Hello this is my first post (I just joined). I recently purchased an 83 2+2 non-t off of a friend of mine. It's got the engine and tranny of an 81. Alas the issue at hand is the fuel pump. It's not getting power, I've replaced the relay under the glove box, with 2 different relays (they cant all be bad). I don't really know where else to look for issues.... I know the green wire is the positive for the FP when I test it with meter its ground for some reason... (tested off battery both terminals, green wire + battery pos gives 12v.... green and neg = 0v)

When this car went out my friend decided the fuel system needed cleaned out and threw a bottle of seafoam (the whole thing) into the gas tank... he drove it about 20 miles to work after work he drove home and it ran like hell (1500 rpm full throttle without enough power to move the car even the slightest) Everyone said its the injectors.... so the car sat for some time (i dont remember how long about a year give or take)....

Well yesterday we were tinkering with the car, I hot wired the FP with jumper cables and 2 leads to get inside the clipy thing in the hatch... well the FP works we were pushing fuel through the lines.... connected everything back up and the car still wouldn't fire (fp hard wired). The gas could be bad, but that aside its self why wouldnt the fuel pump work?

Also what would be the best way to install a anti theft device on the car.... I was thinking toggle switch tied into FP... maybe even a hard wired FP.... but now I'm rambling.... any thoughts/advice?

 

Could the FP not be getting enough power from the car to push the seafoam-fuel? Maybe there is a short between the relay and the pump.

Also, I am no expert, but wouldn't that much seafoam clog the injectors?

 

if you have the polarity wrong the pump will run backwards and not pump. unless there was no gas in the tank the seafoam is not the problem. plugged suction will do it. FPR shot you aren't getting enough fuel pressure on the rail to inject into the cylinder. you need to get a fuel pressure gage on the ring. run a hose from pump discharge to a bucket and see if any fuel is being moved by the pump.

 

Seafoam is just a solvent - it won't make the fuel to thick to pump

 

The pump isnt getting power.... Ive debated a short in the wire...right now the whole dash is ripped apart, the ecu is exposed i tore it apart and gave it a quick look i didnt see any breaks or burns on it... when i hard wire the FP it will push, meaning it works, its just not getting power.... I changed the relay 3 times, and while I had it hard wired it was moving fuel.... my biggest concern is why isn't power getting to FP... could it be a bad ECU? and if it were how would i test it or get it tested?

 

Does it use a fuel pump control module up near the ECU?

 

No ecu is left kick panel fp relay behind glovebox.... Only thing I've seen so far

 

Only for a turbo models!

 

Week fuel pump!!how many PSI do you have after the fuel filter??

 

I havent got that far yet.... only time fp will run is when hard wired and its a little much going on by myself... Ill get a pressure test kit this weekend and check it...

 

I realize this is an old post, but maybe someone can help. I replaced the fuel pump, the relay (five pin) under the hood. (The six pin relay that is next to the five pin is also identified as a fuel pump relay but I'm having trouble locating a new one.) and the relay under the dash....behind the glove box. Still no fuel from the pump.
What about the fuel cut off switch/relay? Where is it located?
The weather has been too cold and snowy to do much outside the last 60 days and I can't get the car in my garage.

The car sat for about 7+ years.

I looked at the troubleshooting info on the "free manual" I got from this forum, but I'm still learning the locations of everything.

Thanks for any help you might be.

 

^^^ Have you verified that the ecu is getting power? Checked the fusible links?

 

Thank you for the idea, I did "look" at the fuseable links and no sign of burned material as I've seen in other situations. Hopefully it will warm up soon. What is the best way to check for power at the ecu?

 

Interesting posts. If it's any help, the only not-workin' fuel pump I ever had in my Z31s (the '86na) turned out to be a 'bad' ECU (ECCS). When the pump quit, we ran a direct power feed to it so I could drive the Z while we located the real prob. (Pump a big pain to replace - and they don't quit often) Replaced the ECU after much screwing around elsewhere - finally - and the orig pump worked fine off the second ECU.

Easy to check power to your ECU. Check out the Elec Diags in your factory service manual (freebie DL at XenonS130 - S130 Reference ) for the ECU power feed circuits, then key on and check for power at the ECU with your multimeter. Also, car probably won't start with a dead ECU - or run the self-diagnostic either...

Harder to tell if the ECU is a little bad or all good. But check it out anyway. Recycled ECUs are available. Match the part numbers if your current ECU is original.

 

Thank you NismoPick and zxguy, I've been researching as much as possible between everything else going on. I presume you are referencing the "box" on the drivers side interior side panel??? What I did notice was the horn doesn't work, the wipers work only on the wash position, the device that runs a check (lights, wiper fluid, etc) did run through the check cycle, can't get the fan blower to come on, but then again there is no fan switch. The head and tail lights did come on.
I've got to get my grandson now but will let y'all know what I find out this week. I might try to hot wire the fuel pump with 12 volts just to see if it kicks on???? I'll probably end up burning the car up.

 

For the hell of it, before you hot wire it, turn the ignition key on, remove the boot from the AFM and move the flap to the middle or anywhere that is not resting, see if the pump fires up.

 

Thanks Skully, I will try that, what is the AFM? I did look for AFM but didn't see anything that would indicate it. I have "tinkered" with every motorized item I've ever had and all these acronyms are starting to run together.....Thanks again

 

Air Flow Meter, I havent had a zx one apart in a while, sorry I thought the zx had the fuel pump shut off in the AFM as well, I guess it does not. Carry on sir.

 

Thanks Skully, I hope it warms up and dries out soon. I've had this car for over 6 weeks and only had two days (still under 30 degrees) warm enough to work on it. I really appreciate the ideas.

 

I could jump up and down and might try break dancing if I were 40 years younger. I got my car to start and run for 1 to 3 seconds. Hopefully it just had some stale gas past the fuel filter. After trying to start this thing a few times, it backfired.....don't think it's timing because the backfire originated in the front engine compartment, not the exhaust......maybe I'm remembering what causes a backfire from the exhaust backwards????

Anyone know why the volt meter stays on with the key off and out of the ignition?

P.S. The fuel pump came on only after I tapped on the ecu (unit on lower left drivers side kick panel)