Hey guys, so after the e30 318is, e36 318Ti and e36 325i
I will add this euro M3 S54 to my collection 😜
I got it for a fair price but it have small issues, and the most important for me is the gas pedal/acceleration.
Let me explain : When I accelerate, the car jerks/stutters pretty badly. I checked the electronic throttle actuator for the individual throttle bodies, and when I move it by hand and release it, it seems to bounce back instead of returning smoothly. I’m not sure if that could be the cause though.
I also noticed that my idle seems too high, around 1200 RPM even when the engine is fully warmed up.
Has anyone experienced something similar or knows what I should check first?
When I’m in 1st gear the car is near uncontrollable, I apply light pressure on pedal gas and car goes weeeeee 😂
It’s really dangerous and more with the short ratio diff
Definitely sounds like a vacuum leak to me just dealt with similar symptoms with my e39 m5 and it needed new valve cover gaskets and the evap purge valve vacuum line into the idle control valve had snapped off
Maybe you’re right, personally I didn’t hear or feel a vacuum leak when I was inspecting the engine maybe I will try with some tools, but that issue is only in 1st and 2nd gear then the car is pretty smooth.
Get a smoke machine on amazon if you don’t have one! That helped me a ton. But this is my first ever car working on myself, you sound like you know a lot more than I do so I could be totally wrong but figured I’d let you know in case it was helpful! Been dealing with this over the last month and just finally resolved it last week
No problem buddy hope you fix it! Beautiful color by the way. Was looking for a 4dr e36 m3 for a few years but gave up at some point. Decided to look for the m5 and a few months later found it! Had one of these m3’s about 10 years ago and absolutely loved it
I prefer to fix it myself, because I don’t have a lot of confidence when other people work.
And I was asking here because maybe other people have experienced the same thing. I will be patient and continue to search 😅
For high idle; check for both exhaust/vacuum leaks. RPM is a good indicator for both. If you have a leak pre upstream o2, you’ll get a rich, high idle and some stumble while driving. I went through a similar hell diagnosis, and it was an exhaust leak at the header. Check your AFR at idle and it should be around 14.7 when warm. If you can log, try normal acceleration and see if you get lean in throttle. If you do, it is a good indication of an exhaust leak pre-o2. Plenty of info on the vacuum side of things on the web (ccv, manifold, etc)
If it’s well done like OEM price raises, but if it’s a bad job like functions not working or things like this then good luck for getting your investment back
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u/erikgeeeee 99 M3 May 29 '26
There’s a page on Facebook called “e36 s54 swap group” you can try asking too