1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

12a Dies when I come to a stop.

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Old Jun 14, 2010 | 03:55 PM
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12a Dies when I come to a stop.

Ok. I bought an 83 RX7 a few days ago and got it running ok. It has some minor issues that I can work out later but right now this is what I need to get figured out.

When I come to a stop 90% of the time the engine will sputter and die. I thought I had the problem temporarily fixed by disconnecting the brake booster which was causing a vacuum leak when I hit the brakes. Now the idle doesn't change when I pump the brakes but it still dies when I decelerate. I've checked all the lines for vacuum leaks, fuel leaks, anything. I'm pretty much at a loss. Anyone have any ideas?
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Old Jun 14, 2010 | 04:10 PM
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Try setting the idle speed and mixture according to Sterling's method: http://sterlingmetalworks.com/tuning_the_nikki.htm

If that doesn't fix the problem, then let us know.




.
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Old Jun 14, 2010 | 11:39 PM
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I was only able to adjust the idle. It helped a bit. Now it only dies when I brake hard. I cant adjust the mixture because it has a metal cap over the screw. Any way to remove the cap without removing the carb?
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Old Jun 15, 2010 | 08:44 AM
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Just rip it off with some pliers, then back the screw off a few turns, sounds like your idle is on the lean side

also what you have decsribed could be the carby icing up combined with a marginal idle. driving at moderate speeds consistently (not stop start) in cold weather will upset the carby if the air cleaner snout has had the flapper valve removed, setting the idle higher and a little richer (eg 1krpm) should prevent it dying tho. good luck.
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Old Jun 15, 2010 | 01:59 PM
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I adjusted the carb some more and its working a lot better. I do have a leak around the accelerator pump and it doesnt seem like its working. I'm sure its all dry and cracking from sitting so long. I'm going to try to find a carb soon that I can rebuild. Is there a difference between the years? If not then I can get the carb from the 79 thats at the junk yard. Thanks for the help everybody.
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Old Jun 15, 2010 | 10:09 PM
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Originally Posted by Ferrariferg
I adjusted the carb some more and its working a lot better. I do have a leak around the accelerator pump and it doesnt seem like its working. I'm sure its all dry and cracking from sitting so long. I'm going to try to find a carb soon that I can rebuild. Is there a difference between the years? If not then I can get the carb from the 79 thats at the junk yard. Thanks for the help everybody.
there are slight differences but it will bolt on to your 83 fine
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Old Jun 16, 2010 | 02:32 AM
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Good to know. Hopefully its still there and I can pick it up this weekend. Who sells the best rebuild kit?
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Old Jun 16, 2010 | 08:05 AM
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try letting out the clutch when you stop...

I KID I KID

sterling, that same guy you followed when adjusting the idle is a nikki god. While you're rebuilding you should
A)send it to him for some heavy performance mods
B)Rebuild it yourself but follow his instructions for making it awesome.
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Old Jun 16, 2010 | 08:07 AM
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Check the fule filter!!!!!!!!!!!!!!Bob
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Old Jun 16, 2010 | 08:11 AM
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Originally Posted by Ferrariferg
Good to know. Hopefully its still there and I can pick it up this weekend. Who sells the best rebuild kit?
Autozone are good, sterlings site recommends the 96-555, cheap too.. They told me the manufacturers aren't makingthat model any more but there shouldbe a few here and there I guess.. I use the 96-462 but these are missing a few washersand split pins
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Old Jun 16, 2010 | 09:58 AM
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Fuel filter was already replaced. The old one was so bad the it was actually leaking.

I wish I had the money to send it to sterling. I went through his page and I keep reading about his work on here. I plan on cleaning up the engine as much as possible while still keeping it driveable and I want to keep the AC. It still works so no reason to get rid of it. I was also thinking about taking the whole motor from the RX-7 at the junk yard and doing a street port and a rebuild but I have another motor in the works so that will have to wait.

Thanks again for the help everyone.
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Old Jun 16, 2010 | 12:06 PM
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The carb kit at Autozone that you want is like $28. I just bought one about 2 months ago, and it had everything that I needed, including the new metering ***** that Sterling talks about. I followed his write-up religiously!
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Old Jun 16, 2010 | 12:50 PM
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I'll definitely be following Sterlings advice when I do the rebuild. Its great to have a write-up like that. The only other carb I've rebuilt is a weber 32/36 for my dads 260Z.

