November 13, 201015 yr Trying to find out why my fp isnt working and I'm having difficulty locating the fp relay on my 85 Brat (no power to fp with key all the way on, no ecu). Is it under the dash, or under the passenger seat?
November 13, 201015 yr Should be just above the hood latch...I've got two types, same shape, different color(blue, black) different pins- one is missing one or its scooted over one notch. I don't remember. My 87 brat's is light blue, 82 wagon is black.
November 13, 201015 yr No actual fuel pump relay, there's a Fuel Pump Control Unit, FPCU. Mounted on the kickpanel, above the hood release. Should be Black with a 6 place connector. Works off disty signals saying that the engine is running, also feeds the choke power feed. I'm not 100% convinced that it actually powers the fuel pump during cranking of the starter. Mainly 'cause the floatbowl should have sufficient gas in it to start the engine, therefore not really needing the pump to run, unlike a FI system. GD has commented on many posts concerning this. So a search of FPCU and GD should get you some good info.
November 13, 201015 yr You should test for power ot the pump when cranking. The FPCU (relay) won't send power though to the pump unless there is an ignition pulse (tach pulse) The unit itself is attached to the drivers side kick panel, just above the hood release. 6 pin connector, has 3 diamond logo on it. ONe of the wires(solid blue?) should get power with key "on" The yellow wire should give a tach pulse. The Blue/red wire is the Fuel pump wire and should get power whenever the Tach wire get's a pulse Black is a ground.
November 13, 201015 yr Think all 3 of use summitted our replies at the same time, (even if the time stamp says otherwise). Had a major slow-down going when I hit the send button.
November 13, 201015 yr Author Thanks guys, I did a search and found the info on the fpcu right after my post. I hot wired the pump to make sure it works, it does. I started the car and it ran for a min, then died. The carb (Weber) is getting fuel, I can see it squirting into the intake. I might have to go back to my original assumption, that I have bad gas. Who knows where the pickup is in the tank? Front or back? Heres my symptoms, they are quite strange... Runs ok, until you stop or turn right. Then it dies I already took the top off the carb to see if theres junk in it, its clean. And I installed a new filter up front (no filter in the back).
November 14, 201015 yr Heres my symptoms, they are quite strange... Runs ok, until you stop or turn right. Then it dies . Probably flooding. Float too high? Tank pick-up problem wouldn`t show up for a moment or two. Bad gas would be bad on left turns too.
November 14, 201015 yr Author Thats why I said its weird. The problem showed up all of a sudden, out of the blue. It acts like its running out of gas, not flooding. Hmmm, just had a thought. Wonder if my choke is closing?
November 14, 201015 yr Might be distributor related - is the tach signal clean? Put a test light on the negative side of the coil. You might not be getting a clean tach signal to the FPCU and that might be part of the running problem and the fuel delivery - being electronic it could happen for no good reason and at any time. I've seen similar bad behavior from the carbed EA distributor modules. GD
November 2, 20196 yr That’s correct DO, and those little black boxes die from time to time. I’ve been lucky with these so far my self. Nice thread dig too do you have a similar issue to this? Cheers Bennie
April 6, 20205 yr Been sitting couple months, wanted to prime carb by powering up the pump at unplugged module connector, couldn't figger how. With keyswitch on there's already power to the Blue/red wire. Anybody got any ideas?
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