I finally got my 91 upper/lower engine wiring harness, and now my car runs! But there are a few things I want to work out, like the fuel pump not working...... I had run a power wire to the intertia switch. Where is the fuel pump relay on a 91? Another problem is its not running great. What should my timing be at? Should I swap out my bosch platnium +4's for some autolites, get new cap and rotor(they look old)? Whats the cheapest CAI? Also, how do I check and adjust tps voltage? What should it be set at? Thanks for any suggestions!
set the timing to 14 degrees advanced with the spout connector out .
For the love of stangs , please throw them plugs in the trash and get some autolites or motorcrafts .
If the cap looks bad replace it .
Tps voltage is checked with the key on engine off between the black and green wires coming out of the tps . set it to .98 vdc . just stick a sewing needle into each wire and check acrost them .
and while your at it clean the mass air sensor . do a search in this forum to find out how , but it will make your car run better .
__________________
Never argue with an idiot. They will bring you down to their level and beat you with experience...
Put your keys up but engine off and get a digital multimeter. Hook the ground wire up where there is metal (i like to use the TP sensor hold screws). Now pierce the green wire coming off your TP sensor on your throttle body. I just got a needle and shoved it through so it doesnt ruin the wire but still gives a reading. It should read around 0.98 V . If it doesnt, turn the TP sensor however it needs to be adjusted that way. You will need to loosen the screws to turn it.
Originally posted by Fordgazm Tps voltage is checked with the key on engine off between the black and green wires coming out of the tps . set it to .98 vdc . just stick a sewing needle into each wire and check acrost them .
__________________
Never argue with an idiot. They will bring you down to their level and beat you with experience...
you should also disconnect the position solenoid on the front of the throttle body when you do this as moving the throttle body with the key on throws off the low idle settings in the computer.
__________________
micheal621.88GT MAF conversion and too many mods to go into.It makes 387 HP at the rear wheels with the clutch slipping at 5200. so 400+ easy
the fuel pump runs when it gets a signal from the dist and as in all 79 up stangs the fuel pump relay is right under your butt when you are driving. Under the drivers seat. If you searh mass-ai- kit on the intrernet you should be able to find a wiring diagram..If not e mail me at aol and I will try to send you the one I found. It makes the wiring much eaiser to sort. when you have the dist wire connected the pump will sound off the instant the key is turned on. I would check to see if you have any loose wires at the dist plug. And if you are setting your timing anyway with the key on and the dist loose you can move it back and forth about an inch when the wires are connected you will here the pumpkick on as the rotor passes its contact. What 5.0 did you go to? remember HO's are a different fifing order than standard 5.0's
__________________
micheal621.88GT MAF conversion and too many mods to go into.It makes 387 HP at the rear wheels with the clutch slipping at 5200. so 400+ easy
the motor is an 89 HO 5.0 out of a mustang. what wires are you talking about, the ones that plug into the tfi module? what if the pump doesn't sound when i turn the distributer?
FINALLY RUNNING!!!......a few tune up questions 
