***you can physically see my phone shaking on the mount due to the cars stuttering!!***
Here's another video. Skip to 0:40 if you don't care for the random talk. I went ahead and ordered a MSD coil pack with MSD wires and a set of colder plugs. Assuming they get here this weekend I will be putting on a few things. These spark plugs almost look OEM. If that's the case, then they're 98k miles old! What is the spark plug code for OEM plugs on an 05 R53? Anyone know?

1. I'm going to put in the new plugs with coil and wires.
2. Spray down both MAP sensors with cleaner if my problem persists (what type of cleaner?)
3. Put on new Alta silicone couplers (I'm going to do this regardless if it's fixed)
4. Clean out the intercooler with 2 bottles of brake cleaner.



I'll post up the results this weekend. Thanks everyone for being super patient with me, means alot.

 

If none of that fixes the problm (I'm guessing it will)
........I'm almost betting that it could be a broken spring in the Bypass valve. That's what was wrong with mine...but I had different symptoms. My car just didn't have any power because it wasn't making any boost at all.

The only thing I can think of is that maybe the spring in your BPV is broken, and when you are hard on the gas.....the buterfly valve inside the BPV is just bouncing around between open and closed.....causing that stuttering effect. You said that when you reach down and pull the arm on teh BPV open....when you let go it snaps shut right? When the spring in mine was broken...it would close a little, but not snap shut with any real authority.

 

It snaps right on shut. It is pretty tough to move.

 

I've been following this since the start... I'm having similar problems but after seeing the video it appears we are having different issues. Yesterday I put on my new supercharger intake pipe and Alta intercooler boots.. I have a little more install work to have the front bumper and everything put back together and I'll do some runs today and see what happens! again my issue is when i'm in 3rd 4th 5th or 6th gear and stomp the gas right before 3000 RPM it flares to 4000 RPM then hovers on 4000 for a second or two then catches itself again and starts to pull but with very very little power.

 

Hey ralph

I figured as much that youd be following the thread. You should try to record a video if the problem persists!

 

yeah if i get everything back together and still have the problem I will post a video!

 

got everything on and then reset the ECU.

looks like i fixed the problem. i put on a new coil pack, leads and some spark plugs. idles smoother for sure and that stuttering appears to be gone. time will tell. thanks to everyone who has been patient with me and this thread.

 

I finally found a thread that matches my issue! I have a 2006 R53 with a CAI (Dave.f modification.) I recently had a WMW 17% pulley kit installed (pulley, belt and plugs.) After picking up my car from the shop, I immediately began to experience the same SC stutter under 3k RPMs at WOT. Once I hit 3k, my car takes off! WMW suggested that I check the coil pack and wires for corrosion and damage, but all was clear. I have read in a few other post that the replacement of these components would solve the issue, but I wanted solid feedback before making the purchase. Can any of you provide a testimony, or a theoretical explanation how the replacement of these parts can resolve the problem?

 

Can you post a video showing what it's doing?

 

My car does the exact same thing as shown in qolor's video above. You can hear the SC repeatedly rev up and down upon acceleration. You'll see it occur 3 times while watching the video: at 12-14, 27-28 and at 45-47 seconds.

 

I'd take to the considerations in this thread then.

Spark plugs, wires, etc.
If not, move on to the BPV.

 

Don't just throw parts at your car. The OEM plug wires are very good, better than aftermarket and can be tested with an ohm meter to measure resistance. The BPV is easy to check with a handheld vacuum pump. There is a small vacuum line on the BPV that you disconnect from the diaphragm, attach the pump, and pump it up to 20 lbs. It should open and hold pressure. The OEM coil is also better than aftermarket and I have seen this exact problem caused by MSD's and Screamin Demons.

 

Plug wires.

 

Thanks for the replies. One thing I forgot to mention, the coil pack and wires are original with 116k miles. Could this be an issue, even if there is no signs of corrosion or damage?

 

I don't know if I would change out the coil pack....I don't think they really get weak, they either work or they don't. But as far as the wires, when they get old they can build up resistance and cause issues.

What about the plugs?

I would definitely put a fresh set of plug wires on it....easy and fast thing to try.

