I was having trouble with my Omni 3 bar getting a p0107 code. I could only find a Omni 4 bar locally so installed that and car finally started up but now it won't idle has no power very sluggish throttle air fuel ratio is 17+ while cruising and 14+ under boost. What do I need to change when switch from a omni 3 bar to a 4 bar? Is a new tune required? The car is a Evo 9 running SD.

How do I add my rom file to this post so you can look over it?

Thanks

 

The new sensor has different scaling. You'll need to change the tune.

 

So just the scaling for my map or is it more involved then that? This is my DD and I'm out of town so if there is anything I can change just to get it running so I can drive it home and get another tune.

 

https://www.evolutionm.net/forums/ec...evo-8-9-a.html

 

Rom was already changed for the 4 bar as far as scaling goes when installed. Is there anything else that the 4 bar would throw out on the tune?

 

Not that I know of. Any ECU can use any MAP sensor, it just needs the right values inputted in order for it to properly calculate the sensor's voltage output. If you're really in a pinch, you could adjust the MAP sensor scaling in ECUFlash until your car is driveable. Do a log with Evoscan and Map Tracer to see where you are in your fuel map. Adjust until you are idling somewhere between 30-50 ish load. Do not do any WOT runs until you get a new Omni 3 bar or get your car retuned.

Also, if your Omni 3 bar crapped out, send it in and you'll get a free replacement.

 

Are you sure the map sensor is your problem?

 

Got any other ideas? The only other thing I can think of would be to check wiring/connection to the MAP sensor.

 

Pretty sure it was the map sensor. Had a p0107 code. It would not start and if it did start would immediately die no matter what I did. Swapped
out to the new 4 bar re scaled the rom flashed it back to the ecu car fired right up. It runs but tries to die when you take off until revs get up past 3000 and when coming to a stop. A/f is very lean when driving and it's very sluggish. I have a shop going to tune it next week but thats the soonest they had open. I'm just trying to get it so I can drive it till then. I'm out of town working and its the only car I have to drive.

 

Another question. are you running in closed loop or open loop? If you are in closed loop, check your high/low crossover values. That could be one possibility. Is your problem only during idle and part throttle driving?

Something that popped into my head is that if your 3 bar sensor was not scaled correctly from the get go, it's possible your tuner tuned around it to make your car work. It would be best to get another Omni 3 bar sensor.

 

Open loop as in what? At wot still lean between 14-15 power comes on and it runs smooth just lean and I don't want to get into boost to much. I was thinking along the same lines as the 3 bar was junk from the start which means the tune is junk now that I have a working map sensor.

 

Sorry, I meant are you sure the new map sensor is the problem? If it's scaled correctly, maybe there is another problem?

 

If you don't mind, try posting up your MAP sensor scaling values.

 

0.51 25
0.90 49
1.29 70
1.69 96
2.08 120
2.45 144
2.84 170
3.24 195
3.63 255

 

Those values are correct. Could you post up your ROM file here? I'll dive into it to see if I'm able to spot anything.