Off-the-line throttle lag FIXED
I finally solved the off-the-line throttle lag on my '01 C240 M112 V6 and want to share my experience.
I was extremely aggravated (ever have that happen LOL?) to apply the
throttle from a dead stop only to have nothing happen for up to 5 seconds...
then REEEEEEE there she goes! This behavior didn't seem correct to me.
After performing the throttle reset procedure every 2 to 3 weeks for months
(yes, months), one day while I was out to lunch, I had to stop very quickly
to avoid being smashed by a cell phone driving a gigantic bus (some people
call them SUVs)... just to realize I didn't have power brakes like I did a
second ago! I could reproduce it again and again by braking hard twice.
I spent a whole weekend inspecting all the vacuum lines on the engine
and found nothing. After doing this again the next weekend, I realized
I wasn't seeing something... so I decided to inspect them with the engine
warmed up... and lo and behold, the partial crankcase breather hose
(I believe this is the term) was fsck'ing LOOSE at the cylinder head!!!
This is a short 4 or 5 inch rubber vacuum line that connects from the
back of the driver cylinder head to a red 90 degree plastic elbow that
rests within an inch or two of the air mass meter electrical harness.
Strangely enough, it seemed OK when cold, but when warm, it was
practically falling off.
One $0.10 hose clamp later and problem solved - haven't used the throttle
reset procedure in 3 months now and it's just as driveable off-the-line
in W as it is in S mode.
I hope I can help others by sharing this info, and don't get me started
on the rear SAM and power seat controllers LOL!
I was getting 3 - 5 seconds of lag from the time I applied throttle
from a dead stop to the time the engine raced off to redline (with very
light throttle too!).
This is all I can get with my cell phone - you can see the red 90 degree
plastic elbow at the bottom of the picture. I placed a small hose clamp
at the other end - it's visible just to the left of the air mass meter
electrical harness.
If I didn't already know it was throttle-by-wire, I wouldn't guess it
by the way it drives now.
I was getting 3 - 5 seconds of lag from the time I applied throttle
from a dead stop to the time the engine raced off to redline (with very
light throttle too!).
This is all I can get with my cell phone - you can see the red 90 degree
plastic elbow at the bottom of the picture. I placed a small hose clamp
at the other end - it's visible just to the left of the air mass meter
electrical harness.
If I didn't already know it was throttle-by-wire, I wouldn't guess it
by the way it drives now.
Ima go look at mine when I get a chance

M271 == I4 supercharged.. The MAF is in a very different place from the m112 (and maybe the m272).
edit: could someone w/ more technical know-how chime in on what exactly this thing is and what it does?
edit again: DarthBudice - did you have any other issues w/ CELs and what nots?
Last edited by TruTaing; Jan 23, 2008 at 06:33 PM.
Ima go look at mine when I get a chance

M271 == I4 supercharged.. The MAF is in a very different place from the m112 (and maybe the m272).
edit: could someone w/ more technical know-how chime in on what exactly this thing is and what it does?
edit again: DarthBudice - did you have any other issues w/ CELs and what nots?
real-time data (it's not information until you know what to do with it LOL!)
on ST and LT fuel trims, O2 sensors, and such. The part that tipped me
off to it being a vacuum problem was braking two times quickly I lost
the vacuum assist at the second iteration.
Hope this helps.
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but i do hate that 3-5 sec delay it SUCKS.. how did you get the clamp all the way down there... can you take more pix if you can please thank you!
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I know this is an older thread but I'm going to try my luck

I need to change my MAP sensor cause it's not working properly and also I noticed that the rubber lines are cracked here and there. Anybody have parts numbers for the rubber hoses for M112 2.6 V6 ? I can't find no info or maybe I'm just searching in the wrong place



Just today I learned this may cause the problem. The CPS is a commonly known issue for the m112. The only reason why I didn't do it before is because I had a clunky o2 sensor and the MAP (and didn't think of the CPS)
Today I found a vendor close to my place so I'll order it these days and hopefully will be able and have time to change it.
I'm also thinking of changing the fuel filter but if these two don't fix my problem then I really don't know what is wrong...
First I'll do the CPS then we'll see the rest
After the CPS was installed and everything put back to place the car fired up no problem, went for a drive and it seemed like it's running a few extra horses(butt dyno). I left it cool for about 2 hours. When I went down it cranked a few times until it fired up. Stopped it and started it again and this time it was like instant.
Now my question would be what else can cause that delay when starting? What else should I check or do in order to get rid of this hesitant start ?
Also if fuel filter is old might as well replace it as it is cheap and hold the pressure regulator. (make sure to buy OEM/OES as aftermarket ones have been known to have bad regulators.
How many miles are on the car?
The valves you are referring to are for checking pressure on AC lines.






