need help, slight car running issue

[mineralgrey01gt]

I have a couple of questions about what is the problem with my car. First off I found out that 4 of the injectors were severly clogged. I changed the injectors and the car ran a lot better. Next I changed the plugs and found one was closed shut from putting it in (my fault) and changed all the plugs and gapped them correctly and it ran even better. Now I have to figure out why when I give it gas it falls on its face. There is no codes being thrown at all. All the coils tested good when switching them around the engine. If I ease into the throttle it will take fuel decent then pull a lot better when easing into the boost. If I go WOT it does not want to take fuel. The car sat up and I honestly forgot to change the fuel filter after I cleaned the tank. Could that be the problem? If its a PCM problem wouldnt it throw a code of some sort? Please any help would greatly help!

 

[oldmodman]

Plugged injectors are a sure sign that you may have had crud in the fuel. Leading me to suggest replacing the fuel filter. If that solves the problem then I would also be suspicious of crap in the tank too.

That shit had to come from somewhere. If it is really bad it can clog up the plastic mesh screen on the bottom of the fuel pumps. If the fuel filter does get you an improvement than you should drop the tank, replace the fuel pump socks and wash out the tank.

If the cars runs just as bad with a new fuel filter then you should look to a fuel pump going bad. But not bad enough to trigger a trouble code yet.

 

[03cobra#694]

What car?

 

[mineralgrey01gt]

Tank has already been cleaned out, the oem fuel pump is no longer in use. It has a full Glenn's Performance fuel system with twin 300 lph walbro pumps and an aeromotive fuel filter. Car has a steady 40psi where it should be for fuel pressure. It sat for a while and stupid me flushed all the lines and cleaned the tank really well but forgot to change the fuel filter. Ill try that and if I need to ill drop the tank again and clean it all up.

The car is a mustang gt.

 

[kevinatfms]

What year mustang GT? If its the later 05+ cars then it could be a multitude of issues.


EDIT: you state you read fuel pressure at 40psi? So then tape your fuel pressure gauge to the windshield and go for a test drive. If the pressure drops when accelerating then you know the issue.
It should increase slightly if its working properly. Check the WSM for the correct part throttle pressure reading and you will find your answer as to if the fuel system is the problem.

 

[DHG1078]

In addition to the above post, I would suggest to clean your MAF and check your TPS.

 

[mineralgrey01gt]

Its a 2004 mustang GT. Sorry it took so long to respond got caught up at work. Ill have to get a remote mount fuel pressure gauge as mine is under the hood. I forgot to clean the MAF on it before it went on. Car sat up for 5 years so im thinking about even cleaning all the connections on the CCRM and PCM as well. I cleaned all the connections under the hood before putting it back together.



Also ill add the fuel system is a return style system. Not sure if I added it or mentioned it in previous post