90Stang306

Ok so I have a 1990 mustang GT. Its got some motor work done to it. Its a 306. Has heads, headers, cam, exhaust with no cats, chrome molley push rods, Cobra computer, 24lb injectors, cobra MAF...Minor mods basically. At idle the car runs fine. If I rev the engine sitting still it revs up fine. As soon as I give it gas to go it breaks up. i'm at a loss right now as to what I should do to fix it. Here is a list of things that have been changed and checked. any input would be greatly apreciated. Timing chain, temp sensor ( because I had a temp sensor code), 2 o2 sensors, mass air flow sensor, idle air control valve, throttle body gasket, intake manifold gasket, EGR valve, plugs, wires, cap, rotor, ignition control module and distributor. The timing is currently set to 10 degees because I wanted to keep it simple rather than advancing or retarding it. Fuel pressure at idle, revving in neutral and under load are all good. No current codes stored in the computer. the car was running great and the next day it ran like ****. Had it towed to my shop and it went from barely starting and moving and backfiring to being able to start and run although the idle surges for about a minute and then evens out. I now have some power back. I can spin the tires coming out of first and spin them shifting in second but im still getting popping and some engine break up. The car is still not back to what it was and im pretty much out of ideas right now as to what may be causing this problem. Any kind of input would be greatly appreciated because I'm lost right now.

90Stang306

Just an update. I disconnected the battery to let the memory be wiped out. Then adjusted the fuel pressure down to 39 without the vacuum line on. Reconnected the line and took her for a ride and BAM almost 100% better. Still one more step to go before shes back to normal again!