RX-7 starts sometimes then dies a few seconds later
 

OK so this is my second post on getting my 12 year sitting RX-7 running. The issue I am having now is that when I turn the key, the car attempts to turn over and every once in a while it will start but it dies a few seconds later. One thing I noticed is that my clutch has no pressure and I have checked the clutch fluid, its fine and no fluids are dripping under the car. Any idea on why my car won't stay running and why the clutch has no pressure? If so mind explaining a resolution?

Did you fix your Wet engine problem yet?
also if your clutch has no pressure then you are looking at a Hydraulic leak.
Do the WHOLE system replacement( master,slave.If the line is good,great).
It will cost you about 100 bucks.
If you "half ass it" you will blow the "other Hydraulic part" out in short due time.(Ie get master the old 20 year slave fails afterwards).

I am not sure what you mean by "wet engine" problem because I previously had an oil filter problem which I resolved successfully. And your recommending a full clutch replacement? Someone told me earlier that the clutch can take around 20 minutes of pumping to create pressure.

Woops Sorry.I was thinking of someone else who had de-greased their engine and now it won't start.
My Bad.
.........
Now as far as FULL clutch replacement NO.just the Parts that hold fluid.The master clutch cylinder and the slave cylinder.
Don't listen to that "20 minutes to build pressure crapola"!
But,Lets Just assume this is true though,and play along with it..
You get in your car,Pump 20 minutes,get the car to shift into gear..drive off ..Pump another 20..shift into second..
Sitting at the stop light,You are pumping like crazy.Lady calls the Cops and says there is a degenerate doing unspeakable things inside his vehicle..appears to be having sex with is steering wheel.Yelling: "come on Baby,come on Baby..Dammit"!

.....sorry I had to....I am only human!...........

If the Pedal doesn't create pressure after proper bleeding then it is not an Operational system.Meaning it is NOT working as it should.
Either you get pressure or you get NOTHING.
If you do not get pressure,something is wrong.Bad master,bad hose, a leak,Bad slave cylinder.That is to name some "hydraulically".
..Note: sure you can have a system that is spongy,but that means air.Air means it is not Bled properly.And if Air is in there,How did it get there?
You didn't touch anything?It just suddenly happened ?OK,Then the parts are faulty,and introducing air to the system..
A Clutch may operate with air in it,BUT at that very moment you think it is OK,..BAM!,that air can move in the system,create HELL, and your foot goes to the floor,no shift for you.

Did you try starting it in neutral with the gears disingaged?
That would eliminate the drivetrain as a source for your car not holding an idle after it starts.

I tried starting it in neutral and it still would idle for a few seconds then just die. I think whats happening is since the clutch has no pressure, the car turns over then stalls because of no pressure in the clutch then dies. My other theory is that fuel is not getting to the engine correctly but the fuel filter is full of fuel.

Jumper the fuel check connector.

What do you mean jumper the fuel check connector?

Check the MAF Sensor at the intake box.(Location: Bottom right of the box) If the retaining spring is gone or loose, the plug will slide out eventually and cause this 2 second idle and shut of sequence. Give it a push it and post your results!! :)

Let me go try this, I do have to find it first though, any pictures on what it looks like? Also could my clutch having no pressure be causing my car to stall after a few seconds?

That's weird. Sorry no help

Post #35

https://www.rx7club.com/2nd-generati...1012775/page2/

The engine should not care about clutch pressure.

if there is no fluid leak.. surely there are few air pockets in the clutch circuit...about the engine u can check the fuel filter ;)

The clutch needs bleeded I believe so I will do that and the engine, the fuel filter is good, no leaks. I am going to check the MAF tomorrow because like I said, every once in a while it would finally turn over but die seconds later.

Jumper the fuel check connector.

I will try it tomorrow but for reference, what exactly will jumping it do or what am I testing for?

I unno about the clutch pressure, it could be that your clutch cylinder is bad. I dont have pics buts a big plug that goes into the right side of the intake box. It is fairly easy to see

What model year/trim level are you working on? And what have you done to the car to get it running after it sat for 12 years?

1983 GSL RX-7, I have replaced the oil, replaced the oil filter, put new gas in, replaced the battery, added clutch fluid, added cooler fluid.

Glad you clarified that. The check connector discussed above is on 86+ models, so you'll have a helluva time finding one on your car. :D Also, do you know if it was running when it was parked?

