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Discussion Starter · #1 ·
With the AC off sometimes I hear a little stumble from the engine when sitting at a light for a while. It's as if the RPMs dip below 700 for a second and jump up to 800, settling back at 750. All this happens in a second of so. Just changed the plugs with OEM 2 days ago and this issue remains. Plugs were gapped at .028.

I also assumed it was when the cooling fan was kicking in, draining power for a second to start itself up, but when listening outside the car yesterday I was able to determine that when the shudder happens the fan is not the cause...

Does anyone know what this could be? It's very minor but my 2008 2.5T didn't do this so I am assuming something is wrong here
 

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I had the same thing on my 850R. It got progressively worse, until I swapped out my vacuum lines with silicone lines.
 

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My car does this now because I installed the upper engine mount and strut bar conversion kit. Since the engine can't move as much it wants to stall almost. Now this probably isn't why yours does this but I thought I would put my experience into this thread.
 

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Discussion Starter · #4 ·
I had the same thing on my 850R. It got progressively worse, until I swapped out my vacuum lines with silicone lines.
I have silicone blue and yellow vac lines, the red and CBV was too much of a hassle for me to do until I get my Viva CBV.

Did you notice any tears in any specific lines that was causing this?
 

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Hmm mine does the same thing and has since I bought it 3 yrs ago. All my vac lines are silicon, I have replaced the fuel pump the PEM and the FPS, spark plugs, coils with IPD HD units. I also have a strut bar conversion that was on the car when I bought it. I also have the IPD upper engine mount and lower trans mount. Any ideas?
 

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Mine does this, always has. All my lines are new. I gave up on it years ago.
 

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Mine was more of a 'miss' but seemed to be corrected by a full tuneup.
 

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A faulty FPS could also be a cause of this.
+1

For a little while now my car's been doing the same thing. On top of that, for about a week, my car had a CEL for the fuel pressure sensor, faulty signal.

When I swap it out on Saturday, I'll let you know how it goes.
 

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Mine does this, always has. All my lines are new. I gave up on it years ago.
Yea I just wrote it off as normal Car runs the best it has since I bought it except for the slight stumble that mostly happens when warming it up. Do we all have MY 04 R's that do this?
 

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Discussion Starter · #11 ·
I plan on cleaning the throttle body when I do my FMIC install this weekend (which I am making a guide-video of by the way for anyone who is interested), i'll see if this helps any, but honestly this issue isn't a big enough of a deal to get me worried enough to start replacing things like the FPS.

But if it starts happening more often and the throttle body cleaning doesn't help then i'll definitely check into the FPS and everything else suggested.
 

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I plan on cleaning the throttle body when I do my FMIC install this weekend (which I am making a guide-video of by the way for anyone who is interested),
your the man. So interested.
 

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+1

For a little while now my car's been doing the same thing. On top of that, for about a week, my car had a CEL for the fuel pressure sensor, faulty signal.

When I swap it out on Saturday, I'll let you know how it goes.
Interested to hear results. How easy is the FPS swap?
 

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FPS is easy to change out, search for install threads.

I had to replace mine about 18 months ago due to failure, used the Land Rover part #. I still have the same issue at idle, almost seems worse WITH the A/C on. I also have upper engine mount/strut bar mods, but I'm surprised that would cause this stumbling issue. Interested to hear your results as well...
 

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Interested to hear results. How easy is the FPS swap?
Very easy, you'll just make a bit of a mess with the gas. Don't expect to go anywhere immediately after you finish.

After only driving tonight, my issues appear to be gone. To be specific, I have the solid engine stabilizer bar mounts and poly upper and lower mounts.

I live on a fairly steep hill, and every time I leave with the engine cold, the car almost struggles to accelerate up the hill. Today it did not. I also felt no stumbling at any point while cruising around.

After the weekend I'm sure I'll have a better idea.
 

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Mine does this too but its minor... Till it does it with the cutout open... Thats when I really hear it but honestly it still doesint really bother me all that much anymore.. Kinda got use to it now. Thought it was my car changing to compensate for the downpipe just running open.

Sent from my Epic 4G Touch!
 
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