Na86

ok so i bought another base s4 for 100$ with a supposed "blown apex seal" did the poor mans compression test, and sure enough, 3 and 3 strong wooshes, so the apex isnt busted. it wasnt getting spark to the coils so i replaced the computer ( or what i think is the computer from under the drivers side) with one from a 86 gxl that i have, and replaced the main relay. this fixed the no spark thing. then i realized that it was just the TRAILING coil that i was getting spark from, so i replaced the coil from this s4 tII that i have, and that made the leading sparked, SOO i have all 4 sparking, and now i realized that there is a LOT of fuel leaking from the back of the car (by the gas tank) and i guess this may be why the car isnt starting now. so i guess the question that i have is :

1: is the GXL supposed to have an extra metal computer looking thing under the steering wheel area that the BASE wont have? i was thinking maybe an AAS computer??

2: what is the black plastic thing in the same area (by the fuse block) it has 3 connectors and it says on it : "CPU FBO1", hazard, flasher..etc... what is this thing

3. where is the actual computer that sends signal to the coils (not the one under the pass. side)

4. what could cause the leaking fuel, it only happens when i crank the motor and its alot of fuel...i was thinking maybe a line off the pump came undone or is messed up, and thats why the car isnt starting is because all the fuel is leaking on the ground...

RotaryEvolution

iTrader: (30)

the ECU main engine computer is located under a metal shield under the passenger compartment carpet where the passengers feet sit.

a fuel leak could be caused by many things but it could be that the fuel pulsation dampener is leaking, it is a common failure point on our cars as well as the fuel lines when they get old will crack and leak.

cwsttu

1. dont know
2. cpu does not control any engine functions... it controls things such as engine sensors and siganals for turns, and other misc electrical stuff includint the idiot guage
3. should be the main ecu that controls spark, goes off of the CAS on front of engine
4. check the hoses that go to the tank, like you said one might have come off... i doubt its the PD because you said its leaking in the back of the car, until you fix that leak you wont know if the pd is leaking because fuel is not flowing through it yet....

good luck

cwsttu

oh yeah and the extra computer under steering column might very well be your P/S computer if the car came with power steering because thats where it is located though i dont know the color of it.. its been to long since i been under there

RotaryEvolution

iTrader: (30)

didn't notice it was at the back of the car, more than likely it is a fuel line rotted out or a ripped/cracked fuel hose.

patman

iTrader: (3)

bad fuel line. The computer that controls the engine is the ECU, and it is located on the passenger side under the carpet. the only other thing that is inside the car that does anything of real importance is the fuel pump relay, which is a little plastic box on the steering column.

pat

Na86

what does that fuel pump relay look like?