Check the fuel level in the float bowls before you start it and after it dies. There are sight glasses visible from the front and rear of the carb that should sit at half full all the time. If it doesn't, the fuel filter needs replacing anyway and the carb should be cleaned or rebuilt.

is your fuel pump anygood?

I actually have been working on the car all day and noticed when I was pulling the choke in my car it actually wasn't moving the throttle, I had to jam the throttle so little air could get in and my car is now starting and staying idle. The problem is that the choke doesn't adjust the throttles position so I am going to need parts to replace that. I also noticed when it was idle, when I pressed the gas pedal, there was 0 pressure and the pedal nearly sank to the floor. I bleeded the clutch slave cylinder as well and I could create pressure so I am just going to replace the master and slave clutch cylinders.

I'm not much of a knowledge-base on these things, but from my limited experience it sounds like the issue is with fuel delivery. I'd second those who suggested inspecting your fuel pump.

I don't think the squishy clutch has anything to do with the dying after starting problem you're getting (in my experience, that'll just prevent starting altogether if it's an issue). Check the lines for leaks, and if there's no leakage, just make sure your clutch fluid reservoir is filled and the line is sufficiently bled of air bubbles.

As for replacing your entire clutch hydraulic system, I live by the old proverb: "If it ain't broke, don't fix it." I replaced just the hard line and soft hose in my FC and so far everything seems to be holding up fine. If one cylinder cracks, replace both cylinders. If the cylinders are in decent shape (no excessive rusting, no cracks, no chips), I wouldn't worry about replacing them right away.

Ok, so 83 RX-7 with a carb.
Is it the stock carb?
Assuming yes for the moment, the choke cable pulls a link on the carb that closes the choke blade and opens the throttle slightly via a mechanical linkage on the side of the carb.
You state the accelerator sinks to the floor so that might indicate the throttle cable is disconnected or broken, pretty easy to check.

It would probably be a good idea for members to state what kind of year/model RX7 they are working on a bit before the 18th post of the thread, I'm just saying... :)

As for checking the fuel pump/delivery, on the carb models the fastest, quick and dirty check would be to pop off the delivery line (the larger diameter rubber hose) at the carb and stick it into a pint size bottle while an assistant turns the ignition to the 'on' position. The fuel should flow freely and vigorously into the bottle at a rate that will mostly fill it in say 10 to 15 seconds. You can also see how clean the fuel looks, and if there is water coming through (water is more dense than gasoline and will sink to the bottom of the bottle) and you can smell the gas to see if it's fresh or stale.
If the fuel flow is weak the first thing to try is a new fuel filter. Before you change it shine a bright light through the bottom of the filter and look for excess dirt and debris, but also for water in the filter, again the water will be the bottom layer, with gasoline above it.
Back up at the carb, you can also terminate the fuel line with a pressure guage and check the absolute fuel pressure.
DO THIS WITH A COLD ENGINE/ EXHAUST SYSTEM, if you spill gas on a hot engine there will be fire.....

Next, check the fuel level in both bowl windows at each end of the carb, correct level is halfway up the window.
With the key on, engine off, look in the top of the carb, there should be no fuel dripping down through the venturis, if there is, time for carb O/H.
Next, rotate the throttle from closed to wide open and look in the smaller primary venturis and see if both sides are getting a squirt of fuel from the accelerator pump nozzles.

It's always good to run through a list of the basic functions to confirm functions before you start changing out parts.
Remember that in order to run an engine needs to crank (AKA- turn over), have compression, have spark and fuel.
Too many times parts get changed before basic functions are confirmed, and that can muddy the diagnostic picture.

One more thing, cranking, or turning over is what the engine does when the starter is operated and the engine spins.
Firing is what happens next when the spark ignites the fuel and the engine starts running.
A simple thing, but one that is too often misstated.

Next, there's a list of things to check on the ignition system once fuel is confirmed.

And then after all that when you have it running you can look at your clutch pedal issues, try bleeding the system out with fresh fluid first.

Divide the problem into parts and solve each one individually.
Don't be a 'parts changer', it get's expensive very quickly and you generally don't learn WHY the problem occurred.
If you don't want to understand 'why' then just pay someone who does understand how it works to fix it.

Good luck, and I hope this helps you understand your carb a little better.

Thanks for the info, I will take this into deeper consideration today as I try to assess some of the issues. I went to a parts shop earlier and he said that accelerator issue may be linked to a bad spring but I think your right in saying that the throttle is not actually being pulled.