I was told by a dealer I need a new ecu. My car has a bunch of problems. Im getting 5 mpg less than what i usually get, theres a slight delay turning over my car, i have a CEL light code p0171 for car running lean, and anytime I go over 5lbs of boost my fuel cuts out.

I have a 2012 gsr that only has 3,000 miles on it. They are stating my ecu has been reflashed and cant be put back to stock so ill be needing a new one. Can a bad or poorly tuned ecu cause all these problems?

 

Yes.

I would first check the physical setup. Make sure the fuel pump relay is good, make sure the fuel pressure regulator hose is zip-tied and not loose. Maybe even do a boost leak test.

Then have someone in the aftermarket look at the ECU tune that's on it.

Fuel cut comes from high load or artificially low limits set somewhere like a Valet mode. If the MAF or MAP sensor is bad you may see errorneous high load values that trigger fuel cut.

You can have someone help you flash back to stock for your ROM ID which is something I'd try before letting them replace the ECU. Especially if you're paying.....

Good luck.

 

I have had boost leak tested, maf sensor swapped, spark plugs replaced, fuel relay checked, fuel pressure regulator is on securely. So now im lead to believe its the ecu. I was told to get it reflashed but that may or may not fix the issue is what ive been told. So to save me the most amount of money i was recommended by the dealer to simply swap out the ecu. Thank you for the reply, I just needed some clarity to my issue.

 

Yea check out the tune now... it's probably been tuned and brought back to stock incorrectly.

 

Having the same issues with my 2004 RA 2.4