DavesMeanE's

You need to get your car fixed - PM me if you want help

Thanks

Dave

JQuala

i messaged you

Schulminator

OP, was there a final solution?

JQuala

Ya. Found out I had several vaccum leaks. Changed new filters to intake gasket. Was really dissapointed when I found my gaskets just fine. However as we tried putting back the Intake manifold we noticed one of the vaccum lines was being crushed underneath the manifold. We replaced it and as we were putting the airbox back together we also noticed bank 1 of the Y intake tube wasn't seated properly and the metal brace was out of line. After all those fixes the car just feels better, more powerful, breathes normally. However, where I go to dyno has been real busy recently so I can't bring actual data to ease any more of my doubts. When I do I'll repost here!

Celicasaur

Could you please let me know what your vacuum reading is at idle?

Like, let the car idle for a minute on its own and let it settle to whatever it wants to settle to and then please let me know:
Vacuum
Maf
Load

I'm curious

JQuala

Off the top of my head -9 psi and my map is 12-13 inhg. I'll give you an exact number tmrw it's 2 am here in socal

Celicasaur

Oh wow really? If that's correct, then your vac leak woes are not over

I'm guessing the -9 is your ignition timing.

Does your car have a heavy, loud chuggy idle when you stand behind the car?

Ask me how I know.

JQuala

Gulp I changed the o2s, relocated cats, changed all the hoes! All the HOES....etc you know the rest bahaha

-9psi to -10psi is my vaccum/boost according to dashcommand. 12-13 inhg for at idle is my map. I'll give post a video of it idling later when I get all the accurate numbers but it sounds healthy? Like what a lth with an H pipe idling I always thought I was literally hearing the scavenging pulses of the exhaust after I cleaned up the plumbing

Btw, knock knock
"Whose there?"
How do you know?

Celicasaur

I think you might have the units the wrong way around btw....intake manifold pressure is in psi and the vacuum is in in/Hg but either way, if the vacuum is around 10 or 13, it's still far from great man. Also, yeah I'm not sure if the W204 is much louder, but a happy-running engine even with LTHs will sound very reasonable at idle when warm. If it sounds thumpy and loud, it's because the timing is overly retarded to compensate for the engine wanting to naturally raise the idle due to the extra incoming air.



My 2017 has been one giant vacuum leak and these big TBs have been doing it to my life. For the moment I've reverted to oem ported TBs while I decide if I can be bothered to install the bigger ones again.

FWIW a good M156 will be around 22-24 in/Hg at idle when warm with MAF flow of 8-10g/s. Don't take it as the gospel, but that's approx what it should be at.

JQuala

Says -10 boost, 13-15 inhg for map @37% load

Celicasaur

That's really strange...but i guess it is what it is...

What's your 02 sensor voltages? That load also seems high to me... if you're also seeing negative ignition timing at idle, you still have a leak bro

JQuala

I think it might be dashcommand that's off. My timing never goes to negative on idle for on gas. It does on deceleration. My app displays vaccum as vaccum/boost and that's a negative integer shown in psi. While my manifold absolute pressure is in inhg weird huh?

Celicasaur

Ahhh ok, fair play....hehe i can only go off what you tell me, which is what it tells you.

It's all good....keep us posted on your progress man. As a community, we don't share enough actual data to help others down the road, so I'm glad that you're doing this.

JQuala

Good news! New dyno results!