AMGSC

I had to abort this dyno at 4400rpm due to AFR running as high as 14.9 at one point. Got an CEL on the way from LA to SD for the dyno. Could that cause the car to run lean all of a sudden? The CEL keeps popping up usually about a week of driving hard. I reset it and it comes back a few days later. This all started when the Kleemann headers and relocation of the O2 sensors.

This is strange because Vadim just handed my car back to me with documented AFR of 12 a few days ago. I just wanted to get an independent dyno and the results were dramatically different. JBA Performance used a small fan in front and a medium fan over the top and dyno'd it in both 3rd and 4th gears. I am attaching a video clip so hopefully you guys can help me diagnose the problem. I am also attaching my aborted dyno chart and data sheet.

Any feedback would be appreciated....

http://media.putfile.com/AMGSC-C55-DYNO-07-19-08

I was really hoping to keep it running to 6000rpm so that the rwhp could catch up to the 579rwtq but had to shut it down prematurely. Once Vadim fixes the O2 sensor problem and corrects the AFR back to 12 then I should get a complete run and see what only 8psi of boost can do. Thank god I removed the 12psi pulley.

Jakpro1

VERY smart. Better safe than toasted.

Curious as to what the CEL is? Ever pull the code?

Would help to know what the car is saying.

ChicagoX

It almost looks like the O2 wasn't sampling correctly.

splinter

It’s only proper that you address this matter discretely and confidentially with your tuner, IMHO.
Besides, he’s already addressed your ill-advised test here.

Because your car is so heavily modified with myriad aftermarket parts, it’s entirely reasonable that you should expect and anticipate a lengthy running-in period (and subsequent tweaking) to ensure everything is working as it should. It’s all a part of the horsepower game that goes with the territory you’ve chosen to explore.

I’m a persnickety SOB, and yet VRP has worked on mine with outstanding results. They’ve been the only technicians to take a wrench to it, besides me. This post is not intended to pass judgment on them – it’s to merely remind you that Vadim is a highly respected member here and is one of our country’s foremost MB tuners.

I value the vast knowledge he has shared with all of us. Kindly take it offline until you’ve exhausted every avenue toward a successful resolution.

jangy

Sorry for your issues, but can you comment on JBA? they learned AMGs on our cars, but we haven't been back since they moved shops. I called the other day and they do dyno tuning, which is the best IMO. I hate CEL issues and that is the main reason I stayed away from long headers. Hey, at least it looks like your car is warning you when it runs too lean?

jangy

Lets all relax. i know the history and assume the OP didn't mean it as a bash. I doubt Vadim cares if everyone posts whatever issues they have ever had with him or VRP, so no need to bug. This is an easy fix. Not like the initial tune..

rflow306

+1 Bad or dirty dyno sensor, especially when you see very little change in afr readings from the sniffer.

Thericker

Isn't Dynodynamics a dyno where they remove your rear wheels?

BenzoBoi

no...

If I'm not mistaken...Dynapack is the one where they remove your rear wheels...or at least I think that's the one...

ChicagoX

Thericker

Thanks guys

psk145

I wasnt impressed with JBA's dyno when I first went to get my stock dyno. It just seemed like they were running antiquated software. They didnt even strap the car down for mine. I ended up with some really high torque values.

414HP, 492 TQ

So Im not sure how accurate it is. Plus they couldnt plot A/F with the dyno. They had a printout that I guess could've been imported into excel, but I would have thought the program could have done that.

blackbenzz

579wtq on a dyno dynamics dyno??? That dyno is broken!!! lol

AMGSC

I did'nt write them down but will run down to Autozone to scan and record the codes. Cory at Kleemann also asked the same question.

AMGSC

I agree that the AFR sensor at the shop may have been faulty. I should call and ask when was the last time they calibrated it.

SLK55R

no way in hell your car can be pulling 579 rwtq.

cldriver

I'm having a similar issue with my Kleemann Headers+Kleemann cats. Let me know what CEL code you pull out. I got the following:

P2098 Post Catalyst Fuel Trim Bank 2 System Too Lean
P2096 Post Catalyst Fuel Trim Bank 1 System Too Lean

Still working it out with Cory and the shop that installed them.

No use in disconnecting battery or resetting the codes. What that does to CEL is temporary, your car's OBD monitor codes are reset and will start running thru a series of OBD monitor tests. Once it completes a particular test (for me it was the the catalyst monitor), you'll get the CEL codes again.

chiromikey

i'd hate to hear what you guys would say about my run on dynocomp's dd machine!

chiromikey

hey amgsc,

tell me all about your heavily modded monster (it helps me to justify my heavily modded 748r)! pm me if you want.

DFW01E55

Why?
My CL55 pulls 563 without the airbox.

SLK55R

you realize that we are talking about a NA 5.5 motor with a Kleemann supercharger right?

AMGSC

We'll see once I get the AFR corrected and the O2 sensor CEL fixed.

I witnessed the run myself and even recorded the whole thing for you guys to analyze. Can't you see the computer drawing the line as it was being run?

I had another forum member present as well as 2 employees of JBA present. According to the guy who ran the dyno, if the AFR was safe he would not have cut the dyno off and ran it to 6000rpm. He refused another run because he felt the AFR was unsafe. I am running on 2 extra psi here so don't be so shocked at the big numbers. I even attached the dyno chart and data sheet. JBA is no hole in the wall. They are a MAJOR tuner and even have their own line of headers and exhausts. Check the internet. They do custom dyno tuning on the Dyno Dynamics everyday and had 4 other cars dyno'd before mine that day and 3 more waiting in line so I doubt the equipment was faulty. The guy who dyno'd my car (Derek) is an member here so hopefully he will read this and chime in. He owns a modded C43 so he knows how to dyno a benz.

No worries, I am having Vadim redyno it after he fixes everything (if he can't I'll just go to Kleemann to get my tuning done from now on). I also have another appointment to go back next Saturday to JBA for another Dyno Dynamics set of dynos. With AFR at 12, I could likely hit over 600rwtq and who knows what rwhp?

AMGSC

You are right on. Vadim tried the battery disconnect/computer reset since all my Nav addresses are wiped out now and the CEL just keeps coming back.

My buddy cleared it with the ODB II scanner and it comes back in a few hours again! I will list my codes tomorrow after I pick up my new ODB II scanner from Autozone and also give Cory a call.

Thericker

Man your always in controversy.....

AMGSC

Just Truth In Lending, I meant Spending!

I bet that Dog or yours can put out 600lbs of torque too!