bajaman

It's been a long time since I posted. I gave my car to my son about 3 years ago as I felt it was time for him to have it; he'd "grown up" in that car following his mom and my divorce. Believe me, there have been MANY times I wish I'd kept it, as well it's an FD after all, lol! Over twenty years of owning it...anyway, my son called me and said, "The car just shut off and died on the freeway, I made it to an exit ramp and it won't start...". He had it towed back to his apartment complex. I suspect the fuel pump, given the little information I have so far. It cranks just fine, but doesn't won't fire up. I am off work this week and if the weather cooperates I plan on traveling to where he lives and working on the car. MANY years ago I picked up a fuel pump from a Supra as the mods I'd done to the engine were better supported with the Supra pump, but I never installed it...still have it. I put power to it and it spun, then shut off...wouldn't spin again. Fooled with it a while and it spun again, then died again. I am not sure if these pumps are looking for pressure to stay running...?...but I don't know if I want to risk installing it. Thoughts? OEM RX-7 pumps are hard to find...my local dealer doesn't stock one but says one is "available"...for about $500. I know I am REALLY jumping to conclusions here without having even seen the car, lol...but I want to try to be as prepared as possible when I go to work on it.
Again, thoughts...opinions...suggestions?

Thanks!

FDAUTO

iTrader: (4)

Aem 50-1000 is what you want as a replacement pump

If you suspect the pump to have failed then your first test will be to check if the pump is working at all. The easiest test is to put the key to 2 and see if you can hear it prime. If you're unsure, you can squeeze the fuel line on top of the hanger to see if its hard.

If that doesn't pan out then youre going to check for power to the pump when the key is moved to the start position (starter turning). If you have power but no pump operation then pull the hanger and inspect the bulkhead connector for failure. They melt sometimes and you get failed pump symptoms. This is typical with aftermarket pumps though.

If that checks out then remove the pump, apply power and ground to it directly and verify it doesn’t operate. If it doesn't then easy day, replace it and easy day. If it DOES then the real adventure begins of chasing wires. The fuel pump circuit is relatively easy so walking you though that would be pretty simple.

Jeff76

I really don't have anything to add specifically about your old car. However I was told when I bought my fuel pump for my FC, DO NOT RUN THE PUMP DRY!!! It can possibly overheat?? Yes, it was a stern warning.

DaveW

That's a warning that can apply to almost any fuel-injected (gasoline) vehicle.

And on that note - is it possible that the fuel gauge has misfunctioned and he's actually out of gas? I had that happen with my carbureted Datsun 240Z back in the '70's.

TeamRX8

iTrader: (2)

it will/can run dry, but without fuel passing through to help keep it cool, will overheat and fail.

I have the gas gauge issue on the REW RX8 I bought. The way the PO set up the fuel system, the fuel siphon isn’t pulling fuel out of the RH saddle into the LH saddle where the in-tank pump is to feed the external surge tank where the dual main pumps are located. So it will run put of fuel with the gauge still reading 3/8 - 1/2 full. Fortunately I was just outside the garage the first time it happened, learning about it the hard way.

The next surprise was starting the car one day and letting it warm up while sitting inside several minutes in the garage, then getting out to see E45 fuel flooding the floor at the garage entrance (car had been driven straight in and parked). Fortunately I got the car shut down and several gallons of fuel cleaned up without it having caught fire. Which likely would have trapped me in the garage before burning the place down (rental storage type garage, only one way in-out). Turns out the entire fuel system had been run with non-ethanol SS braided rubber hose originally, but later on was switched to running ethanol fuel.

Dealing with purchased project cars is fun …
.

bajaman

Thanks, guys. Yeah, I mean I just BRIEFLY connected it to power, like for one second, just to see if it would run. Back in the day, those Supra pumps were all the rage for swapping out a stock FD pump. But looking at the box I got it in '05, and of course it was used then...but supposedly in perfect condition. One would assume a dc pump stored in a box can't "go bad"...
I figure when I get up there the first thing I'll do is jumper the ground and FP terminals on the diagnostics port, turn it on and see if I can hear the pump run in the tank before doing anything else. Or jumper the ground and ten pin and see if there's a fuel pump relay code displayed.
There have been times in the past, and again now, when I do wish the FD had OBDII capability, lol!
And yeah...I assume it has fuel and the gauge is working. When I had the car it was pristine, kept in perfect condition, regular maintenance, garage kept, etc. TLC was its middle name. I can't say the same for the last three years of its life...but that is what it is.

DaveW

TeamRX8...

Whew !!! Sometimes we're just lucky.

DaveW

One of my favorite sayings is: Don't assume anything. Assumptions too often come back to bite you in the butt.

ecurbd02

iTrader: (7)

If you need a fuel pump let me know! I upgraded mine and have no use for my old one. I believe it’s an R32 pump. If you need it PM me and I’ll cut you a deal on it

Pete_89T2

iTrader: (4)

I'm agreeing with DaveW on the "never assume" advice. But once you're able to check out the car in person, and have ruled out that the tank simply hasn't been run dry, it will be a matter of troubleshooting the trilogy of combustion - fuel, spark & compression. If you hear the fuel pump priming with the key on, that's a good sign that the fuel pump is at least working and the engine is most likely getting fuel - yes an assumption, but since the car was previously tooling down the freeway, it's a reasonable one. Also a reasonable assumption that compression is OK, or at least good enough since the car was running fine before and it didn't sound like your son was running it flat out when it died. If your son tried multiple times to start it and failed after the tow, it's likely flooded, and will need the usual de-flooding procedures prior to trying to start it again. Pull the plugs to inspect for flooding and let it dry out, test for spark and go from there.

Sgtblue

iTrader: (16)

Hope you get it sorted out in short order. Regardless, good to see your name pop back up on the board.

gracer7-rx7

iTrader: (16)

Was thinking the same thing

sunkat

iTrader: (2)

Ha ha, did he even check the gas gauge That happened to me when I was 19. Car died and I spent 20 minutes with the hood up trying to figure it out. Some old guy stopped to help, leaned in through the window, turned the key and told me what my problem was.