P0505: idle control system malfunction?
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From: Keller
clk63, cls55, ml63, (w210) E55
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From: A to the Z (the state)
'06 E55
What could be happening is you're getting unmetered air in. I had this problem and it turned out to be a air leak between the PipeLine that the Throttle body sits on and the supercharger. Some brake cleaner was sprayed in the area of suspect and the motor stalled, pin pointing the problem and the leak.
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Joined: Apr 2013
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2006 cls 55 amg
WHAT UP FELLAS....I HAVE A 2006 CLS 55 AMG ...WITH KLEEMAN HEADERS,82 MM THROTTLE BODY,INJECTORS, EUROCHARGED ECU /TCU TUNE, EUROCHARGED H/E AND PUMP.....I AM ALSO GETTING THE 505 CODE AND MY AIR/ FUEL GETS REALLY RICH ...I HAVE HAD THE CAR SMOKE TESTED AND NO LEAKS...IM HELLA FRUSTRATED ALL THIS MONEY FOR THE CAR TO ACT UP...ANY HELP OR ADVICE ON WHAT TO DO TO FIX IT.....THANKS
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From: Clearwater Beach, Florida
2016 Cls63s AMG
we just put my buddies s/c back together and installed the 82mm OEM tb and no CEL.. we just have not pluged the snoute hole yet and the idle is a little rough but other than that she fired right up and stuff
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2006 cls 55 amg
I also have an OEM throttle body..mine fires up just throws the code when u drive it and my air / fuel at wide open throttle is 10.0...
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From: Fairfax,VA
06 E55
Okay, I just joined the club. Got both 505 and 507 now, really doubt that there is a vac leak cause tb was installed by very reputable guy. Did anyone find a solution for this problem?
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Joined: Apr 2013
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From: Sarasota, Florida
2004 E55 AMG
I know this is an old thread but...
I had a similar P0505 / P0507 after doing the throttle body grind and it turned out to be the fact that I didn't properly torque the surge tanks which I removed and painted at the same time.
I thought it might help someone else to know this.
FYI, Shardul says that proper torque is 20Nm which is about 14.76 foot pounds.
Be careful not to snap, and tighten in a criss-cross pattern.
D-
I thought it might help someone else to know this.
FYI, Shardul says that proper torque is 20Nm which is about 14.76 foot pounds.
Be careful not to snap, and tighten in a criss-cross pattern.
D-
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car
I just got it too. I'm stock too. I'm going to spray brake cleaner on it while the car is running. Hope I find it.
EDIT:
I was getting the p0505 code only and some times while driving giving me the flashing gas light, with the red screen saying to tighten fuel cap. Also had a rough idle here and there.
EDIT:
I was getting the p0505 code only and some times while driving giving me the flashing gas light, with the red screen saying to tighten fuel cap. Also had a rough idle here and there.
Last edited by garagequeen; May 18, 2016 at 12:09 AM.
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car
So I didn't pull my blower or TB. BUT I did pull my valve covers and the back bolt(driverside) for the valve cover holds that hose on, when I first put the valve covers back on I didn't hook that hose bracket back to the valve cover. That made it blow out(I didn't know that at the time), and I got the code. I put the bolt in thinking the hose was in the blower. But no.
Hope this helps someone.
Hope this helps someone.
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Joined: Feb 2008
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Did someone ever get this sorted out with their 82 mm M273 engine TB mod?
I used brake cleaner to go on the infamous leak hunt and the only place where the engine stutters is if I spray it directly at the Y-piece where it connects to the TB. But since that is before the TB it shouldn't be the cause to throw the P0505/P20A2 (in DAS).
I also get the P202B-002 idle speed control implausible short to ground and P2007-008 Pressure Sensor B28 Signal implausible on occasion but I think that is just a side effect.
The purge line (small little aluminum pipe) is all the way in the snout. The grommet is new. The breather hoses are both new.
I tried two different TBs to rule a bad one out.
I'm running out of ideas.
I used brake cleaner to go on the infamous leak hunt and the only place where the engine stutters is if I spray it directly at the Y-piece where it connects to the TB. But since that is before the TB it shouldn't be the cause to throw the P0505/P20A2 (in DAS).
I also get the P202B-002 idle speed control implausible short to ground and P2007-008 Pressure Sensor B28 Signal implausible on occasion but I think that is just a side effect.
The purge line (small little aluminum pipe) is all the way in the snout. The grommet is new. The breather hoses are both new.
I tried two different TBs to rule a bad one out.
I'm running out of ideas.
Super Member
Joined: Jan 2016
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2004 E55
Did someone ever get this sorted out with their 82 mm M273 engine TB mod?
I used brake cleaner to go on the infamous leak hunt and the only place where the engine stutters is if I spray it directly at the Y-piece where it connects to the TB. But since that is before the TB it shouldn't be the cause to throw the P0505/P20A2 (in DAS).
I also get the P202B-002 idle speed control implausible short to ground and P2007-008 Pressure Sensor B28 Signal implausible on occasion but I think that is just a side effect.
The purge line (small little aluminum pipe) is all the way in the snout. The grommet is new. The breather hoses are both new.
