i have the trouble codes, need some help now!

Hey whats up, i posted a few weeks ago about my 91 Coupe with the problem that when i get over 3500 rpm, it breaks up really bad, seems like it loads up, and starts to smoke and foul the plugs. I had a few guys reply back to me and said to do a self check with a meter on the EEC connector and i could get my trouble codes off of that. Ok so this is the sequnece i used....i disconnected the spout connector at the TFI module, set the timing at 10 degrees initial timing, then i put the spout connector back in, and the timing advanced right to 20 degrees at idle. Under load, the timing advanced to about 32 degrees. so i did the self test, and the codes that came back were #18 (SPOUT circuit open or spark angle word failure, or IDM circuit failure or SPOUT circuit grounded). #19 (Failure in ECA internal voltage)
#49 (SPOUT signal defaulted to 10 degrees before TDC or SPOUT open). I think those are the codes that apply to the mustang, it also read out code 58, 68, and 28, but in my chilton manual they are not checked off for a code refering to the 5.0L mustang. I just wanted to know if someone can help me out who understands what i should do, of if they know what is wrong. THe car still completely breaks up when you hit about 3800 rpms, carrys on for about 10 -15 seconds, then returns to idle normal. Last but not least i checked my fuel system, i have the pump hardwired to a switch, and the these were my results. I put a fuel pressure guage on and it was at 32 psi to start, then to check the regulator, i disconnected the vacuum line and plugged it, my fuel pressure went up to 42 psi. So its not the regulator, or the fuel pump. The only thing i found funny was that when the car is idling and running normal, the fuel pressure sticks at 32 lbs, but when i get it to 3800 rpms and the car breaks up and almost shuts off its so bad, the pressure actually fluctuated from 30 to 40 psi the whole time it was breaking up, then when the idle returned to normal, the pressure was back and steady at about 32 psi....and this is with the vacuum on the regulator. I dont get it....can someone lead me in the right direction, any help is appreciated....thanks everybody!
 
I don't get why the computer would throw codes that don't apply to your car, but then again I am not sure what the VAT is either?
Maybe someone like JRichker can answer that?

If your engine has an erratic vac signal when the problem occurs then it is expected that the fuel pressure would jump around. This doesn't signify that the problem is fuel related.

Guess all I can contribute is a bump.

jason
 
i dunno what mods you have done, but sounds like your fuel pump is not able to hold pressure at higher RPM. have to find out why your pump is flucuating, if it is getting ready to go out or if something else is the problem. have you changed the filter? have enough gas to cover the pump sock and not starve the system? 32#'s with vaccum sounds a little low to me. i think the pressure difference with and without vac. is like maybe 5#'s or so, not 10. bump your pressure up to around 37 or 39#'s with vac off and see what happens. just my few bits of change, so i may be way off.
 
Code 18 - SPOUT out or wiring fault - look for short to ground in SPOUT wiring going back to the computer. Possible bad TFI.


Code 19 - Engine off - No Vehicle Power (pins 37 + 57) or bad PCM VPWR Diagnosis. This is a wiring problem that is from a bad ECC power relay, bad connection, bad fuse link or a bad computer. The ECC relay is located on top of the computer under the passenger side kick panel. Pull the connector off any fuel injector and measure the voltage on the red wire: if its 12 volts or better, the ECC relay is OK. If the ECC relay is OK, pull the kick panel off and measure the voltage at pins 37 & 57. If it is 12 volts or more, then the computer's diagnostic firmware has taken a dump and is defective.

Engine running - Erratic idle during test (reset throttle & retest) - Idle Set Procedures