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82_super_supra
06-03-2006, 04:13 PM
82 supra. Fuel pump works, injectors are getting a signal, EFI fuse is fine, the relays are fine, still no power to the pump. Anyone have this issue before? Could there be a connector loose somewhere? The cars at my shop now, and we're in the midst of trying to figure out whats going on. I ran fine, until i went to start it one day, all of a sudden the pump is getting no power. I tried hard wiring it with a toggle switch, and the pump came on, but the engine still wouldnt fire. Any ideas? thanks.

darren

BillyM
06-03-2006, 08:09 PM
If the timing's spot-on (check with a timing light) and the fuel pressure's there (check with a fuel pressure gauge), assure its getting good vacume and you should have a running car.

You try the fuel-pump check-connector?

--BillyM

Angkistrodon
06-03-2006, 10:40 PM
You have no power to the pump at the wires/plug?
I had a little issue with a bad FP, when I jumped the pump it ran fine(I thought) but when I swapped it with a new one,BIG diff.

Kevin Kisseberth
06-03-2006, 10:46 PM
I have the same problem GL. I am about to give up

SILVPTYPE85
06-04-2006, 12:06 AM
Had a similar issue with a 83 Celica GT 22RE. By the symptoms you described sounds like it might be the MAIN RELAY. I know you said you checked the RELAYS, but I was working on a 83 CELICA GT same exact symptom as you described. It took days to get the car to act up. This car was driven by a litte old lady, only had 60k on it. After hours of running the car at idle, it finally lost power to the fuel pump. There are two relays on this particular one (NOT SURE IF YOUR SUPRA IS WIRED THE SAME) there is one on the passenger side front and one in the fuse box under the hood. Turned out being the relay in the fuse box under the hood... I think it was labeled MAIN ??? I remember partially It was about a year ago that i worked on it. I might take a peek at a wiring diagram when i get a chance.

How did you check your RELAYS??? a relay that clicks doesnt mean its working correctly.....
Not questioning your intellegence, just wondering how you tested them.
The problem with relays are that they can fail intermittently.

This if from TSRM, coulnt find any diagrams for your 82........



http://www.cygnusx1.net/supra/library/TSRM_MKII/fi/FI_044.html

82_super_supra
06-04-2006, 12:19 AM
i am an idiot. turns out the pump was getting power, but there was a washer over the banjo fitting to the fuel line that was blocking fuel flow. Weird tho, when i checked for power with the key on it didnt have anything at the connector to the fuel pump, maybe it only gets power during cranking...? anyways im happy shes running again...now to throw in my 5spd and turbo

SILVPTYPE85
06-04-2006, 12:37 AM
Cool glad to hear you got it running!!!!!
sometimes something basic and simple will get over looked:ugh:

BillyM
06-04-2006, 10:23 AM
Weird tho, when i checked for power with the key on it didnt have anything at the connector to the fuel pump, maybe it only gets power during cranking...? anyways im happy shes running again...now to throw in my 5spd and turbo

...the fuel pump does not turn on just because the key is on. If you push your AFM open by-hand, within the first 1/4" of travel you hear a metalic click, that's the fuel pump switch. ...there is also a connector next to the AFM that isn't connected to anything, jumper the two sides together and it does the same thing.

...ohyea, and the reason it is like that is so the fuel pump wont run when the key is on but the engine is not running/turning over (ie, if you got into a wreck, pumping fuel all over the ground)

--BillyM

little_boxx
06-04-2006, 01:16 PM
uh yea my supra did that same exact thing so i chopped sum wires n ran new ones to a toggle switch it works great as an anti theft thing too cuz if you put the switch in an inconspicous place ur set they d be sitting there crankin it over till the battery died ....... i know i'd rather have a dead battery than a missing car........ i'd kill :) hope ya figure it outman late