82 Brat need fuel help..

[HGJ]

ok so we got a 82 brat, and long story short its been sitting for 5 years. all fluids are changed both filters also..heres my question..The fuel pump is good, I pulled and tested it. now with the ignition on it gets no power,with the engine cranking it gets 10 volts. I know there is a fuse somewher,but can not find it,my sourec says its under the dash on the fuses box side..all that out and hanging still no luck..help please.

thanks

is it safe to run a switched 12v to it?

[HGJ]

anyone...:-\

[edrach]

anyone...:-\

Not much to go on here but I'll try to give it a go. I'd be surprised if it's a fuse issue. I don't know of a fuse that will allow power (even if only 10V) to the fuel pump when the ignition is off and no voltage when the igition is on. However, it would indicate a poor connection somewhere between the power source for the fuel pump (fuse block or ignition switch). When no current is flowing (fuel pump off) there could be some residual voltage there; as soon as you put a "load" on it by switching on the ignition, that 10V is dropped across the bad contact somewhere along the line and can't get to the fuel pump.

 

Maybe someone has a service manual and can send the wiring diagram showing where the fuel pump gets its power and what connectors are along the way which could use checking/cleaning contacts, etc.

[maozebong]

the service manuals can be downloaded from a couple places. try googling "ea81 service manual"

[SuBrat84]

Sounds like maybe a bad relay or something.. like it's getting forced voltage when you are cranking the engine.. but then none otherwise. throttle position sensor? I would probably wire the pump to one of the 12v systems that comes on with the car (like the radio or something...)

Good Luck!

[GeneralDisorder]

It has a fuel pump control unit and sounds as if it's working just fine. There will be no power to the fuel pump except when there is a tach pulse (cranking or running).

 

Sounds like there's no real problem with it to me. If you can't get it running I would look elsewhere for your problem.

 

GD

[HGJ]

Not much to go on here but I'll try to give it a go. I'd be surprised if it's a fuse issue. I don't know of a fuse that will allow power (even if only 10V) to the fuel pump when the ignition is off and no voltage when the igition is on. However, it would indicate a poor connection somewhere between the power source for the fuel pump (fuse block or ignition switch). When no current is flowing (fuel pump off) there could be some residual voltage there; as soon as you put a "load" on it by switching on the ignition, that 10V is dropped across the bad contact somewhere along the line and can't get to the fuel pump.

 

Maybe someone has a service manual and can send the wiring diagram showing where the fuel pump gets its power and what connectors are along the way which could use checking/cleaning contacts, etc.

 

thanks for the reply, i was thinking the same thing till i found out that there is a cranking type sensor. i will check and clen all contacts..thanks

 

the service manuals can be downloaded from a couple places. try googling "ea81 service manual"

 

thanks i will try that

 

Sounds like maybe a bad relay or something.. like it's getting forced voltage when you are cranking the engine.. but then none otherwise. throttle position sensor? I would probably wire the pump to one of the 12v systems that comes on with the car (like the radio or something...)

Good Luck!

 

that was my first thought but is that safe,,,we did it all the time on VW,s

but what hapens when your key is on and car is not running?

 

It has a fuel pump control unit and sounds as if it's working just fine. There will be no power to the fuel pump except when there is a tach pulse (cranking or running).

 

Sounds like there's no real problem with it to me. If you can't get it running I would look elsewhere for your problem.

yes it does have a fuel pump controler that does that,,but i have no fuel out of the pump.

or better yet pump does not run when cranked,but runs with direct 12v..

 

Thanks all of you for your time and input!!

any other thoughts..in this manual http://www.worldwidecm.com/HTKYSA.pdf

there is a refranc to a fuse that controls either the controler or the pump it self.

I am stumped..

is it safe to hook that pump up to a switched 12V?

[Yo'J]

Have you pulled the fuel hose at the firewall in the engine bay at the fuel filter to see if it squirts while cranking yet? That will tell you it works.

 

If it does, its the carb or disty or coil or plug wires. If you wired the pump in yourself, is its possible that the wires are reversed?

[maozebong]

hook up a timing light and see if you are getting spark while cranking. if you are you could have very bad gas still in fuel lines somewhere, possibly water. see if you can get it running by spraying starting fluid in the intake.

[TomRhere]

A workaround for a faulty FPCU on these vehicles is this oil pressure switch, http://www.rockauto.com/catalog/moreinfo.php?pk=2399944

 

It's for a '76 Olds Starfire. They had electric fuelpumps, power was controlled by that switch. No oil pressure = no fuelpump. An adapter will be needed to install it on the oilpump.

