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1990 Rx7 No spark

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Old 06-17-13, 01:04 AM
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Angry 1990 Rx7 No spark

I'm new to the forum and new to rx7's. I picked up this rx and it wont start no spark. Guy that had it before me drove it up to my buddy house, shut if off and now it wont start. checked the coil its getting 6.8 volts with the key on. Same as my other rx and it runs fine. