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-   2nd Generation Specific (1986-1992) (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/)
-   -   Fuel Pump Going...what brand do you suggest to replace it with? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/fuel-pump-going-what-brand-do-you-suggest-replace-907298/)

cis2711 06-05-10 06:20 PM

Fuel Pump Going...what brand do you suggest to replace it with?
 
I'm looking on Rockauto.com at like 7 different brands and I'd like some feedback... My rx7 has trouble starting when it's hot and it is fuel related. After like ten minutes of trying to start it after coming out of lowes today it finally idled and I drove away. I'm certain it is the fuel pump..23 years old after all. Fuel filter was changed a month ago.

cis2711 06-05-10 06:20 PM

1987 N/A btw

RotaryRocket88 06-05-10 06:24 PM

Hot start problems are not caused by fuel pumps. Read through this thread: https://www.rx7club.com/2nd-generation-specific-1986-1992-17/looking-car-has-hot-start-problems-499744/. The stock start map is excessively rich, which leads to flooding. A search for "deflood" or "flooding" will turn up many threads on the subject.

Hypertek 06-05-10 06:24 PM

Check out the fuel strainer/sock.

cis2711 06-06-10 10:12 PM

hmm so it was flooded? that is why it wouldn't start immediately? It was trying to turn over as in it indicated not getting enough fuel but I guess you could be correct too. So when I fuel pump goes it just....goes and the car will not run at all after it goes??..

jjwalker 06-06-10 10:17 PM

Check the o-ring on the pump outlet, and also the fuel sock as hypertek said.

RotaryRocket88 06-07-10 12:05 PM

If it only happens when the engine is already warm, and it starts/runs fine otherwise, I would not be looking to the fuel pump for the issue. A dying pump would create problems while the engine is running due to reduced flow and fuel pressure. If you want to confirm it's actually flooding, try to start it when warm, then pull the spark plugs. If they're wet with gas, that's a sign it's flooded. The "quick-fix" deflooding procedure is to pull the EGI fuses under the hood, crank for a few seconds, replace the fuses, then try to start it with the throttle open.

cis2711 06-08-10 12:18 AM

thats what I was thinking. I'll just pull the fuses next time. If I wanted to replace the pump as a precaution though which brand is FTW??

10yearrx7 06-08-10 01:04 AM

Bad compression will also give you hot start problems.

I've got a walbro 255 and i've had no problems, but a lot of people say they aren't good.

nycgps 06-08-10 07:05 AM


Originally Posted by 10yearrx7 (Post 10044767)
Bad compression will also give you hot start problems.

I've got a walbro 255 and i've had no problems, but a lot of people say they aren't good.

Walbro is not good for stock car because it flows way too much fuel. so instead of Super Rich Fuel trim, it becomes Uber Super Duper rich. :lol:

jjwalker 06-08-10 08:38 AM

I had a hot start problem caused by the fuel pump o-ring. Here's how it works...

Start car cold, starts up great.

Start up warm, wouldn't start first try because PRC solenoid opens and lowers fuel pressure. I had no fuel pressure anyway because my o-ring was bad and all of ther fuel pressure was leaking back into the tank from the o-ring instantly.

nycgps 06-08-10 10:17 AM

you talking about the o-ring at the bottom of the assembly ?

10yearrx7 06-08-10 03:31 PM


Originally Posted by nycgps (Post 10044972)
Walbro is not good for stock car because it flows way too much fuel. so instead of Super Rich Fuel trim, it becomes Uber Super Duper rich. :lol:

Ya but I was running super lean before so the fuel pump evened it out perfect. The car rarely flooded:icon_tup:

LunchboxCritter 06-08-10 11:23 PM

If you would like to rule out flooding being the issue. The next time it happens floor the gas peddle and crank it for 10 sec, let it sit for 5 sec, crank for 10, etc. (this works on my S5, not sure if it works on S4 models) This cuts the fuel and should allow it to deflood itself, and fire.

This works on RX8's as well, and is much easier than pulling plugs, atf, and all the other tricks.

A compression test wouldn't hurt either and is fairly simple to do, if you have someone to help.

RotaryRocket88 06-09-10 01:07 PM

^ Holding the pedal to the floor in an S4 won't cut fuel like an S5, but it will allow more air into the combustion chamber to hopefully start the engine. S4s just need the EGI fuses pulled to cut fuel.

sharingan 19 06-09-10 01:41 PM

Don't even consider an aftermarket fuel pump, especially a 255lph! N/A's run rich as it is, and that pump will only make the situation worse.

Leaking injectors might also play a part, but it really sounds like typical flooding issues here.

Spectrum24x 06-09-10 06:02 PM

i dont mean to thread jack, but i have a related issue, i put an fd fuel pump to replace my stock n/a fuel pump on my t2 swap and ever since its struggled with cold and hot starts, but runs fine

RotaryRocket88 06-09-10 07:46 PM


Originally Posted by Spectrum24x (Post 10048085)
i dont mean to thread jack, but i have a related issue, i put an fd fuel pump to replace my stock n/a fuel pump on my t2 swap and ever since its struggled with cold and hot starts, but runs fine

Have you checked your fuel pressure?

cis2711 06-10-10 06:41 PM

the car died on a back road two days ago.. now it won't start at all. fuel pump must be dead.


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