Don’t pass 3k rpm

[AeroCoupe]

Car is in open loop when it is cold. This means the ECU is running the engine off of predetermined tables and ignoring the inputs like the O2’s, ECT, ACT, MAP, and O2’s.

When it goes to closed loop is when it starts using all those inputs to trim the fuel to attempt to run at a stoichiometric ratio of 14.7:1.

I am not sure when it goes into closed loop as I have read it’s based on the O2’s heating up and is anywhere from 30-120 seconds or it’s when the ECT registers 140 degrees or so. Someone will chime in with more knowledge than me on that.

Reason I am bringing this up is if the car is running fine in open loop then goes into closed loop and starts to run bad it could be that one or some of the sensors providing input are bad. This should show up in a code.

 

[Mustang5L5]

I'm leaning fuel or ignition here.

I'd hook up a fuel pressure guage and see if oyu can get one long enough to run the line up and tuck it under the wiper. Do a hard pull and see if that pressure holds at 39psi, or if it drops off.

ANd like i mentioned, everything you said here is similar to what I experienced on my car, and it ended up being the coil. I chased everything else and then one day decided to just grab a coil and swap it. Problem solved. Mine was an aftermarket accell unit

 

[Jonatan Issa]

I'm leaning fuel or ignition here.

I'd hook up a fuel pressure guage and see if oyu can get one long enough to run the line up and tuck it under the wiper. Do a hard pull and see if that pressure holds at 39psi, or if it drops off.

ANd like i mentioned, everything you said here is similar to what I experienced on my car, and it ended up being the coil. I chased everything else and then one day decided to just grab a coil and swap it. Problem solved. Mine was an aftermarket accell unit

Tomorrow I'm going to take a fuel gauge to see that everything is fine, yesterday it turned off as if it didn't have gas, I turned it off and turned it on and everything stayed normal but it feel don’t have power, thanks for all guys