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-   -   fc rx7 starting and running problems (https://www.rx7club.com/new-member-rx-7-technical-256/fc-rx7-starting-running-problems-1047650/)

Rbas 09-30-13 03:23 AM

fc rx7 starting and running problems
 
I have an 88 10th anniversary that is having a strange running issue. The car will fire up and run and after running for about 45 seconds there is a decently loud click from the engine bay and the car turns off. It's just like you turned the key off. After this happens the car refuses to start but today while I was trying to figure this out it started, clicked, died, then as I'm standing beside the car searching for reasons why it would do this it clicked again. So I got in the car and it started right up. What could be causing this??

misterstyx69 09-30-13 08:00 AM

There is a lot of stuff in the engine bay so can you isolate the sound "AREA" and report back?
It could be a Main Relay,that would be near the Driver's side firewall/fender area.

satch 09-30-13 09:05 AM

For testing purposes unplug the four wire plug from the Main Relay (has two plugs in all). Then jumper the White/Blue wire to the Black/White wire and then the Black/Green wire to the Black/Yellow wire. Then see if things behave in a normal fashion. Don't leave these two jumpers in place too long for they will eventually drain the battery.

Rbas 09-30-13 05:27 PM

Just try to bypass main relay and it won't even start at all now, plugged relay back in and felt it while turning the key on and it does click.

satch 09-30-13 05:36 PM


Originally Posted by Rbas (Post 11586525)
Just try to bypass main relay and it won't even start at all now, plugged relay back in and felt it while turning the key on and it does click.

How many plugs does the Main Relay have ? Are you sure you unplugged the proper relay and jumpered it as opposed to the wrong one.

Rbas 09-30-13 05:47 PM

Two plugs on it, I unplugged the four wire one and jumperd the wires as you said above all it did was crank and no fire, I plugged the relay back in and now it still just cranks and no start

Rbas 09-30-13 05:52 PM

Now the car started..... Did the same thing ran for maybe a minute clicked and died. Click sounded like it came from passenger side of the engine intake manifold area possibly

satch 09-30-13 05:53 PM

Did you jumper the wires from the back of the plug so as to mate well w/the wires in the plug or did you try to jumper the wires from the front of the plug? Both the W/L wire and the B/G wires should have constant 12 volts (no key necessary). Do they?

Rbas 09-30-13 05:59 PM

Both wires have voltage and I did jumper them from the back of the plug, this last time it fired I was going to check my coil signal so I had the leading coil unplugged and forgot about it and it fired and ran like it normally would since I bought it..... There are three wires coming out of these coils two go into the plug and one (I'm assuming ground) is connected to nothing should I ground this? I know this won't fix the random turn off but could be another issue

satch 09-30-13 06:03 PM

The Black wire which is short in length and not connected to anything is not a ground wire. It is a diagnostic wire and used for connecting to a tachometer.

Can you try to isolate where specifically this clicking sound is coming from?

And try jumpering the fuel check connector in case the AFM is the problem.

Rbas 09-30-13 06:07 PM

Clicking I'm pretty sure is coming from somewhere by the throttle body underneath my top mount

satch 09-30-13 06:12 PM

The intercooler might be shorting the alternator output wire but that shouldn't cause the car to die and then later fire back up. The clicking sound might also be coming from one or both of the primary injectors.

And the car should run really rough w/o the lead coil and run much better with it.

Rbas 09-30-13 06:53 PM

So I pulled the top mount off to search for stuff, checked my tps and it was way out of spec. Adjusted that and the car starts and stays running now but hunts at idle. Also it has always run a little rough so I decided I'd try and unplug the leading coils while the car was running and there was no change in how it ran. So how do I ho about testing these coil packs and what about the hunting idle? New tps I would imagine.

satch 09-30-13 07:16 PM

The Green/Red wire of the TPS should be set to 1 volt w/key to on and the engine as hot as it can get (20 minute drive should do it).

You should unplug the trailing coil and see if it will start and run w/the lead coil only. You should also check for spark from the lead coil. Unplug a spark plug wire from the bore and place the wire right near the bore and w/the engine turning over you should see spark. Also, the coil igniter needs to ground through the fender so it needs to be mated to the fender properly.

Rbas 09-30-13 07:44 PM

Alright both coil packs are working, I started the car with the trailing coils unplugged and it ran. Car has high idle, around 1500rpm and the idle is rough. Hunting is less intense now and stops after being run for a bit. Getting close now, I'm going to re check the tips, what else would you suggest?

Rbas 09-30-13 07:46 PM

Temp gauge also does not go above one quarter of the way up not sure if that's normal or to cold causing my high idle

satch 09-30-13 07:53 PM

1/4th on the temp gauge is how it should be.

1500 rpm is normal right after a cold start but w/time it should slowly drop down to 750 rpm. After properly setting the TPS you can try pressing upwards on the front throttle linkage to see if the idle speed drops.

Rbas 09-30-13 08:04 PM

Car fires every time now, the hunting is gone since I set that wire to one volt but the car still idles at 1500rpm and is at full temp. Which part of the linkage are you talking about? You can't get to much of it with the top mount on. Car also seems to have a slight miss at idle

satch 09-30-13 08:34 PM

That's the problem of having a turbo. I'm speaking of the throttlebody linkage which rests upon the TPS. If the throttle cable itself is too tight that could cause a high idle and the same things goes for the cruise cable. The Fast Idle Cam could also be malfunctioning and an improper timing could also contribute to a rather high idle.

Rbas 10-01-13 02:31 AM

So I decided to take the car out since it was firing up every time at the shop today. Drove it for a couple hours and ran great no issues and made good power. Turned it off and started it several times while I had it out as well. Then it happened again I pulled into a parking lot turned it off and no start. Same as before just cranks but no fire. Unsure where to go from here now I thought I had the no start issue tackled....

satch 10-01-13 08:52 AM

The car doesn't really like being turned on and off especially when the engine is hot as this is when flooding is most likely to occur. It's a sign of an old engine. Leaky injectors could also contribute to this.

Rbas 10-02-13 01:20 AM

Okay so it would be worth it to get the injectors sent away and serviced? The car is old but has low miles 137, 000kms (85, 625 miles). Any other areas I should look at to solve the flooding issue?

satch 10-02-13 09:19 AM

If you're willing to remove the injectors and pay to have them cleaned then it's always a good idea. And testing compression would be another good idea. And making sure the engine fully warms up before turning the engine off is a good idea as well because the engine can easily flood when the engine doesn't reach operating temp. And repeatedly turning the car on and off just to see if it starts is something which should be avoided. And perhaps getting your ECU chipped by RTEK so it has the deflooding procedure built in might also be a good thing to do. Lastly, turning the car on w/just the key is best and not pressing down on the throttle.

Rbas 10-02-13 07:05 PM

Just tested compression and it was 90-95 psi on both rotors, needless to say I'm not to impressed haha. Rebuild time? If so I would get injectors done and what not at that time. Also would the chipping of my stock ecu still work since this car had an Hks PFC fcon in it. It still runs the stick ecu then the fcon just goes in between to adjust the fuel mapping.

satch 10-02-13 07:30 PM

Not familiar w/your aftermarket component but I don't think it has the deflooding procedure. And 90's compression is not poor.


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