 

Thanks IQRaceworks. I'd like to avoid blindly throwing money into this issue, but I think your suggestion is on point. I'm going to replace the wires. I've found a couple of other threads that document a resolution to what sounds to be the same problem. I'll let everybody know the results. BTW, the plugs were replaced with cooler running ones with the installation of the pulley.

 

How many miles on your car? Might want to look at your fuel filter/pump if it looks like its running lean.

 

Hey guys, OP here.

I actually solved my problem by replacing the coil pack, leads and plugs.

I later (6 months after) took the leads off of my coil pack. #3 had corrosion on the metal. Could have saved myself 70 dollars over buying this MSD pack.

To the man asking about his car, I would say, just do the leads and plugs as a preventative maintenance anyways. If it fixes your problems, congratulations! :p Also, the fuel pump filter is annoying, and likewise the fuel pump. I am doubtful it is the pump. Usually, like starters, they either work or they don't (from my experience) and beating it with a stick... (???) often temporarily fixes the problem.

Many people complain about a hesitation after replacing their plugs with a colder range and not replacing the plug wires. Our coilpacks are strong, wires, not so much.

 

Again, thanks for the replies! Upon closer inspection of the wires, I noticed that they have no markings on them at all, which leads me to believe that they may have been replaced with ones that are inferior to OEM at some point. New wires have been ordered. I'll keep you posted.

 

-2003 R53 with 180,000 Miles-

I have a simular issue and I am hoping to find answers. I have had this issue since I purchased the car last year and have replaced several parts with no resolution.

at 2300-3000 RPM there is a significant power loss. you accelerate up in speed and when you hit 2300 RPM theres a restriction of power and then when i reach 3000 RPM the restriction of power is gone and I accelerate as normal.

Also another issue that hasn’t been resolved which may or may not relate to the acceleration problem is on idle. Intermediately happens when I stop at a stop light. It starts to sputter as if its struggling to stay running. it does not matter if the AC is on or off. I live in florida so it is 90’ everyday but the car shouldn’t have these issues.

I have no check engine lights on and no other idea of what it might be??

Here is everything that has been done to the car:

Detroit tuned Bypass valve
Spark plugs
Plug wires
Map Sensors
WMW 15% supercharger pulley
Timing chain tensioner
supercharger Belt Tensioner
Supercharger inlet tube
ATI supercharger damper crank pulley
Megan racing EZ coil overs
Power steering pump
Oil pan and seal
15% supercharger belt
DDM works air intake
DDM works intercooler boots
M7 Oil Catch Can Kit

The next attempt is walnut blasting the intake valves.

 

You don't need to do a walnut blast. The R53 is a different motor than the R56. The R56 needs walnut blasting because they are direct injected and fuel never gets to the valves and cleans the deposits off of them. This isn't a problem with the R53. Just use good gas, 91-93 octane top tier fuel. Check all your lines and intercooler boots for vacuum leaks. OEM plugs and wires are good to have, but check the terminals on the coil for corrosion and if there is any you can sand or brush it off.

 

Thank you for responding.
I definitely use 93 octane at all times. There is no corrosion on the coils and there are no vacuum leaks. Everyone says to check for those two concerns as well but that does not seem to be the cause. This has been an ongoing issue since I purchased the car last year. Hoping to find other ideas of what might be the problem. :(

 

Aftermarket coil and wires?

 

When my R53 did this, I swapped all the ignition components one at a time.

Spark plugs: made no real difference
Wires: smoothed out idle, slightly less hesitation between 2-3k but still had the problem.
Ignition coil: totally resolved all problems

For what it's worth, I used NAPA parts with the exception of plugs (NGK's) and I have put some miles on it (about 4k, daily driven) with no problems yet.

I checked the corrosion on the old coil and all that, cleaned it up and it didn't change anything. It might just be that time for coil.

 

I received the wires in the mail today and installed them. Voila, problem's solved! To IQRaceworks and qolor, thanks you profusely for your recommendations. I have power all through the RPM range in all gears, without stutter.

In review of my service records, I realized that the coil pack and wires were replaced in May 2013 to correct what was believed to be some kind of misfire. I'm left to assume that the after market wires installed, only 2 years old now, are inferior to handle the airflow produced by the 17% pulley. I'm no mechanic so please correct me if my assumption is wrong.