Engine Missing or running rough

I have a 92 mustang with a 5.0 that's running really rough and not much power. I'm confused as what to try next on it. It has a B cam, 24# injectors, eldebrock upper n lower intake, but bottom end is stock. I've owned the car for close to 20 years and it sits alot. I have put new plugs. Wires, distributor cap, rotor button, new coil, n new iac. I done a base idle reset, and I checked fuel pressure and it's at 35 psi. I bought a code reader and it gave an egr code but when I try to do the test with it running it almost instantly dies. I tried idling it up, but it still dies when I try to do the test. Sorry for the long text, but I'm hoping someone has ran into this before and can point me in the right direction
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Aug 5, 2020
Tampa Bay, FL
Is this something that started happening on its own or after something was done to the car?

Does it sound like there is a consistent miss while running as if one of the cylinders isn't making power?

I would start by pulling the plugs to see what they look like. Check for any vacuum leaks as well.
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Thank you for your reply. No I haven't done anything to the car as far as mods or anything. It does sit alot and just started running weird one day. I pulled the plugs and they seemed wet n black in color. I'm building a smoke machine n will check for vacuum leaks soon
I did not pull the spout when doing the bas idle reset, I thought that was for setting the timing only. I did unplug the iac. Turned off accessories ran 2 minutes turned off for 2 minutes then turned on accessories n ran it for 2 minutes.

codes showed an egr code while not running the engine, but trying to pull codes while the engine is running shuts the motor off almost immediatly

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
polk county florida
Start by resetting the computer, pull off the negative cable for 20-30 minutes, attach the cable and drive it around for a while then check for codes.