Extremely rough idle ONLY in gear and at a stop 05' LGT 5EAT

I recently bought a stock 05' LGT 5EAT with 120k miles. It is running extremely rough only at idle in Drive and at a stop. Car shakes and vibrates a lot, but as soon as I let off brake,start rolling or shift into Neutral at a stop everything is back to normal smooth idle. RPMs do not look like they are jumping around when it is shaking. Dealer spent 4hrs inspecting it, and they basically regapped my new NGK plugs and reset Cyl 4 MisFire CEL. CEL has not come back on for a good 400miles of driving since they did that.

I also have a Tactrix cable is there something specific i should be logging for?

Here is a RomRaider screen shot I took after driving around for 1.5hrs last night, and a Learning View from before I started driving.

What should I be looking for next? My plan so far is swapping all 4 coil packs from my 08' LGT and if that doesnt fix it. Fuel Injector cleaning service, compression/leakdown test.

Originally Posted by Bbc84

I recently bought a stock 05' LGT 5EAT with 120k miles. It is running extremely rough only at idle in Drive and at a stop. Car shakes and vibrates a lot, but as soon as I let off brake,start rolling or shift into Neutral at a stop everything is back to normal smooth idle. RPMs do not look like they are jumping around when it is shaking. Dealer spent 4hrs inspecting it, and they basically regapped my new NGK plugs and reset Cyl 4 MisFire CEL. CEL has not come back on for a good 400miles of driving since they did that.

I also have a Tactrix cable is there something specific i should be logging for?

Here is a RomRaider screen shot I took after driving around for 1.5hrs last night, and a Learning View from before I started driving.

What should I be looking for next? My plan so far is swapping all 4 coil packs from my 08' LGT and if that doesnt fix it. Fuel Injector cleaning service, compression/leakdown test.

My 05 5EAT has been doing almost the exact same thing. Rough while stopped. In gear or not. Car drives perfectly with any throttle input. 108K on the clock. New spark plugs. Gapped @ factory spec.

Transmission mounts ok? Not torn?

sounds like a bad trans or motor mount to me. we have the same issue on our odyssey, front motor mount goes bad and you can feel vibration when in gear stopped, as soon as you take off it goes away.

Ill check the trans mount next. I was researching on other Subaru forums and looks like it might also be caused by the cheap Advance Auto front CV axle I had replaced with. For what ever reason cheap axles caused lots of noise/vibration to be transmitted. And that was the first thing I replaced the day after I bought the car.

Still doesnt explain the misfire that happened before axle replacement and afterwards. But since it hasnt come back after dealer regapped plugs ill wait before I mess with injectors or compression test.

Anyway to visually inspect broken motor mounts?

Bbc84,
WOW!! you drove around 1.5 hours and only went 37mph?? OK I had to say that. Now I ask, Have you cleaned your MAF sensor?, Reset computer after cleaning MAF, let it learn new curves for a bit, check air filter? Judging from your post count, you know the basics, remember, it's a different car, what you have done on the "Other" car has not been done on this one, (I know this from personal experience, having 2 '05 LGT's), kind of a mind set thing, I now use log books, for issues and fixes for each car. I'm not flaming you at all, just trying to help, cause it happened to me!

R/Mac

Yup cleaned MAF sensor with that MAF spray, new air filter, changed plugs to new NGK's. visually checked vacuum lines, and especially the Blue T one under the TMIC.

For now I guess I will sit and wait to see if the misfire comes back. Running some Redline Fuel Injector cleaner for the 2nd time in 1k miles to see if that will help as well.

if you need any parts just hit me up, i have oem fuel injectors to 5eat mounts for trans...

it could be that you have a bad injector and thats whats causing the misfire. but I'm not too familiar with this part of the motor so i may be wrong. hope you figure it out

Yea if it misfires again, i plan on taking all the injectors out and to a shop to clean them and flow test them.

Mine does the exact same thing that you described. I fixed the low rpm issue by cleaning and "straightening" the MAF sensor and installing it nice and tight. I still have a misfire, so I will take it to a tuning place and have them check it out. But...I'm glad I got rid of my low rpm issue.

Mine does it too with a 5MT. Will try cleaning MAF... then I need to reset Cobb stage 1 flash?

You new guy's don't know about the o rings between the intake manifold and TGV's. There are known to leak when it's cold out and cause idle issues.

When you see the new ones next to the old ones, you'll understand.

Not saying that's your issues, but, just keep them in mind.

Anyone know what the idle speed is suppose to be in gear on a 5EAT?

I'm guessing 750-850rpm

750 in neutral and somewhere around 700/high 600's in Drive for autos. your fuel trim A is high(leaning out) which i suspect is an unmetered air vaccum leak or the airbox isnt seated and sealed properly.