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-   -   Having Issues (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/having-issues-885585/)

PwrHungry 02-02-10 01:37 PM

Having Issues
 
I have a 1988 non-turbo FC, I have had troubles with it ever since i bought it. It won't start a lot of the time, like if i drive it for a bit at normal operating temp, turn it off go out to start it half an hour to an hour later it wont start. but if i let it sit for awhile it will start fine. also when i stop to get gas or something and i start it up again it starts but revs up to 3 grand right when its started.

Thanks for reading, hope to get answers soon.

alexdimen 02-02-10 01:47 PM


Originally Posted by PwrHungry (Post 9778788)
I have a 1988 non-turbo FC, I have had troubles with it ever since i bought it. It won't start a lot of the time, like if i drive it for a bit at normal operating temp, turn it off go out to start it half an hour to an hour later it wont start. but if i let it sit for awhile it will start fine. also when i stop to get gas or something and i start it up again it starts but revs up to 3 grand right when its started.

Thanks for reading, hope to get answers soon.

Sounds like you could have low compression, which is the cause of flooding. Start by doing a compression test and getting some numbers.

The 3 grand start up could be the AWS being flaky. This is not uncommon and not a major concern. Does it drop back down if you blip the throttle?

PwrHungry 02-02-10 03:14 PM

Whats the estimate cost of putting in new apex seals?

altec_fc3s 02-02-10 04:54 PM

New apex seals require a complete tear down. It maybe cheaper to buy another engine.

PwrHungry 02-02-10 09:03 PM

yeah i knew it was a complete tear down... But thanks for the help. Now i just need to track down an engine or figure this one out.

alexdimen 02-03-10 02:59 PM


Originally Posted by PwrHungry (Post 9779775)
yeah i knew it was a complete tear down... But thanks for the help. Now i just need to track down an engine or figure this one out.

No, you need to test your compression first. You haven't diagnosed it yet.

boyscout 02-03-10 09:49 PM

I had that problem with my 86 FC N/A. Check for a leak in the intake. I lost my lower nut holding my intake hose to my manifold. It was getting air that wasn't measured by the flow meter and got lost or something. Does it at least try to start but can't and leaves lots of smoke? Try holding the pedal all the way down when trying to start it. Even though it's fuel injected, if it's flooded that will start it enough to clear out.

boyscout 02-03-10 10:02 PM

As for thee 3000 RPM thing it may be a malfunction of the cold weather startup system. Try putting it in gear with the clutch pushed in when you start it. That's where I would start looking. Its too bad when you replace your engine just to find yourself back in the same place you are now. minus what you buy the engine for. If you do replace it I suggest keeping the old one because if it's good you have a backup ready to go. Hate to see a good engine in the junk pile.

1SWEET7 02-03-10 11:11 PM

It sounds like old leaky injectors. Much cheaper to get them cleaned than replacing the engine. Witchhunter is a great place to have injectors cleaned.

PwrHungry 02-05-10 02:50 PM

Thanks for the help guys, I'm going to have a compression test done first but I'm having a hard time finding a place that will do one on a rotary.

PwrHungry 02-22-10 01:02 PM

Is it normal for it to pump out a lot of blue smoke on a cold start? It only does it once in a while.

PwrHungry 02-25-10 05:59 PM

Well I took my car in for a compression test today and.... It failed... I'm broke, so what would be the best option for me? This is my DD so I need answers soon, thanks in advance.

clokker 02-25-10 06:01 PM

What do you mean, "it failed"?

PwrHungry 02-25-10 06:03 PM

It's about 15% below minimum compression on all sides.

junito1 02-25-10 06:09 PM

how many miles on this engine.

AND the the guy who tested it did not provide you with any results on paper?

Black Knight RX7 FC3S 02-25-10 06:19 PM

if using a piston comp tester, take the shrader valve out and crank the engine with the egi fuse out to disable the fuel injectors.
I always look for 3 even pulses with more then 80psi.

PwrHungry 02-25-10 06:20 PM

68,XXX
https://farm5.static.flickr.com/4008...a12b8d48e8.jpg

Go48 02-25-10 06:33 PM

In order to evaluate those results you need to know the engine cranking speed at the time of the test. The numbers cannot be compared with the Mazda specs unless you can normalize them to 250 rpm. In other words, if your battery was a bit weak and the engine cranking speed was say 200 rpm, your normalized numbers would likely be OK. Likewise, if your engine cranking speed was 300 rpm, the numbers would be very bad. See if you can get the engine cranking speed at the time of the test from the tech. Or at least a chart with a time track on it so that you can calculate the rpm.

Looking at the rear trace, it looks like the battery may have been losing cranking power towards the end of the test. Good thing about these results is that there is very little difference between the individual faces of the rotors. At least you can say that there is no significant apex seal failure evident.


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