Rough Idle with possible solutions. Thoughts?

[Vengence]

2008 PT LX Model. For some time now, it didnt bother me before but now it is but, It idles a bit rough. I have a few ideas/possible solutions to this but I want to get opinions before I start doing these ideas.

Idea Number 1- Cleaning out the Throttle Body and IAC. Mechanic says to just replace them if they are the cause but what could the harm be for just cleaning them out? Not spraying cleaner directly in there and just spraying on a rag and cleaning it out.

Idea number 2- Possibility that the Top and lower Mounts are not alligned. I had both replaced, 1 after I bought it which was fixed complimentary by the seller/dealer and the Top replaced about 6 months later. Where I believe the issues started. I never knew that alignment of motor mounts was possible until recently and explains a lot of what is happening.

In short on the mounts is this. Loosen the Top and Lower Mounts, Jack up the engine to rotate it a bit and align it properly. How to do this is fairly simple. In the picture I uploaded, You measure in Millimeters between the 2 red dots in the picture. So, with both Mounts loosened, the engine would sit between 122-124mm. You jack up the engine until the distance between those 2 red dots is 119mm and you tighten both mounts down again. So, you use the hole by the mount where the fuel line clip that holds the fuel line in place as one point and the middle of the bolt with the red dot as the other point. Once it is at 119mm, 90% of vibration issues are fixed. According to the video. This has worked for most but not others. Others mentioned it was Throttle Body and IAC, some the Center Mount which mine is okay, and some had misfires which mine is not doing.

What are your guys thoughts? Anything else I should look into as well?

Little Background- New Spark Plugs, New Wires, New Valves, New Timing Belt/Water pump, Engine and Head Gasket Resurfaced 1 year ago.

[wwpptc]

Originally Posted by Vengence

2008 PT LX Model. For some time now, it didnt bother me before but now it is but, It idles a bit rough. I have a few ideas/possible solutions to this but I want to get opinions before I start doing these ideas.

Idea Number 1- Cleaning out the Throttle Body and IAC. Mechanic says to just replace them if they are the cause but what could the harm be for just cleaning them out? Not spraying cleaner directly in there and just spraying on a rag and cleaning it out.

Idea number 2- Possibility that the Top and lower Mounts are not alligned. I had both replaced, 1 after I bought it which was fixed complimentary by the seller/dealer and the Top replaced about 6 months later. Where I believe the issues started. I never knew that alignment of motor mounts was possible until recently and explains a lot of what is happening.

In short on the mounts is this. Loosen the Top and Lower Mounts, Jack up the engine to rotate it a bit and align it properly. How to do this is fairly simple. In the picture I uploaded, You measure in Millimeters between the 2 red dots in the picture. So, with both Mounts loosened, the engine would sit between 122-124mm. You jack up the engine until the distance between those 2 red dots is 119mm and you tighten both mounts down again. So, you use the hole by the mount where the fuel line clip that holds the fuel line in place as one point and the middle of the bolt with the red dot as the other point. Once it is at 119mm, 90% of vibration issues are fixed. According to the video. This has worked for most but not others. Others mentioned it was Throttle Body and IAC, some the Center Mount which mine is okay, and some had misfires which mine is not doing.

What are your guys thoughts? Anything else I should look into as well?

Little Background- New Spark Plugs, New Wires, New Valves, New Timing Belt/Water pump, Engine and Head Gasket Resurfaced 1 year ago.

Your pic above was a little hard to decipher. I tuned it up.



Jerry

[Vengence]

Thanks. Not too good with picture editing and what not.

[rsrocket1]

If the holes are not spaced at 119mm, definitely get the spacing done, it should take you about 20 minutes. The biggest hassle is removing the plastic splash guard, not the alignment

You might also check your PCV valve and the hose going to it. If the hose is split on the end or cracked or the PCV doesn't freely rattle when you remove it and shake it, replace it/them. It's super easy to get to and the parts are cheap.

[Vengence]

Update-

Throttle Body is clean.
IAC good.

Mount Allignment is ****ed. That will be dealt with in a couple weeks after I know for sure the Snow is gone and switch the tires and get an allignment. The mounts measurement wise is 124-125mm between the 2 spaces. So that will DEFINITELY have to be taken care of asap. I will look into the PCV Valve as well.

