nekkro-kvlt

Hi everyone,
Hi imported a 2005 Mustang GT from Florida which has 35K Miles.
The car have an electrical problem, which according the the seller was not present whent he put the car on the boat.

I have the engine light on, and diagnostic showed error code with the oxygen sensors, and some ignition problem.

I changed coils and O2 sensors, but still no improvements (same error code displayed).

the symptoms are that the care have a huge loss of power, especially at low rpm, and when I push down gas pedal, after a while, power come (can be after 10/20s ...).

Sent it to the garage where he tested the ECM, some oil pression sensor, retested O2 sensors... and everything seemd OK, but then there's definitely sth wrong.
He noticed that it appears only cylinder 3/5/7 (and probably 1) are affected, so it seems sometime I run for half the motor which explains the loss of power...

This has to be electrical problem as the guy tried to unconnect the O2 sensor which put the motor in preset configuration as he told me, and with that he doesn't see the behavior where only half the motor is running.

If anyone here experienced the same issue and/or have an idea to fix that, that would be awesome !

Thanks !

Nuke

When you mention electrical problesm, 2 major issues come to mind which are chronic issues with the entire S197 line up to about '09:

There's a TSB for a water leak issue which results in water dripping over the Smart Jumction Box (SJB) located in the passenger side kick-panel. If your car sits outside, dap a tissue on the carpet at the base of the kickpanel and see if it picks up any moisture. The SJB will corrode and cause all kinds of electrical gremlims.

The charging system is a weak link; both the OE battery and alternator can degrade, causing problems with the other and then resulting in electrical issues due to low system voltage. However, your issue doesn't sound related to this since it seems to be affecting only the odd cylinders.

I'd check very closely for the water leak. The only fix there is to repair the leak and replace the SJB (and anything else screwed by the water/dampness).

nekkro-kvlt

Thanks for your answer. That would make sense since on the boat I guess the car got some water, even if it's in a container it's not water proof...

To be more specific, the guy told me that the tension measured at O2 sensor is stable, but it should be vary many time a sec to adjust the fuel consumption in real time. In my case, it seems that for some reasons the ECM doesn't care about O2 sensor voltage and thus keep sending lot a fuel, and as the motor has too many fuel it loss power (and consumes more fuel as well...)

Anyway, I'll have this SJB checked !