I have a 2001 Volvo V7 T5 that runs a 0261206828 ECM with Bosch ME7.

Some history on the car is that it had a Stage II IPD Tune with supporting modifications (Turbo Back Exhaust - Air Cleaner). The car was running lean on the IPD tune so I used their MTE Softloader to flash the ECU "Back to Stock".

What I'm fighting with is that the ECU seems to be commanding Lambda 1.0 at all times. I have no PID available on my scanner to confirm this but I have done some backup work - I created an over Rich condition (MAF interception) and at WOT under load and 10PSI boost the STFT would go -22 to -25 and bring me right back to Lambda 1.0.

With the front O2 (WB02) disconnected I'm able to use the MAF interceptor to accurately control fueling and I can adjust fueling under load down to the 12.5 range. Fuel supply is not an issue here.

I'm a competent tuner but I don't know enough about Volvo's code to understand its "logic" in this situation. I have checked what I would guess be conditions for Enrichment - Throttle Signal is good, RPM is good, Coolant Temp is good and Both MAP and MAF are reporting correctly.

Using scan data and a WB02 it "LOOKS" like Volvo is "Commanding"  Lambda 1.0 at all times, no Enrichment happens at all - Please, if someone could help explain some of the other conditions that need to be met in the ECU coding to achieve a WOT Enrichment it may let me see something that I've missed. I do have 1 ECM code - ECM-4010 - an EVAP code - My experience says that a manufacture won't dangerously lean out a tune because of an Emmisions code though (Or any code for that matter).

Thanks in advance!

I have been in contact with IPD and they have given me a PID that shows me commanded Lambda. I have a Datalog that proves the ECU is aiming for Lambda 1.0 (14.7:1 afr) at WOT at 10psi of boost!

I'd love to know why the hell it would do this

I have asked IPD and they're essentially saying its not possible that the data is correct - Even though I've confirmed it with with a secondary wideband. I have no software/hardware capabilities other than the MTE Softloader and the IPD cable.

The log I sent them was using the "stock" tune (returned to stock via MTE so I beleive its not entirely stock as it has their loader etc?). I've asked if their could be corruption with their file but they seem unwilling to send any other files for me to flash.

The log file is attached. It clearly shows Lambda 1.0

It surely shouldn't target Lambda 1.0 at WOT. There should be some PE enrichment under boost. I'd expect to see Lambda 0.8 ish

I've been able to save a screenshot of the log. As you can see the Lambda Commanded is not FIXED at 1.0 as it moves around on over run etc but its solidly commanding and achieving 14.7:1 under boost.

Of all the engines I've ever tuned I've never personally seen a commanded air fuel ratio of 14.7:1 under wide open throttle. Can anyone confirm that it Volvo actually programmed it this way? When I looked for other peoples logs they we're showing AFR's of 11-12:1  as I would expect to see from an OEM setup.

Well, then you have obviously not seen enough. And obviously not read enough for tuning engines, sorry.

Try to find out, why an OEM should run engines at Lambda 1.00 as long as possible.
Small hint: we are talking about year 2000 introduced Euro3 Engine from an OEM who likes it's environment

Of course they do req lower than 1 under certain circumstances. In most of the Volvo bins I've seen from that era, the lamfa map is all 1, and the bts egt limit is at around 950 degC. So one WOT pull wont be enough to make it request something lower than 1. Sustained wot runs are required for that in those cases.

Very interesting information and something that I wouldn't have found else where - I thank you for that. To me, it looks very foreign as usually we're more concerned with ensuring a complete oxygen burn than emissions. I have countless GM, Ford, Dodge etc BINs that are commanding .80-85 quite early on in their load tables - although they have started to act a larger "Delay" into their Power Enrichment now.

I will do some more testing and see what I come up with. I would LOVE to be able to modify the tune and upload but I'm not sure if the IPD cable is compatible other loaders other than the MTE Softloader.