[ptcruisersteve]

Originally Posted by Vengence

Update-

Throttle Body is clean.
IAC good.

Mount Allignment is ****ed. That will be dealt with in a couple weeks after I know for sure the Snow is gone and switch the tires and get an allignment. The mounts measurement wise is 124-125mm between the 2 spaces. So that will DEFINITELY have to be taken care of asap. I will look into the PCV Valve as well.

On my Pt Cruiser there was a plastic fitting for holding a hose that I was suppose to measure the the hole from so you really need to do your homework to make sure the measuring is done correctly and check to verify the location of the reference holes.

[rckstein]

Originally Posted by ptcruisersteve

On my Pt Cruiser there was a plastic fitting for holding a hose that I was suppose to measure the the hole from so you really need to do your homework to make sure the measuring is done correctly and check to verify the location of the reference holes.

Steve, did you read the OP's original post?

Originally Posted by Vengence

2008 PT LX Model. For some time now, it didnt bother me before but now it is but, It idles a bit rough. I have a few ideas/possible solutions to this but I want to get opinions before I start doing these ideas.

Idea Number 1- Cleaning out the Throttle Body and IAC. Mechanic says to just replace them if they are the cause but what could the harm be for just cleaning them out? Not spraying cleaner directly in there and just spraying on a rag and cleaning it out.

Idea number 2- Possibility that the Top and lower Mounts are not alligned. I had both replaced, 1 after I bought it which was fixed complimentary by the seller/dealer and the Top replaced about 6 months later. Where I believe the issues started. I never knew that alignment of motor mounts was possible until recently and explains a lot of what is happening.

In short on the mounts is this. Loosen the Top and Lower Mounts, Jack up the engine to rotate it a bit and align it properly. How to do this is fairly simple. In the picture I uploaded, You measure in Millimeters between the 2 red dots in the picture. So, with both Mounts loosened, the engine would sit between 122-124mm. You jack up the engine until the distance between those 2 red dots is 119mm and you tighten both mounts down again. So, you use the hole by the mount where the fuel line clip that holds the fuel line in place as one point and the middle of the bolt with the red dot as the other point. Once it is at 119mm, 90% of vibration issues are fixed. According to the video. This has worked for most but not others. Others mentioned it was Throttle Body and IAC, some the Center Mount which mine is okay, and some had misfires which mine is not doing.

What are your guys thoughts? Anything else I should look into as well?

Little Background- New Spark Plugs, New Wires, New Valves, New Timing Belt/Water pump, Engine and Head Gasket Resurfaced 1 year ago.

He has the correct measuring points, which can be seen in the photo enhanced by wwpptc.




But just in case, this is from the Chrysler Service Manual:

[rckstein]

Originally Posted by Vengence

Update-

Throttle Body is clean.
IAC good.

Mount Allignment is ****ed. That will be dealt with in a couple weeks after I know for sure the Snow is gone and switch the tires and get an allignment. The mounts measurement wise is 124-125mm between the 2 spaces. So that will DEFINITELY have to be taken care of asap. I will look into the PCV Valve as well.

The 119mm measurement is while the jack is still supporting the engine. Once you remove the jack the measurement might change a little depending on how worn out the upper and lower torque struts may be.

I've sent you a PM with a link to download a copy of Chrysler Service Manual from my dropbox. Page 9-2105 starts the procedure about the upper and lower torque struts.

[ptcruisersteve]

Originally Posted by rckstein

Steve, did you read the OP's original post?



He has the correct measuring points, which can be seen in the photo enhanced by wwpptc.




But just in case, this is from the Chrysler Service Manual:

I sure did and just letting other members know that sometimes there is a plastic holder in that hole and this has been posted in my own project replacing the upper and lower mounts.

[rckstein]

Originally Posted by ptcruisersteve

I sure did and just letting other members know that sometimes there is a plastic holder in that hole and this has been posted in my own project replacing the upper and lower mounts.

If your PT is missing this clip, you should look at replacing it as it does serve a purpose supporting the fuel line