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Torque
12-31-2007, 05:51 PM
When I stab the gas pedal when idling (or push down quickly), the car kinda bogs down then springs back into life ... very inconvinient if you wanna get going quickly from a light and you're not actually staging for a drag-like launch (when I push down gently it revs up smoothly.

Is this simply a bi-product of the heavy dual mass flywheel or am I actually having some sort of issue I'm not seeing? It's not really a big deal, but I would like to make it go away.

Paul in NZ
12-31-2007, 06:34 PM
my 535 is the same,is better on the second stab.....i would go mega squirt or similar if i knew that would make it go away for ever... I asume the big butter fly valave is the main culprit

Torque
12-31-2007, 06:49 PM
my 535 is the same,is better on the second stab.....i would go mega squirt or similar if i knew that would make it go away for ever... I asume the big butter fly valave is the main culpritYes sir, the second stab is better here as well.

The other 535i I had was the same way, but that had 250+ thousand miles, so I can't really compare much with that one since I don't really know how much of it was still functional. ... My m20 525i was same way too ...

As far as maintenance, I am all caught up, short of new injectors and o2 sensor (but it does it when cold too so that rules the o2 sensor out) ... will probably do both come spring time anyway.

I wonder if a chip would make it a little better?

Paul in NZ
12-31-2007, 08:05 PM
i maintain my car pretty well,i thinks its just how it is.....yes chip or something.I know a uy here who has eliminated his afm buterfly valve altogether must ask him how his car copes..i have learnt not to "stab it" feed it a bit of throttle THEN floor it

Torque
12-31-2007, 08:12 PM
i maintain my car pretty well,i thinks its just how it is.....yes chip or something.I know a uy here who has eliminated his afm buterfly valve altogether must ask him how his car copes..i have learnt not to "stab it" feed it a bit of throttle THEN floor itMe too ... sometimes I forget though; I can only imagine what a tool I look to some onlooker when I bog down taking off. :D

edit: I guess I'm happy it's not just my car and I wont spend the rest of time chasing the issue (that doesn't exist).

myles
12-31-2007, 10:31 PM
My 535i doesn't do it, but my 525i does. I'm just about certain that the fuel pressure regualtor is faulty. I've just got a little more testing to do and hopefully it will fix the problem.

Podmore
01-01-2008, 10:50 PM
Try cleaning your ICV. A little brake or carburettor cleaner, blow out the residue with compressed air, then a squirt of WD40 to lube the valve. I had the same problem a while ago, but exactly what fixed it (I've replaced the CPS, TPS and cleaned the ICV) I'm not sure. I suspect the ICV sticking open giving a lean mixture when you crack the throttle. Worth a try and a cheap fix!