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Getting LB7 to pass AZ emissions

Practical Diesel Tuning

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Good evening! I have an 03 LB7 that I can not get to pass AZ emissions. I have a feeling it has a previous tune on it. I have HPTuners and the ECU will not let me read it, but I can scan it. It appears this is a known issue. If I were to buy the SOTF Spade system, will that have better luck working?? The truck runs amazing, but its blowing black thick smoke on the snap test. Ive replaced boost/baro/MAF sensors, changed fuel/oil/air filters. Truck has 271k on it, but runs really good. Any help is appreciated!

It sounds like someone made a large adjustment to your MAF-limited-Fueling table or disabled it all-together. It's a common approach for rookie tuners who don't necessarily understand it's role.

You'll need to get the ECM unlocked and back to stock in order to put another tune on it. You'll likely end up buying a new ECM or paying someone to unlock the thing using brute force. The SPADE cannot flash over a locked LB7. If you'd like help, give us a buzz at the shop 815-568-7920 9-5 cst.



Thank you for your time Nick. So I talked to a guy that has an LB7 ECU for sale. If I were to buy this, can I just swap ECUs and be done or is it going to be pissed that the VINs are not correct??

Glad the info was useful. Just so you know, any ECM you put into the truck will have to be flashed with a file for your specific truck and the VATS will have to be relearned. Without the VATS relearn the truck wont start. With a random file your climate controls (among other things) will be wonky.



Thank you again for your time. I found a company, DHD, that sells reman'd ECUs with the ability to add the VIN and VATS info before shipment. Since I can not get inside my computer at all, I dont have ability to do a read entire and write entire to the new ECU. Im just gonna have to bite this bullet I guess!! Haha!

IF you're using EFILive, they have a 'Brute force unlock' that you can use to unlock an LB7 or LLY ECM. It will wipe out whatever tune is one the truck in the process and must be performed on the bench (using a bench harness). It may take several days. Otherwise, yes you'll need something like what DHD is offering.


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