I tried two different TBs to rule a bad one out.
I'm running out of ideas.
I used brake cleaner to go on the infamous leak hunt and the only place where the engine stutters is if I spray it directly at the Y-piece where it connects to the TB. But since that is before the TB it shouldn't be the cause to throw the P0505/P20A2 (in DAS).
I also get the P202B-002 idle speed control implausible short to ground and P2007-008 Pressure Sensor B28 Signal implausible on occasion but I think that is just a side effect.
The purge line (small little aluminum pipe) is all the way in the snout. The grommet is new. The breather hoses are both new.
I tried two different TBs to rule a bad one out.
I'm running out of ideas.
Pressurize the system with 18psi and cap off what should flow air while running and look for leaks. When I did this it revealed a huge vacuum leak at due to an aging and failing brake booster plug on back of the snout. How I tested bc I don't have a smoke machine was similar to my turbo car days:
seeMake sure compressor is full (30gallon-130psi) adjust regulator to 18-20psi. Close garage. Turn off any sound so you can isolate where any leak could be coming from. Take off surge tanks. Cap off rubber coupling to surge tanks. Silicone coupler used with T-bolt clamps to cap throttle body. Unplug line on bottom of throttle body and use a 5/8" hose with a clamp to keep it on the throttle body. Cap end of 5/8" hose. Unplug SAI vacuum port feed line next to the black vacuum port already capped on snout. That will be your pressure input line. Use an inline pressure gauge with a vacuum T showing pressure on the line. Charge the system up to 18PSI and listen and wait. If it's bleeding air you will hear it and can judge where the sound is coming from. Gauge will also show pressure drop
I had no clue how bad my brake booster plug was leaking until this test and was going nuts trying to figure out why my idle became rough.
Bunch of stuff on order now for the reseal, bearing re-lube, wiring continuity verification and re-insulation.
"If you take it apart put it back better than you found it"
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Thank you.
I replaced the following when I did the mod:
- gasket between engine and Kompressor
- gasket between Kompressor and surge tanks
- gasket between Kompressor and snout
- gasket between Kompressor and intercooler
- grommet for the Aluminium pipe from the gas tank vacuum line
- breather hose from TB to valve covers
- vacuum hose from valve cover to Y-pipe
Now I'm gonna take it all out and replace the rubber hose type seal on the bypass flap and the pressure sensor and hope this is it.
I replaced the following when I did the mod:
- gasket between engine and Kompressor
- gasket between Kompressor and surge tanks
- gasket between Kompressor and snout
- gasket between Kompressor and intercooler
- grommet for the Aluminium pipe from the gas tank vacuum line
- breather hose from TB to valve covers
- vacuum hose from valve cover to Y-pipe
Now I'm gonna take it all out and replace the rubber hose type seal on the bypass flap and the pressure sensor and hope this is it.
Last edited by Mackhack; Aug 12, 2017 at 12:33 PM.
Super Member
Joined: Jan 2016
Posts: 599
Likes: 120
2004 E55
Thank you.
I replaced the following when I did the mod:
- gasket between engine and Kompressor
- gasket between Kompressor and surge tanks
- gasket between Kompressor and snout
- gasket between Kompressor and intercooler
- grommet for the Aluminium pipwmfor the gas tank vacuum line
- breather hose from TB to valve covers
- vacuum hose from valve cover to Y-pipe
Now I'm gonna take it all out and replace the rubber hose type seal on the bypass flap and the pressure sensor and hope this is it.
I replaced the following when I did the mod:
- gasket between engine and Kompressor
- gasket between Kompressor and surge tanks
- gasket between Kompressor and snout
- gasket between Kompressor and intercooler
- grommet for the Aluminium pipwmfor the gas tank vacuum line
- breather hose from TB to valve covers
- vacuum hose from valve cover to Y-pipe
Now I'm gonna take it all out and replace the rubber hose type seal on the bypass flap and the pressure sensor and hope this is it.
My booster plug appeared fine and didnt display any symptoms of failing. Once I added pressure it became glaringly evident it was leaking and causing my idle issue. I ripped the plug out and capped it with a tapered rubber plug with a big bolt to expand it and seal tightly until this weekend/next week when the charger will come off again.
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Joined: Feb 2008
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Sounds like you hit most the hard parts, yes the rubber ring that seals the bypass TB could the issue. I personally would pressure test it first and see if you can find the leak causing your idle to drop... its gonna be pretty glaring when you add some PSI and it will hiss at you. Perhaps you don't have to rip the charger off without a real fault revealed under the charger.
My booster plug appeared fine and didnt display any symptoms of failing. Once I added pressure it became glaringly evident it was leaking and causing my idle issue. I ripped the plug out and capped it with a tapered rubber plug with a big bolt to expand it and seal tightly until this weekend/next week when the charger will come off again.
My booster plug appeared fine and didnt display any symptoms of failing. Once I added pressure it became glaringly evident it was leaking and causing my idle issue. I ripped the plug out and capped it with a tapered rubber plug with a big bolt to expand it and seal tightly until this weekend/next week when the charger will come off again.
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Joined: Jan 2016
Posts: 599
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2004 E55