I hope having a rebuilt carb will solve the problem. The car runs great and idles well. It just doesn't like to return to idle and not having a working accelerator pump can be bad when pulling out in traffic and the car dies.
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Old Jun 16, 2010 | 01:19 PM
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I understand the money issue, but you should at least convert to mech. secondaries.
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Old Jun 16, 2010 | 01:29 PM
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I've seen that mentioned a few times. How is that done?

I cant seem to find how to remove the rats nest. I saw something the other day but forgot to bookmark it.
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Old Jun 18, 2010 | 07:27 AM
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Rats nest removal can be found in the Gen 1 FAQ thread.
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Old Jun 18, 2010 | 11:58 AM
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The mech secondary mod can be found there as well...
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Old Jun 18, 2010 | 01:05 PM
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So the car decided it didnt want to start anymore. I dont know what the problem is. Someone mentioned the fuel pump but I can still hear it ticking (not sure if its supposed to tick) but I figured that since it wont start I might as well take advantage of it and pull the carb and emissions stuff. The writeup for removing the rats nest is excellent. I have everything off now. I just ordered the carb rebuild kit (had to get it from the HUB). Hopefully I can get it done tonight. Its amazing how much nicer the engine looks. Now I need to make up the block off plates and clean the rest of the engine with degreaser.
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Old Jun 24, 2010 | 02:49 AM
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Ok. I rebuilt the carb and it ran ok but I still had the same issue then it decided to not start again. I let it sit for a day then I messed with it some and got it to run and spent the day retuning the carb and had it Idling smooth and I fixed the problem with it dieing when I stop. I needed to turn the mixture screw some more. But now it wont start again. Does anybody have any idea what could cause it to not start? It runs great when it does run but once its sat and cooled down it will just crank and try to run but it just wont start.
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Old Jun 24, 2010 | 03:49 AM
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Originally Posted by Ferrariferg
Ok. I rebuilt the carb and it ran ok but I still had the same issue then it decided to not start again. I let it sit for a day then I messed with it some and got it to run and spent the day retuning the carb and had it Idling smooth and I fixed the problem with it dieing when I stop. I needed to turn the mixture screw some more. But now it wont start again. Does anybody have any idea what could cause it to not start? It runs great when it does run but once its sat and cooled down it will just crank and try to run but it just wont start.
check your float levels, often the bowls flood, but if you read Sterling's guide im guessing you did his trick on the needles as well?

when starting you should pump the throttle once or twice then crank with the throttle partly open and hold it open for a while, unless you use the choke

beyond that you could check the ignition.
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Old Jun 24, 2010 | 10:39 AM
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Have you checked the timing?
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Old Jun 24, 2010 | 01:25 PM
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Ugh. I came home for my lunch break and decided to try to start it after it sat over night and it started up but idled really rough. I shut it off and added some coolant cause I remembered that it was a little low and then it wouldnt start. I adjusted the floats but I guess I missed the trick with the needle. Ill read up on that later. The timing was perfect for both leading and trailing.
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Old Jun 24, 2010 | 02:15 PM
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Adjusting the floats is usually a step towards failure. Unless the carb was tampered with before, or dropped, they never need adjustment. Adjusting them usually just leads to more issues, as it can be very difficult to get them right.

P.S. If you had done your research at Sterling's site like I told you to, you would have known that!
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Old Jun 24, 2010 | 05:19 PM
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The floats were not level or anywhere near where they should be so I adjusted them to proper specs and both bowls have the perfect level of fuel.

I'm about to go pull the plugs in a couple minutes. last time i pulled them they were pitch black and soaked in gas. They are brand new plugs so they shouldnt have that much carbon on them already should they? While I have them out Ill test the coils as well.
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Old Jun 24, 2010 | 11:49 PM
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my car was doing the same thing as well, when i bought it and after a rebuild too, it took alot of tuning, float adjustment and make sure your float vent is not capped.
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