

I'm gonna take out the Brat Box first and see what happens.

[Tsensational]

Honestly I wouldn't be surprised if it was the torque converter. Something goes wrong when the automatic tranny switches gears...like the transmissions bogging or something.

[Tsensational]

Well, tried taking off the brat box. Problem still persists. Gonna take it to the stealership to see whats up with it.

[Tsensational]

Stealership wouldnt even touch it because it was modified apparently. Then on the way back I got ticketed for blacked out taillights. 25 miles for a ticket. I'm a little agitated.

[psy-q]

If it's not throwing a check engine light then it's probably the transmission. Since that isn't modded the dealership has no excuse for not touching your vehicle. If your in the US the law will protect you.

It's up to the dealership to prove that the problem is related to your mods. By supplying a warranty at the time of sale they've agreed to diagnose such issues. Make sure they know that.

[Tsensational]

I'm sure they do but i dont wanna go anymore. So much angry has been going on recently.

[snoeclipse]

Make sure you have no air leaks in your CAI, expec between your MAF sensor and the engine.

When you put the headers on what did you do with the O2 sensor?

How many miles? Ever have the tranny serviced (fluid, filter, etc)? If you get a tranny service, make sure you go to a place that will do a pan drop and full flush. You really want to get the old fluid out of the torque converter and cooler lines. After a flush it might be a good time to go with a full synth tranny fluid like RP or Amsoil. NO Chevy or Ford tranny fluids!! Chrysler ATF+4 is ok (Valvoline makes it now too). Both Amsoil and RP meet/exceed Mitsu SP-III requirements for heavy duty use.

"Only when hot" tells me to check the air intake and transmission first. Then exhaust and electrical. If the car isn't throwing a SES light and codes, any electrical troubleshooting would be at the battery and alternator. You could clean up the +- battery terminals just for the sake of it.

[Tsensational]

CAI and MAF have been perfect. No dust inside, no air leak or anything. It was the first thing I checked.

The headers were done by RRE since they wanted to test the fitment (I prototype tried them on) so everything should be fine.

At 20k miles, I havnt done any transmission flushes yet. But I'll check the oil today.

As for alternator, the problem has been there for awhile so shouldn't the battery be dead? I'll do the running car without battery test while running idle.

[Tsensational]

Alternator is working fine. Disconnected battery while idling car for awhile and no changes happened. Transmission fluid looks decently clean so lets make a list of what its not or shouldnt be.

CAI: No, otherwise there would be at least trace amounts of dust in it right?
Alternator/Battery: Nope, electronics have been running fine, disconnecting battery while car runs still keeps car alive.
Sensors: Shouldn't be because no check engine lights
Fuel Injectors: Used cleaner. That should rule that out.
Belts and pulleys: Everything is tense and spinning smoothly so I doubt that's it.


I've gotta say, its probably something in the transmission because:
"Sloppy" Automatic transmission shifts
Super shudder when braking
also lots of power loss

HOWEVER! Transmission fluids exactly perfect in the correct color.


But I dont have enough money to get the entire new automatic transaxle.


Learning is fun.

[snoeclipse]

a pan drop, flush, new filter, synth refill shouldn't cost you more than $125- Way cheaper than $3000-3500 for a rebuilt tranny and installation.