Sleepless in Seattle

Hi. I have an 88 NA and ive narrowed down my problem to my fuel pump not making enough fuel pressure. The Haynes manual say to hook a gauge up to the feed line and turn the car to on position. When i do that nothing shows, but when i crank the engine (Does not start) it goes to 40 - 44 psi.

Im looking for an alternative thats affordable and walbro seems a good choice for $100. but they offer only 255lph. Is that stock in an rx7? or will that be too much for a stock NA?

RotaryRocket88

iTrader: (7)

The fuel pump doesn't run with the key in the 'ON' position unless you jump the test connector. It is a yellow 2-wire plug near the airbox/passenger shock tower. It will also run if you prop the door open on the AFM. 40-44 psi is roughly normal with 0 manifold pressure. At idle, the fuel pressure spec is about 28-32 psi.

A walbro will overrun your stock FPR and drive fuel pressure way up. It's common to see modified TIIs using them because the extra fuel that will be pushed through the injectors can serve as detonation protection. It's crude, but it can work. On an NA, you'll just be killing mileage and power for no reason. There's no need for a fuel pump upgrade on an NA; an OEM replacement would be just fine.

lm38330

iTrader: (1)

have you tried running a t2 fuel pump? i would look into that.i dont think you have to mod other stuff like the fpr and such.just some food for thought

Sleepless in Seattle

ok well we were jumping th ewrong connector then..but while cranking it read 40-44psi. So that was correct?

will jumping the right two pin this time possibly start the car without having to assist with spray? also why does the haynes manual and fsm say fuel pressure is to read 60 to 80??

satch

iTrader: (1)

What ever happened with the alternator light staying on with the key to off?

Sleepless in Seattle

no idea lol. But it went away yesterday when i went to crank the car.

I didnt pull that wire yet to see if it changed. but i will if it comes back.
what does that wire do anyways?

satch

iTrader: (1)

That particular plug has two wires. The B/W wire supplies voltage to the alternator and the W/B is connected to the alternator warning light relay located in the CPU and is responsible for turning on and turning off the warning lights when the key is put to start and then when the car actually is started.

Sleepless in Seattle

oh i see. ok.

i really hope jumping the right wires this time starts the car...

RotaryRocket88

iTrader: (7)

Use the FSM for fuel pressure specs. The only way to get a pressure of 60-80 psi is to "dead-head" the fuel delivery line by sticking a gauge on the end of it. The engine would have no fuel being fed to it, since the gauge would be blocking it off. If you tee a gauge into the line, you will be able to measure fuel pressure while the engine runs.

Sleepless in Seattle

ok so i put the wires in the yellow two pin relay and cranked the engine for 10 seconds and stopped. I then heard gurgling in my gas tank and could hear the fuel pump whirrling. but still no start.
where should i go from here?

im trying to try everyhting before having to replace the pump...im poor.

if spark plugs are wet means im flooded right? well only the top plugs were.

how to you deflood the rx7?

RotaryRocket88

iTrader: (7)

Wet plugs would mean there is no combustion. There is either no spark, or it's flooded. Remove the green 40A EGI fuse, crank the engine for a few seconds, replace the fuse, then try to start the engine with the throttle open.

satch

iTrader: (1)

Have you verified that the leading coil is creating spark?

Sleepless in Seattle

I just removed the egi and cranked. put back and cranked and still nothing. Only my top plugs are wet. bottom are dry.

how do i test for spark on the leading coil?

satch

iTrader: (1)

At the leading coil remove one of the boots and place it back very close to the hole/bore you pulled it from. If necessary roll back the rubber boot. Then have someone try to start the car as you look closely at the small gap between the plug wire and the coil. You should see a spark.

Sleepless in Seattle

oh well yeah i deff have spark... man this is confusing.

satch

iTrader: (1)

Have you tried using starter fluid that is sprayed into the intake cowl?

Sleepless in Seattle

ok. so just to make sure everythings right.

on the ignitors, the ones mark with white are for the front rotor, yes?

the gurgling in the gas tank and wirrling was my fuel pump meaning my pump is still good, yes?

Sleepless in Seattle

yea. thats how we got it to start yesterday. but it would not idle.

So we thought it was not getting its own fuel since if we stopped spraying, it'd die.

satch

iTrader: (1)

You really only want to spray for a few seconds for each start and not try to keep the car running on it. Also, sometimes it's best to disconnect the fuel pump electrical connector plug, effectively turning it off so you could clear the engine of fuel as you go through the spray for a few seconds then start and try again the same thing for a few times then reconnect the fuel pump connector and try to start up the car normally and do not step on the gas pedal at all.

Sleepless in Seattle

oh..we used the whole can....not in a continuos stream though.

so right now. i can hear my fuel pump, im getting spark. when i crank it doesnt start, but will start with starter fluid. it will not hold idle though. when we spray i dont touch the gas at all, just clutch and crank.

i must be getting fuel though because my trailing plugs are always wet.

where should i go form here?

efb17a

Here is a link to the Service manual
http://www.teamfc3s.org/main/factory...ual/1986_1988/