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Discussion Starter #1
Lately my car has been starting cold with a slight idle hunt that is not noticeable on the tach. Another symptom is the car is shutting off whenever I am slowing down or coming to a complete stop. From searching it looks like its the ICV, is this part cleanable with brake cleaner? I do not think it is a loose battery connection as that would not explain the idle hunt. Maf's were done 40k ago with CPS done probably 30k ago. I think the jailbreak tune turns off my MAFS regardless.
 

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Wohoo I was hoping you would reply! You've helped out so much in the past. If it is not elbow a good cleaning will get me on my way? or is a replacement needed. I know in my Acura no matter how much you cleaned it, no difference.
 

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If the ICV is sticky you usually get a code. Clean it though. The stall when off the gas is 90% of the time a air leak below the throttle plates which 90% of the places are in the ICV system.Take off the plenum and get a can of carb or throttlebody cleaner and spray around at idle. You will find it at the same time spray it though the ICV to clean it.
 

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Discussion Starter #6
Car will run without tubes and plenum? So Take that all off, leave car idling, spray cleaner over, if the idle drops/car stalls then that's were the leak is correct?
 

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You have it. Do a search I have explained with many more words several times in the past. Electrically unplug the MAFs.
 

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Discussion Starter #8
Hey Sailor, I took off the plenum over the weekend. Ran it without Mafs connected and sprayed TB cleaner in that general area yesterday. I sprayed the plastic elbow pretty good and noticed no drop in Idle. I then went around all the areas related to the ICV, and nothing caused the idle to drop. I ended up spaying into the ICV multiple times to try and clear it up while running. Did it about 3-4 times and caused the car to stall out once when I sprayed alot in. At this point everything is still apart, but I am not sure what to look for now.
 

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Discussion Starter #9
If it is a hairline crack like that other guy had, Wouldn't it suck in SOME cleaner? I can replace with brass but would like to know true cause of issue instead of throwing parts at it. There isn't much room in that little V.
 

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Discussion Starter #11
Only have ODB reader, Did not pull codes, its not throwing any lights but I know it can be. Will hook up and read tonight. I honestly noticed no difference. I had a bit of an idle hunt once in a while so it was not consistent.
 

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Discussion Starter #12
Would it be beneficial to remove and inspect ICV and check for noise/ease of movement of flap.
 

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Discussion Starter #13
I just checked my old emails it looks like my tune has alpha N as well, so no MAFS normally anyways.
 

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Would it be beneficial to remove and inspect ICV and check for noise/ease of movement of flap.
You could remove the intake hose to the IACV and VERY GENTLY rotate the valve a little to check the valve for free movement. It is opened closed by separate motors and seems to also have a very weak spring so it bounces around easily. I have done this but I think TIS says don't do it, so at your own risk!

You should also be able to get a helper to press down the gas pedal so you can watch the valve for smooth stroking. Especially check for it returning consistently to the same position when the gas pedal is released.
 

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Discussion Starter #15
I'll try that when I get back. I did replace the evap valve late last year. I don't see how a leak would manifest itself overtime from that install so I doubt its from that. Would bad CPS cause this?
 

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I just checked my old emails it looks like my tune has alpha N as well, so no MAFS normally anyways.
It could still be MAF's. Jailbreak recommends use of the MAF's, so if they are connected, they are working. When you get it back together, try running without MAF's.
 

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Discussion Starter #17
So If im following correctly, If it runs better without MAF's, that will tell me it is indeed the MAFS? I had these things go bad about 40k miles ago, and it would do funny things like causing the car to misfire, stutter, run alot of gas, But i've never had it shutoff almost consistently going into neutral.
 

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I didn't read the responses, but you can clean the ICV, remove it, spray carb cleaner, and it should freely spin. If it doesn't freely spin then it's clogged.

-R
 

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So If im following correctly, If it runs better without MAF's, that will tell me it is indeed the MAFS? I had these things go bad about 40k miles ago, and it would do funny things like causing the car to misfire, stutter, run alot of gas, But i've never had it shutoff almost consistently going into neutral.
When the car is coasting down, while the rpm is >~1000 rpm, the DME shuts off fuel completely (an emissions thing). Then as it approaches idle rpm, it starts injecting again. I'm suggesting any glitches in the MAF signals at low air flow may upset this process. Unlikely maybe, but it's such an easy check to do.
 

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What a timely thread. Mine has stalled several times now only when the engines hot and usually soon after a restart (on a warm engine). Never on a cold engine. It would start fine, and as I pull out, usually after I clutch in from 2nd gear, like at the end of the street, the engine would stall as the rpms drop with clutch in. It would restart just fine, but obviously a dangerous situation. Now that I think about it, the idle rpms weren't really smooth either. After reading the threads, I sprayed the ICV. What a difference. The idle rpms are now a very steady and smooth 700, and rpms when I clutch in will drop to 700-800 and hold steady. Before, the rpms would drop down to 500 before bouncing back up to 800 or so (if it didn't stall outright). I'm sure I saved $$$ by catching this thread rather than bringing it in.:cheers:
 
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