Hi, I have an 85 RX7 GSL-SE with 1.3 Engine. The car had been sitting for 10 years. I drained and removed the tank. The tank was pretty well tarnished. I cleaned the tank and pick up, replaced the fuel filter and fuel pump, changed cap, rotor, plugs and wires. Changed the oil, filter and air filter. I got the car running and at first it ran great. Now its starting to loose power. Feels like a clogged fuel filter. I replaced the filter with same results. I did a fuel pressure test and the pump is putting 75PSI out. I tapped in at the return line so the pressure is 75PSI through out the rail when the pump is running. The car will idle fine and rev up ok but looses power as you give it more gas. If you mash the pedal to the floor, it will just bog. I checked the intake for obstructions, all was clear. I disconnected the exhaust at the manifold to make sure there was no restrictions, still ran the same. I'm running out of ideas. I suppose the injectors themselves could be gummed up but it will redline sometimes at cold start up and get worse the longer it runs. Any ideas?

Thanks, Ryan

 

make sure exhaust and cats are not blocked!!

 

engine will need some back pressure to run well so verify cats arent blocked and hook up exhaust to engine.

 

Does the car still have the port valve actuators installed? Ive seen some gsl-se's that have them removed. They open the 5th and 6th ports around 3500 rpm or so. If the ports are stuck open or closed it may run funny.

 

75PSI? That sounds way too high. Stock fuel pressure on these should be around 35PSI. I'm not a 1st Gen guy but I would start by trying to lower fuel pressure somehow.

 

Im looking at haynes manual now for gsl-se 13b, fuel pressure is 49.8 - 71.1 psi. (a lot more than other 1st gens) Your gauge may be off a little I think your pump may be fine.

 

Also - if your problem is still not resolved - check all your vacuum lines, make sure their all connected and well seated

 

does the car have any modifications?, has there been any work on the manifold? would help to know condition of engine, etc

 

Everything is stock, car has low miles. Was a good running car prior to sitting for 10 years untouched. I initially drained the fuel, new filter, pump and tune up on engine. Got it running and it seemed to run good. Took it around the block, had plenty of power. Took it for a short drive later and all was good for a few miles then it gradually started to loose power. Acted like a fuel restriction. Couldnt give it full throttle. The farther I went, the less throttle I could give till it would only idle. Thought maybe stuff in tank, changed the filter again with no change. Pulled the tank to find it was tarnished inside, the pick up was fully tarnished in thick sludge. I soaked the tank and pick up in Methyl Ethyl Ketone (MEK) and flushed it all out till it was spotless. Put it all back together and still had same results. I just did the fuel pressure test to verify something else could be plugged with the tarnish but the pressure was spot on. Could you build pressure and still not have enough flow? Could the lines be semi plugged? Thanks for the tips!

 

Any thoughts?
Thanks.

 

If fuel pressure is high and you expect the engine still is not getting enough fuel a clogged injector or carb jet sounds like a reasonable culprit to me. If the fuel pressure isn't getting partially released into the engine, it explains the high pressure and the engine being starved of fuel.