1st of what’s up TMS
I traded my side by side straight across for my 2007 GT car is in great shape. Long tubes, No cats, I put straight threw mufflers to tone it down a bit. Car also has a short shifter, cold air intake, an thumper cams. After getting it home I’ve done a few other things like services all the fluids, new alternator, cam sensors, all four 02 sensors, drilled/slotted rotors, tie rods, lower control arms an more. Car is amazing an hella fast. Came with a dyno sheet from Cali making almost 350rwhp I’m in East valley AZ so I’m sure it’ll need a tune but I want to get it threw emissions before I do.
About 40miles or 36hrs car keeps popping check engine light due to upstream 02’s showing lean.
car runs great an I’m thinking of picking up a stock ecu tomorrow. As of 4hrs ago I’ve checked timing an it’s good. Chain an phasers are new, I replaced both VCT’s an all 02 sensors at the same time. Pull the injectors an tested em (good) checked fuel pressure (good but changed the pump anyway) 2 cans (1 brake- 1 carb) trying to find vacuum leak. All I can come up with is the ECU/Tune
If anyone can add if as to what I can check or do I’m all ears an would greatly appreciate the assistance

 

Car definitely needs to be tuned for those modifications; it must have been tuned previously for the dyno run, but apparently something changed. I would focus on what you changed since you bought it.

There is almost no way it will pass emissions without cats . . . best bet is to bribe the inspector; but unfortunately computers can't be bribed so I think you are out of luck. (and I am joking, personally I would never do that and would not seriously suggest that anyone else do it either)

Usually the CEL is thrown by the lack of rear O2's, or the rear O2's reporting that the cats are not working . . . which they aren't, because they are gone. There are some posts on here from people who have been able to fool the rear O2's but it's iffy at best.

The lean code comes from the front O2's, and suggests that the car was not tuned for the CAI; but I don't know how it would have gotten decent dyno results if it was not tuned correctly at that time.

PS -- I see you posted your own thread!

 

Sorry for rambling on the 1st post but in short yeah the car was tuned in Cali, once I got the car I changed both up an down stream 02 sensors because it had a light an the upstream tested bad. After I swapped them out the car ran way better when it was cold up to operating temp. What’s funny is I only get a lean code from upstream sensors an no codes from downstream, could be because of the spark plug extenders 👌 but yes with every day I have the car it’s becoming more clear that it needs to be tuned for AZ

 

Not only does your car need tuning for AZ? but also to prevent causing potential serious engine damage due to the lean codes coming from the front 02's

 

Little update. Other day I taped up my air filter a bit. Put miles and heat cycles on the car. Boom passed emissions today an got my tags. Have a few more lite bolt ons planned then it’ll dyno time 👌

 

I didn’t mention that I was gettin a random cam code before but since I got it to pass I figured I chase it down. Pulled the front cover this morning to check everything 1st hand an everything looked good other than the front seal an cover gasket. Was jamming to music but a few times I could have sworn I heard a noise from bank 1, finally I turned down the music an gave a good listen an WTF a bolt backing out the rear of the phaser!!!! Guess I’ll head to the dealer an grab a new set

 

Ok, those are not stock. Well, the phasers are, but those plates on the back are replacements for the original phaser plates, Comp Cams phaser limiters or lockouts, to prevent the computer from moving the cams around too much/at all.

And for what this is worth, there's no way in heck that I'm not putting some orange or at least blue thread locker on those bolts, just because this can happen. That the instructions don't say to do this is deplorable. The Instructions in question, acquired from LMR.com: https://latemodel.cachefly.net/downl...s/CCA-5449.pdf



Did they tell you all the mods that were done? You might want to know all that now, because it seems you are getting gotchas from not having all the info... man. backed out phaser bolt. Just...

/This is why they say 'buyer beware'...

 

Your absolutely right on all counts. I didn’t realize what they was till I put the 1st one on the bench. End result is I pulled them both off an used a little blue on all the limiter bolts then put them back on with new phaser bolts. I’ll put the cover on an finish it in the am.