dropped the tank installed new pump with new sock and new pulsator, filter, relay, fuse, put it all back in with 5 gallons of gas and..............nothing. Anyone got any ideas?
So when you turn the key, you don't hear the pump? Did you pull the old one b/c it also did not work? Maybe the old one worked and what ever caused it to "stop" running has not been fixed, hence the new one is also not working? Have you tried putting 12v power and ground to the one you pulled out? If you do and it works then you know it was not the pump. Then you need to see if your getting power to the relay. If you turn the key, do you hear the relay click? if so, then its not the relay. After that, maybe someone else can weigh in.
the old one was literally falling apart, instead of a pulsator they had used a piece of hose that apparently wasn't gas rated, the guy i bought it from told me the fuel pump had gone out, turns out it had turned the rubber hose to gum and it had gotten everywhere. had to clean out the entire tank of gum and rust, what fun. now when i turn the key you do hear the relay click but the pump does not make any sound at all.
Check out this post n how to jump the fuel pump to get it to run https://www.fiero.nl/forum/Forum2/HTML/141986.html . There are more posts on how to do this. This will eliminate the fuel pump relay / ecm etc so if it works then one of those are the issue. If it does not, it would be the wiring directly to the pump or the pump itself.
FYI, when I got my Fiero the fuel pump was wired into the ignition coil to bypass the relay. After removing the by pass the fuel pump would not turn on. I replaced the relay and still no fuel pump. After running through the diagnostic steps in the service manual, I traced it back to a bad ECM. I replaced the ECM and that fixed the issue. However, if you can hear your relay click this is probably not the issue.
i went out and straight wired the pump to the battery to check it, it does nothing at all so i guess its the pump and will replace the brand new pump tomorrow
I would first check the connector. If that doesn't do it replace the pump. Sounds like you got a Chinese made pump of questionable quality. .
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
i have checked the fuse box got 12v there, but when i check the wire right at the firewall first in the engine bay and then in the interior and im at 8.5v. i cant figure out where I'm losing voltage or why. i straight wired the fuel pump to make sure it worked, not permanently. so is there a connection or another relay or something between the fuse panel and the firewall?
the fuel pump works if it has 12v going to it, but i dont have 12v going to it i only have 8.5v. i have 12 coming out of the fuse panel but by the time it gets to the firewall its down to 8.5
replaced the pump as of now i have a new pump (i know works because i straight wired it to the battery since it didnt prime with the key) a new relay i assume works because i hear it click when i turn the key i replaced the computer because i was told by several sources that could be the problem there is 12 volts coming out of the fuse panel but only 8.5 at the firewall since there is only 8.5v the pump wont work i cant find any other relays or fuses between so i am at a loss as to where my voltage is dropping can anyone think of what im missing?
so could i run a new wire from the fuse panel thru the firewall and connect it to the harness in the engine compartment that the fuel pump connects to? the only connections i have found are the harness that connects to the fuel pump, from there to the firewall, the one going thru the firewall, and where it goes into the fuse panel. if that is all there is then running a new wire without the extra connections seems like it would do the trick, am i being completely ignorant or will that work?
???? what do you mean? it reads 12v at the fuse but only 8.5 at the back firewall, would it not fix it if i ran a new wire? I must not understand what you meant.
Where are you reading 8.5 volts? It should be at the connector next to the ECU...not at the relay. You can do what you suggest and it will probably work, but if you want to keep the wiring stock, test for 12 v. on the connector pin.
on the inside of the car right next to the ecu before the connector going thru the firewall i put a tiny slice in the jacket of the wire just big enough to get the tip of the tester in, it reads 8.5v
Okay....if you test the same wire at the fuse box using that same method and get 12 volts, you found your problem. I would splice in a new wire at those 2 points. It seems the connector is not a factor.
OK, I've talked to a couple of dealerships and got them to talk to me a about a car they cant pull up on their tablet, that took some work. What I've come up with after talking to them is that I should run a new wire from the fuse panel to the firewall and splice in the fuel pump power as well as the sending unit power into the new wire I run and that should fix the problem. Does anyone see any potential problem with that fix?
OK, I've talked to a couple of dealerships and got them to talk to me a about a car they cant pull up on their tablet, that took some work. What I've come up with after talking to them is that I should run a new wire from the fuse panel to the firewall and splice in the fuel pump power as well as the sending unit power into the new wire I run and that should fix the problem. Does anyone see any potential problem with that fix?
while i appreciate that you have sent that a few times, i dont think it goes to my car, it does not represent the same color wires that are in my car
This is very basic information that needs to be resolved before anything gets fixed. What colors are you seeing? The diagram has proven to be correct for 40 years.
Multiple threads on the same issue will confuse everyone, especially you.
[This message has been edited by Gall757 (edited 04-09-2020).]
coming off of the fuel pump there is a black, tan with white stripe, and a pink. the black is ground the pink i have traced up to the instrument panel and at both ends of the pink im reading 8.5v the tan is not even reading 1v nowhere on the diagram can i find a pink wire to the fuel pump
at this point i have stripped off the tape for the main wiring harness behind the dash trying to trace the wires from the fuse panel to the pump
the orange wire from the fuse panel goes to a connector next to the ecu and changes to an orange with black stripe and goes to the fuel pump relay, up to the relay i have 12v so far so good
im going to try to trace the tan wire off the fuel pump now to see where that goes
im going to try to trace the tan wire off the fuel pump now to see where that goes
The diagram above shows you where the tan/white wire goes. One of the places is the ALDL connector in the armrest. Is that in good shape? The other places are the oil pressure switch and the relay. You could disconnect the oil pressure switch to test if it is bad.
[This message has been edited by Gall757 (edited 04-09-2020).]
well im getting .002v on the tan wire at the fuel pump plug with the pump unplugged from it. ive traced it from there to the same connector as the orange next to the ecu to the relay(so they both go to the relay) and the armrest plug, as for the oil pressure sensor i can try disconnecting it but i dont know how that would effect anything unless it was running, but hey ill give it a shot
Wires rarely (never) go bad unless damaged. For test purposes, you can run a wire to see if it solves the problem. But look at connectors for your problems. Look at corroded terminals. Look to see if the terminal has gotten pulled and the wire is barely connecting.
the question is run a wire from where to where? from my fuse i have 12v all the way to the relay with the orange power lead, but after the relay(i took the plug apart and cleaned the crap out of it) which is a new relay im only getting .02v with the tan lead that goes to the fump plug
im glad you said that because i just put the tester on the relay and turned the key on and got 13 volts for a few seconds then went to less than 1v both on the relay and the tan wire at the fuel pump, i thought i had entered the twighlight zone
im glad you said that because i just put the tester on the relay and turned the key on and got 13 volts for a few seconds then went to less than 1v both on the relay and the tan wire at the fuel pump, i thought i had entered the twighlight zone
Replace the relay
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
the new relay that i put in it the other day turned out to be bad, just replaced the relay with a new one from a different store and i finally have gas to the filter, bad news the injector appears to be bad any way to test the injector?
