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Discussion Starter #1 (Edited)
What would cause a rough idle while in Drive with a normal RPM reading? It is a near perfect idle while in park, but while in Drive and my foot on the brake, it shakes pretty good. The RPMs is steady and it doesn't throw any codes. When I drive everything is good and I get 20miles per gallon in the city. I have new NGK plugs, new ignition coils, cleaned the throttle body, new drive belt and tensioner. No weird noises, no detected vaccum leaks. 2007 tech 174kmiles
 

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Check your vacuum hoses.
It could be the tiniest hairline crack on the end of a hose.

This happened to me once.
If you find it, it may be as simple as trimming the bad end, refitting it (putting it back on), and voila done. Problem solved.

Hope this helps.

All the best!
 

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What would cause a rough idle while in Drive with a normal RPM reading?
Yep, I have the same mileage and in drive with brake applied the vibration is very much there. No codes and no issues with my car - it's maintained perfectly.

It could be many things, but I'm hoping it's just shot engine/transmission mounts. At this mileage it's expected.

Could be the torque converter, though. Which would cost about half of the current vehicle value to fix :) So I hope it's not it.

Could also be counterfeit NGKs I got off eBay five years ago. I'm replacing my spark plugs later this year to OEM Densos, I'll keep this forum posted if it resolves the issue.
 

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When you say "rough idle", I am assuming you are referring to the performance of the engine.

Or, are you referring to a rough ride as in possible transmission or drive train issue?

"Rough idle" itself denotes engine performance. Which can be caused by the most minor of vacuum leaks as described in my post earlier in this thread.
 

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Discussion Starter #5
When you say "rough idle", I am assuming you are referring to the performance of the engine.
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Or, are you referring to a rough ride as in possible transmission or drive train issue?

"Rough idle" itself denotes engine performance. Which can be caused by the most minor of vacuum leaks as described in my post earlier in this thread.
When sitting still and brake applied and in drive, I can feel the engine rotating. I did buy some cheap after market motor mounts and I have replaced the front mount already as it was broken with an OEM mount. I'm going to replace the other 3 with OEM mounts (rear) and two anchors and see what it feels like after that. Once I hit the gas, its very smooth and no shaking. Only when the foot is not on the gas is when I can feel it. Its not as noticeable in park but you can see the engine moving while looking at it with the hood raised. I removed the vaccum hoses and didn't see anything and placed them back on. The throttle body has been cleaned, injectors cleaned during the same process, new store bought NGK plugs and new coils.
 

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When sitting still and brake applied and in drive, I can feel the engine rotating. Once I hit the gas, its very smooth and no shaking. Only when the foot is not on the gas is when I can feel it.
Same here.

Its not as noticeable in park but you can see the engine moving while looking at it with the hood raised.
Now that I haven't seen, but I didn't check with anyone sitting in the driver's seat and pressing the brake in D. I'll do that.
 

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Discussion Starter #7
Hello I fixed my rough idle problem. There were two things I needed to do. Clean out the EGR Port. Replace motor mount on the belt side of the engine. All is smooth as butter now. I cleaned out the EGR port and I replaced the upper gasket and replaced the EGR pipe. I had a cheap after market motor mount and it was broken anyways, so I went OEM on the new motor mount.
 
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