4.6L Gt has no power
Hello! Trying to pin point what is going on with my 2003 Ford Mustang GT sohc, automatic.
Unsure if I’m able to post a video of what it does here. Sometimes when I start it, it’ll start fine, I put it in drive with my foot still on the brake and the rpm will shoot up to 1000rpm and drop to 400rpm and then level out at about 800rpm moments afterwards. Sometimes it works fine but sometimes if I put my foot down it’ll accelerate to 40km and that’s all it got with no power at all, if I gradually press the pedal down I’ll get to about 80km but the car is suffering. But it don’t happen all the time (and when I bring it to a garage it’s when everything seems fine)
After reading different posts I have changed the all the ignition coils, spark plugs, egr valve. Cleaned the MAF sensor, idle control valve and throttle body. Check the vacuum system for a leak. Replaced the fuel filter.
Managed to get a computer hooked up to it and took it for a ride to monitor fuel pressure and at idle it’ll be around 40psi +, when I step on it, the pressure will drop and if I hold the pedal down with the car suffering it’ll get as low as 9-10PSI.
I’m not getting a engine light so I have nothing to go by