 

Much safer than direct wiring of the pump.....

 

edit;

NAPA lists these numbers for the switch. ECH OP6610 & ECH OP6627 They also list the connector ECH EC428

Edited August 1, 2010 by TomRhere
added info

[HGJ]

Have you pulled the fuel hose at the firewall in the engine bay at the fuel filter to see if it squirts while cranking yet? That will tell you it works.

 

it does work' date=' bench tested..no fuel out..

 

If it does, its the carb or disty or coil or plug wires. If you wired the pump in yourself, is its possible that the wires are reversed?[/quote']

 

no it doesnt pump..and still factory wired for now.

 

hook up a timing light and see if you are getting spark while cranking. if you are you could have very bad gas still in fuel lines somewhere, possibly water. see if you can get it running by spraying starting fluid in the intake.

 

got spark,,second thing i checked.

and yes started with starting fluid,then died.

 

A workaround for a faulty FPCU on these vehicles is this oil pressure switch, http://www.rockauto.com/catalog/moreinfo.php?pk=2399944

cool thanks

It's for a '76 Olds Starfire. They had electric fuelpumps, power was controlled by that switch. No oil pressure = no fuelpump. An adapter will be needed to install it on the oilpump.

 

 

Much safer than direct wiring of the pump.....

thanks a bunch, I will try this one..

 

edit;

NAPA lists these numbers for the switch. ECH OP6610 & ECH OP6627 They also list the connector ECH EC428

 

thanks for the good info...much apreciated..

is the adapter someting i can buy,or do i have to make it?

Edited August 2, 2010 by HGJ

[HGJ]

thanks for all the help..still stuck.

any one have a good pdf of "ea81 service manual"..thanks again guys

[2manetoys]

thanks for all the help..still stuck.

any one have a good pdf of "ea81 service manual"..thanks again guys

 

Try this one and Copy & save all 15 chapters.

 

1982 ea81 FSM

[HGJ]

^^^ thanks ^^^

[HGJ]

i keep getting a error msg..and they wont download.

[HGJ]

can anyone tell me for sure where the fpcu is on a 82 brat????also where is the relay for the fuel pump??

and is that a part that is still availble?

Edited August 4, 2010 by HGJ
need more info..

[naru]

can anyone tell me for sure where the fpcu is on a 82 brat????also where is the relay for the fuel pump??

and is that a part that is still availble?

 

Under the dash,extreme LH side,I think.

Relay is built into the FPCU.

 

Fuel pump should run on 10V.

Might want to check pump ground.

[HGJ]

good idea..I will check the ground..thanks

[ruparts]

good idea..I will check the ground..thanks

 

hi, i'm not sure about the 82 cars but the 85-89 cars have a engine computer under the steering column. the fuel pump on those is normal to run only when the motor is turning, and will not run with just the ign switch on. when you first turn on the ign switch it will run the pump for a second or two, then go off. the pump ground circuit goes to the engine computer for a ground, i have found sometimes that it is gone bad and the problem you are having is the result. run a separate wire to ground the pump and see if it will run then, again the engine has to turn to cause the pump to run except that first 2 seconds after you turn on the ign switch. with a new ground it should show voltage to the pump cranking the engine, if it does then its working and should look for other issues.

[HGJ]

sounds good..I will do..thanks

[TomRhere]

Carbed vehicles don't run the pump "key on-engine off" or "during crank". Only when engine is actually running.

[HGJ]

Carbed vehicles don't run the pump "key on-engine off" or "during crank". Only when engine is actually running.

 

You know I have read that a bunch...and it didnt register till just now..duh..

so in theroy no run no pump..it started for a few seconds with starting fliud, depending on how long that wsa it should have started then..I guess im gonna jump it for now to elimnate some other possabiltys...

DAM FPCU

[HGJ]

is there any way to safley pull power for the pump from the altanator?

that would make more sence? if its spinning we get 12v if not no 12v..make sence?? I am pretty profeciant with wire..lol and relays and want to do it rite but most of the ways ive seen to get around this saftly seem way to complicated..or at least more complicated than need be..maby im wrong..i dont know.

[brat82]

Howdy,

When I got this brat, it hadn't been run in 2 yrs. I could get it started but not keep running. I finally decided to look into the carb, as I couldn't really change the tuning/running. The carb was all varnished up with old gas compound. Had to buy a rebuilt carb and have been running ever since(10yrs?). The carb I have is a stock carter/weber, and I like it.

[HGJ]

after all this..i am not able to get gas fraom tank to pump..is the tank easy to pull? it doesnt seem to have a whole lot of sopace inbetween tank and rear dif..