Well i will try to describe the problem the best i can. I have done a search but
i would like advise that fits my situation more.

I drove my car and it ran great, with no problems. The next afternoon i started my
car as i always do (pulled the choke and it revs at 2000+RPM).

But this time, i gave it gas and it died.
I put it in Neutral, reved it to 2500 RPM and the engine dies.
When i give it gas above 2500 Rpm it dies.

But i was able to drive it home in gear as long as i kept the revs high (hope this
does not confuse you guys, or of it helps to mention it.)

The Car will start and idle at around 900 rpm, but as soon as i give it gas it dies,
at around 2500 RPM.


I changed the spark plugs with new NGK BR8EQ-14, and put a new fuel filter.
and it has not fixed the problem.

What could be causing this and how do i fix it?

...and how can this problem have happened like it did, all of a sudden, from one
day to the next?

I miss driving my Rx-7 so much!!!

Help me please.

 

Do you still have all your emissions equipment? Sounds like a vaccum leak to me.
Check your fuel flow also, Your fuel filter might be clogging up. Also make sure your getting spark at all spark plugs.

 

Yep, sounds like you may have lost your leading ignition (coil or ignitor?). Verify that you have spark on the bottom plugs.

 

Sounds like a bad accelerator pump to me.

If it were a vacuum leak, the thing wouldn't idle.

 

Check your fuel pump too. Mine kinda gave me the same problem. It had a big leak in the metal pickup line inside the gastank leading up to the fuel pump.

 

Ditto

 

I did the Volume test and got 1.50 Quarts of fuel expelled within a minute.

Am going to test for the things you have suggested.

 

Also check the little filter screen in the fuel inlet.

 

Vac leaks mean nothing above 1,500rpm unless they're massively huge.. even then, you wouldn't be able to get it started or idling easily or at all.

My bet is that it's a carb problem. If your fuel pump is providing sufficient fuel and your fuel filter is clean, it's a carb problem.

Why? Because your "gas" pedal is actually controling how much AIR goes through the carb, in a roundabout sorta way. As you push the gas pedal more, the butterflies in the carb open more, allowing more air to be sucked in by the engine. While this air rushes through the carb, it pulls some atomized gas along with it. If you've got too much air and not enough gas coming into that air, you bog/stall. This is why you need a bigger accelerator pump with mechanical secondaries, because if I mash the pedal, I've got all air, practically no gas and it stalls.

All this to say : probably carb related if you're sure the gas is getting there alright.

Jon

 

I would say the accelerator pump or maybe a clogged transition circuit or something like that.

 

Have you checked for spark on the leading plugs yet? It only takes a minute. Since this problem had a sudden onset, I'm reluctant to agree that it is a carb issue. However, if you have proper fuel flow from the pump to the carb, AND your leading ignition is good, then I will happily agree with the carb issue diagnosis.

 

I checked for spark on the Leading plugs and the trailing, and they all have
spark.

The fuel pump passed the volume test. It had more than 1.16 quarts a minute.
Changed the fuel filter.

I even sprayed carb cleaner around the engine to check for vacuum leaks while
it was running and there was no change in the way the engine ran.

..but i press the gas pedal in Neutral and as soon as the engine gets to 2500 rpm,
the rpms drop like a rock and it dies.

I will see if it is the accelerator pump or carburator that is causing the problem.

Wish i new of a good carburator mechanic in my city.
Anyone got a pic of the accelerator pump, i don't even know what it looks like.

I will do a searh on it to start with.

Thank you guys, and keep the information coming please.

 

Take a look at the service manual located in the FAQ section. You will find the ap in there.

 

It could be the AP only if it dies right when you mash the pedal. Is that what happens? When I read the initial post, I thought is was more like, push pedal, bring rpms up, then when it gets ~2500, it dies. Doesn't sound like AP. If you have someone who can help, have them look at the float bowl levels when you do this. See if the levels dip below the 1/2 way mark.

This does confuse me. How were you able to get to "high" revs? What was different?

Maybe something's wrong in the main or transition circuit vacuum signaling.

 

Yeah, i can make it accelarate to 2500 rpm, and when it hits that it dies.
It will not start up again unless i pump the gas pedal before i turn the key.