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-   -   85 GSL_SE leaking fuel injectors (https://www.rx7club.com/1st-generation-specific-1979-1985-18/85-gsl_se-leaking-fuel-injectors-260154/)

Terrel 01-13-04 09:08 AM

85 GSL_SE leaking fuel injectors
 
I believe I have leaking fuel injectors. The car runs fine, but after sitting a couple hours will be flooded. I take out the plugs, blow out the fuel, dry the plugs off and reassemble everything and it will start. Then repeat the whole thing after sitting again. Is there some kind of temp fix that will allow fuel pressure to be bled off back to the tank after turning off the engine?

Thanks.

Steve Shulz 01-13-04 09:30 AM

You have two possible situations.
1) leaky injectors - very probable.
2) your fuel pump is pumping regardless if the engine is truning or not. Also probable
or it may be both

You can put in a fuel cut switch (do a search) by putting a relay or toggle switch (I put in toggle- my fuel pump pumps at all times -grounded wire somewhere). When Im done driving I flip the switch (placed behind the seat storage bin wall) let the car die then turn off the key. When Im ready to go I crank the motor for about 2 secs then flip the switch and away I go. Its a PITA but until you can pull the injectors, or in my case find the wire, it works.

MarkPerez 01-13-04 11:15 AM

Are you sure it's gas on the plugs ?? the injectors don't work untill theres power(running) . do you smell gas under the hood ? try this, turn the key to 'on' all lights across the dash lite up, remove the air cleaner eliment and use your finger or something to push open the flapper door on the MAS and listen....you should hear the fuel pump, pumping and fuel going through the delivery pipe and return tube. It might just be the grommets on and around the injectors and o-rings on the delivery pipe.. flooding,,,mmmmmm

Terrel 01-13-04 11:29 PM

85 GSL_SE leaking fuel injectors
 
Thanks

The spark plugs are full of fuel when I pull them. I have no gas smell under the hood. I once had a leaking pulsation damper but replaced that right away. The way it was explained to me...the injectors are not holding the fuel line pressure when shut off and the fuel slowly leaks in. (Don't know if I quite have that right...) I can crank the engine with the plugs out, dry the plugs with compressed air and the thing will restart, only to flood after sitting a while. The switch suggestion seems like a good idea. I can't afford the price of injectors right now.


Terrel

LongDuck 01-13-04 11:41 PM

Another course of action would be to have the injectors overhauled at RC Engineering for somewhat less than buying new. They may find that your injectors don't pass the 'leak-down' test, however, and will have to be scrapped.

When I replaced injectors in my 84SE with BAP "Cobra" brand rebuilds, they were absolute garbage for $90 each. I sent 5 off to a local injector shop for flow-balancing, cleaning, and testing, and they found 2 that could be used - 2 happened to be off of older cars that were cleaned and tested successfully to flow within 5% of each other. These are the ones in the car right now.

If they leak-down, it's because the internal structure of the injector has failed causing them to not hold the pressure - this will occur while sitting, OR RUNNING, i.e., you will have a rich mixture at all throttle settings, because the injector is actively leaking fuel even though the injector pulse width is not telling it to fire.

Your gas mileage has probably gone down considerably over time, but so gradually that you don't notice it.

In your case, I would expect mileage in the 10-12mpg city and no more than about 13-14 highway because the injectors are pouring fuel straight into the intake, you'll also have a loss of power due to overly rich mixture. Some additional complications may be an eventual clogged cat, or overheated exhaust system, since you're sending a lot of fuel down the exhaust to be burned on the catalysts (assuming you still have them installed).

Best bet it to budget for new/rebuilt injectors and fix the root of the problem. A bypass switch only fixes part of the problem - you will still have problems with stoichiometric balance in the A/F mixture which will rob power.

For the poster that stated he is unable to shut off fuel pressure prior to start - check your fuel pump shunt connector by the airflow meter to see if a careless mechanic may have left the shunt in place. When you short out this connector, it causes the pump to run even though the engine is not running. It was meant as a means of testing the fuel rail and injectors for leaks prior to installation of the entire upper intake tract. HTH,

MarkPerez 01-14-04 03:00 AM

You can always visit your local boneyard and try to find an -SE. and just stick'em in your pockets. i'm not sure if a 2ed gen injector would work 13b, 13b. But be carefull
when unpluging any part of the injector connector(s)

Steve Shulz 01-14-04 06:21 AM

FC injectors are different. The -SE's are 680cc vs 460-550cc. The FC guys like to put ours in there's for an added kick. check this out http://rotaryresurrection.com/injector.html

Terrel 01-14-04 08:44 AM

I do have some power loss and rotten gas mileage. Is there an email address or phone number for RC Engineering I could get? In the mean time I am going to put in a pump cutoff switch so I can drive the car to work and be fairly sure of getting home again.

Thanks

Steve Shulz 01-14-04 09:04 AM

http://www.rceng.com/ they are here in Seattle, you have to request the package to send your stuff in.

Steve Shulz 01-14-04 09:14 AM

These guys are in WA, RC is in LA, sorry. Here is the WA guys http://www.injectorshop.com/


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