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Engine Help requested in identifying how to resolve engine light issue

  • Thread starter Thread starter Ianslaney
  • Start date Start date Sunday at 2:23 PM
I

Ianslaney

New Member
Dec 9, 2020
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1
Vancouver, Canada
Sunday at 2:23 PM
#1
  • Sunday at 2:23 PM
  • #1
Good day,
Several years ago, a I purchased an 03 Mustang GT that had been sitting for 12 years. The previous owner had not registered it in his name and didn't know much about it. He was selling about 30 cars at auction.
When I finally got to the car, we drained the stale fuel, changed the fluids etc.
After adding fresh premium fuel, the car started immediately, but the engine light came on.
The codes came back as:
P1000, P0172, P0175, P1130, P1150 and P1152, which all come back to the upstream O2 sensors. I changed them and still have the same codes.
The car has a few performance upgrades which include:
A Vortech V2 supercharger with upgraded fuel injectors, BBK intake, K&N cold air system with Thompson intake pipes, Snow Performance water/meth kit, Diablo Mafia, no cats, rear O2 sensors have been simmed. The car is burning quite rich according to the installed gauge.
I went to a local shop, who suggested that I needed to replace the stock mass airflow sensor with one that had a larger throat, to move more air, but before throwing money (perhaps unneccessarily) at the car, I'm wondering whether the issue can be resolved using the Diablo Mafia voltage adjustment, to lean out the fuel?
I looked at purchasing a handheld tuner to resolve my issue, but the upstream O2 sensors seem to be tied in to the engine light. It seems the only option I have, is to reduce the amount of fuel being injected or accessing more air to the system.
I'd appreciate any advice in this regard.
Thanks in advance,

Ian
 

Bullitt347

I have been doing it wrong this whole time
15 Year Member
Mar 23, 2007
4,017
3,012
204
Middle of Maine
Sunday at 2:40 PM
#2
  • Sunday at 2:40 PM
  • #2
Just because you have O2 sensor codes does not mean that the O2 sensors are bad.
The sensors are just reporting, in your case, a lack of switching and reading rich.
Reading rich can be caused by vacuum leak/s or engine miss-fire among other things.
Remember, the O2 sensors do NOT read how much fuel is in the exhaust, they read how much Oxygen is in the exhaust.
Excessive Oxygen can be caused by a over Rich condition, and a Lean condition which can be caused by too much fuel or too little fuel. Incomplete combustion, either by too much or too little fuel can cause a too rich condition. Bad spark plugs, vacuum leaks, bad plug wires, MAF bad or out of calibration, exhaust leaks and such. It could also be cause by bad wires in the engine harness.
Any signs of mice or rodents in the engine bay? Corrosion or frayed wires/harness? Electrical connector integrity, grounds?
Lots of things can be at fault. Heck, even the ECU could have an internal fault.
Edit:
You say the "Installed Gauge" reads rich.
Question, does the engine actually run rich? Black smoke, exhaust smell etc?
 
Last edited: Sunday at 2:47 PM
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