Guys I need your help I've been changing part left and right, and I still couldn't find the issue, my x type 03 2.5 , stallions when I step on the gas pedal, sometimes loses power, sometimes goes off. I'm getting crazy, because I don't have any check engine light on. Could you please give some feedback? I'll appreciate it. Ty have a bless day.

P.D I've changed : water pump, high rail pressure sensor, thermostat, custom made the pcv valve hose, gaskets from the oil pan , o-rings from the imt, and spark plugs. Note: ( never been changed before) my sis gave me the car.

 

Have a look at fuel trims - lots of posts about how etc.

 

If the plugs have never been changed I would venture to guess the fuel filter has probably never been changed as well. Maybe replace that as a start.

 

I've changed the fuel filter already but the still there. I also changed the fuel rail pressure sensor, but the problem is still there. I found oil on the spark plugs. Do you think that could be the reason?

 

I’m having the same issue! Except when I read the codes it comes out at bank1 and 2 and sometimes it’s the mass air flow that pops up on the codes. It jerks when I try to rev it past 3,000 rpms. I’ve changed both catys, knock sensor, fuel pump, tuned it up. Changed gasket and O rings and yet it still doesn’t let it rev up to more . It’s a stick shift. Idk what else to do with it and don’t want to let it go.

 

In case you're trying to rev past 3000 when parked it's cutting the power to stop you causing damage via overheating etc.

 

sorry, I meant when driving, it won’t pass 3,000 rpms

 

Brikels, post the exact code numbers you are getting. Might want to clear all the codes and then see what pops up so you know what is current.

As was said, if you are getting the flashing light that means you are doing damage to the engine. Probably the first place to look is the coil or fouled plugs. The codes should at least point you to the cylinder(s) that are misfiring.

 

May well be one or more failing coils.

 

Oil on the spark plugs is never a good thing and can cause misfires. I would suggest getting your cam covers sealed up properly, plugs and coil packs properly cleaned up and see if this helps. You should run code reader on the cat and see what DTCs come up and what the fuel trims on both banks read. If you post the trims here, I am pretty sure there others who will help with the diagnostics.