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318i m43b19 high idle problem

3877 Views 1 Reply 2 Participants Last post by  Daylay7
Hi there!

That's my first topic here so straight to it :)

I own an e46 318i 1999 with the m43b19 engine. So what's the problem with the car:

1. Barely starts when the engine is cold without me interfering with some throttle. This is how it looks like when I touch nothing but the ignition key:

2. While the engine's warming up, the RPM slowly increases until it reaches about 1250 when the engine has reached its normal working temperature. That's two images, first is with A/C off, the other is with A/C on (-200 on the rpm)

3. When I push the gas pedal even the slightest, or (as seen below) I push directly the throttle valve even very little, the rpm goes all the way to about 2500. That makes driving in lower gears extremely unpleasant. Imagine I want to slowly move in 1st or second gear, that's not possible, car does not stop accelerating until the engine is happy with its 2500 rpms.


How long have I had this problem: When I bought the car I did not have any troubles with the idle. However, the computer was acting crazy and it was randomly cutting off the fuel causing the engine to stop. A bunch of stuff was replaced in a shop with not the brightest most competent guys working there until the car completely died and did not want to start, this is when the computer was changed and the car went going again. I was in a different country at that time but according to my father who was dealing with this lovely baby the idling problems started after the car died and the DME was replaced. But it doesn't make sense for the computer to be causing those problems because it's programming logic, it does not brake down in time, it either works on not.

Additional info: Car has LPG, but the problem is there when running on petrol as well with no difference.

What have I Done so far: Replaced the idle control valve with another one from a used car. No change. Sprayed with starting spray all around any links of the inlet manifold in order to find a leak but no luck there. Took off the upper section of the inlet manifold to check if something was wrong there but everything appears to be ok, replaced the seal rings above the flange (no7):

Again, with no luck.

Any ideas fellas?_a__a2_
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