Im new to the RX7 world and I have recently purchased an 84 GSL with 81,000 kms on it. Anyway my problem is that it loses power on the bottem end, it will be fine and then seems to bog down. It was doing it at high rpms to but I added some fuel treatment and it seemed to work better at higher speeds. My mechanic doesn't know much about about 7s but he cleaned the carb and he said it was shooting gas out of all of the ports. Could it be something other than a carb problem? Your help would be greatly appreciated. Also the gas guage doesn't work, checked the wiring diagrams on the site but it doesn't list one for the fuel guage.
Thanks in advance
Gordie

 

The 84 GSL-SE was EFI. Didn't know that a carb 84 GSL existed in the USA. If it is a carb tell your mechanic that there is not that much special. There is probably some dirt in a low speed air bleed or emulsion tube.

 

The 84 GSL-SE was EFI. Didn't know that a carb 84 GSL existed in the USA. If it is a carb tell your mechanic that there is not that much special. There is probably some dirt in a low speed air bleed or emulsion tube.

Just noticed you are in Nova Scotia. Don't know what they have there.

 

The GSL (not the GSL-SE, which has FI) is carbed. Is it bogging down at high RPM regardless of speed, but fine at cruise rpm (ie: under 3500rpm) on the highway? If so, replace your fuel filter. It's located under the car on the drivers' side just forward of the gas tank and just aft of the electric fuel pump. Cost is under $5 at Napa or other aftermarket supplier, and install takes less than 10 minutes. Anybody can do it.

This problem may be caused by something else, but since the filter is so inexpensive (and should be replaced from time to time anyway) it's the best place to start.

 

The GSL-SE was only available in 84 and 85, but it was a very small number of the RX-7s sold. The GSL-SE used the fuel-injected 13b, and all other models during those years used the 12a.

But there were 12a GSL's in 84 and 85.
Just to clear things up.

 

So far it is still doing the same thing, idles great, just loses power and then runs fine and then loses it again. Very intermittent but also very annoying. More help would be appreciated. Also still cant find the wiring diagram for the fuel guage.
Thanks
Gordie

 

So did you change out the fuel filter. 99 percent of the time thats the culprit. I've also got into the habit of not letting my tank get lower than half a tank to try and avoid plugging up my filter with "stuff"

 

Changed fuel filter, no help

 

When you say losing power is it shutdown down completely? I had a similar problem that was a electrical short between the lead coil and the igniter. It would run for approximately 30 seconds to a minute and would shutdown. However, would restart with no problems.

 

No it doesn't shut down it just loses power, if I let of the gas and floor it sometimes it doesn't bog down sometimes it does. Could it be electrical? It is intermitent and only does it in the lower rpm area.

 

I have an '84 GSL, its a creme color... ...so im gonna paint it dark silver. Anyways, im doin a bunch of mods to it and i wanna go turbo, but im gonna hold off a while, it should be up and running tonight, i will post pics of it when it does.

 

There's one other place to look that will only take 1/2 hour or less. (best to eliminate the least-expensive possibilities first):

Remove the drivers' side storage bin. Under the carpeted bin you'll find a plastic electrical junction with wires protruding from it. One of these circuits is the electric fuel pump circuit.

What sometimes happens is that moisture gets into this area and will intermittently short out the junction (causing intermittent stalls and/ or loss of power) until the arcing has destroyed the connection. At that point the car will not start, period.

If you find moisture in this area (a distinct possibility if rust has eaten a hole from the rear wheel well to inside this area) inspect the connection. If it appears ok except for the moisture dry it out with a blow dryer, waterproof it with plastic bag material and/ or electrical tape, and tape it up out of the way of any water that may pool there.

If the plug is arced and burned, replace with one from the auto wrecker for peanuts.

If the area is dry and there's no sign of arcing this is not the problem.

The problem you're describing sounds definitely fuel related, but when you say you're intermittently losing power does the engine:

a) bog down as though out of gas, with rpms remaining smooth but decreasing steadily?,

or b) begin to mis-fire, run rough, and sound like it's only running on half an engine?

If a), fuel delivery is the culprit. Your next cheapest experiment would be to check the wiring contacts on the fuel pump. If the connections look ok, replace the fuel pump (located just ahead of the filter under the car) with a cheapie from the wreckers).

If that doesn't solve the problem you should now consider the carb and/ or carb-related emission crap. If not well-versed with this area you may wish to have a Mazda-competent person (ie: not likely to be a mechanic at a Mazda dealer--- look for an independant shop specializing in RX7s) take a look at it.

 

Thanks aviator alot of great info there. Hopefully one of them will help. As far as it bogging down and losing power, if I remember correctly the rpms do remain constant but the car does slow down. When I first got it, it would hardly make it up a hill in 4th gear, I added carb cleaner and now I have the power in 4th and 5th but 1st , 2nd, 3rd is where it seems to lose it. At times I have had the rpms up to 4 grand in 1st and it just jugs along and will correct itself and it will be fine and them sometimes it will be fine but lose it in second. It's driving me nuts.
Gordie

 

hmmm ... I would 1) check your ignition system .. plugs, wires, coils, etc ... If you say it does that arround 4000 , isn't that when the 4 barrel kicks in ? maybe the 2 secondaries have problems in them ? gas not getting to engine sufficiently ? these are all common things to check out ...

 

Right now I'm willing to check out my ex wife if I thought that would help. Thanks for the input everybody. Still open for suggestions though.
Gordie

 

Also, check your secondary on the carburetor.

 

Still have the problem, we have tried everything. Please help
Thanks

 

dude check your fuel pump. Go get a compression test and then go rip out the rats nest and also check the cats. How does it rev up? Like does it sound like it's coughing and weezing?

 

No revs up great, idles great, no backfires etc. Like I said I'm new to the RX7 game. I keep seeing rats nest, and ripping them out. What is a rats nest and what do you gain when you rip it out. Also does anyone have an explaination on how to do it.
Thanks

 

Found the problem, the exhust was partially plugged and I had a small leak between the fuel tank and the gas filter which wasn't allowing enough fuel to reach the bowl and it was sucking air.
Thanks for all of the suggestions, I learnt alot in the last little while and so did my mechanic.
Gordie