SerbNerd

Here we go, I have an 01 W210 E430 which has the 5.5 M113 from an W210 E55. I've had the ECU flashed to the W210 E55 stock tune as well.

Threw a wideband on to check AFR pre-cat and the car threw a Check Engine light due to the missing pre-cat O2 sensor. This should throw the car into open loop.

With the car in open loop, my AFR are 15 under idle and I struggle to get anything under 15 under any loading.

All sensors are good, MAF / MAP are both functioning properly. Fuel pressure stays at 60 psi (at rail) always.

I've been thinking of unplugging the Air Pump and maybe mess with EGR as well?

I'm currently stuck and trying to band-aid something so that I'm no running so lean. Even thought of bumping up the voltage of the MAF so that the ECU thinks more air is coming in.

Any suggestions guy? I know the C43 guys usually do the 55 swap but thought I ask here!

Thanks

turbo1k

I don't understand what your trying to do here? You removed the pre-O2 forced the car into open loop and your wondering why it's lean. The car is designed to run in closed loop and use the O2 to stabilize the A/F. Your not suppose to read your A\F before your O2 sensors because it's not a correct reading.

If your interested in finding out your true A/F plug your O2 back in and weld a bung after your post O2 sensor for the A/F to get a correct reading.

Steve

SerbNerd

Thanks for your response

The idea is to see if the car defaults to a "safe tune" as it would when your O2 sensors fail. A car running in open loop doesn't do any fuel trimming to adjust fuel delivery allowing it to increase/decrease fuel based on conditions.

I do agree that I need to weld a bung in and see whats going on with the ECU adjusting fuel. Have you done this and what seemed to be the most convenient pre cat location?

turbo1k

I have one question before I answer.
You said you couldn't get under 15:1 A/F when under a load. How did you apply the load?

Steve

SerbNerd

4th gear pulls and WOT after about 3k for no kickdown

turbo1k

If it were me I would put the O2 back in and put the car on the dyno to make sure everything is good.

As far as you trying to see if it will run safe with a bad O2 I would verify that who ever upload the E55 maps to your car installed the open loop map as well as the closed loop. I don't think you have the correct maps.

During open loop the only factor for the car to try and keep the fuel trims in check are the MAS/MAP and temp sensor.

Who changed the maps and what software did they use? I'm looking for a way to tune my car myself.

Steve

SerbNerd

Yea Dyno seems and another bung seem to be the only thing in continuing forward. Dont want to show up to dyno with bad readings where I have to forfeit runs.

I went to Eurocharged in Chicago. They used their genius tuner (something like that) just to upload tune through OBDII.

I'd like to tune myself as well. Have only been able to find flashes from tuners. Might end up going back to Chicago and have them figure it all out.

turbo1k

They can check your tune without you going there. I would verify you have the correct program installed.

Steve

SerbNerd

I don't have their cable for the remote tuning. They also say its on my end so need to verify with a bung and ECU in closed loop.

turbo1k

Looks like you have a game plan. Keep us updated.

Steve

SerbNerd

Quick update after a long time. I decided to have Kleemann flash my ECU and it turns out that Eurocharged gave me the wrong 5.5 AMG stock map. The map they gave me was for the SLK55 which has a compression ratio of 10.5:1 (along with other differences) while the W210 E55 has a compression ratio of 10:1.

I verified AFR with the wideband and everything is spot on! Learned my lesson and now I know who to visit for Mercedes tuning!

KJI3jflarryfe93

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turbo1k

Thanks for the update. I glad you figured out your problem. I knew something was up with the tune Any chance Eurocharged will give you a refund? Worth a shot.

Steve