what can make your mastang run lean?

 

LOTS of things, bad o2s, bad mass air, mass air wires in sensor being dirty, fuel pump going out, dirty injectors, fuel pressure reg gone bad, not enough fuel pressure. whats your symptoms, how do you know its lean?

 

Did a diagnostic, checked the spark plugs and it was white on the elctrode, getting a fluttering at high rpms

 

There is nothing anyone here can do to help, until we know your combo.
We need to know what modifications you have made.

What codes did you get on the diagnostic test?

When did the problem start?
Had any work been done to the car around that time?



jason

 

A vaccum leak will cause you to run lean. Any backfires or sputtering, especialy when the engine is dead cold?

 

Yeah, i was going to say, if you have one, put a vacum gauge on it and see what it does at high rpm.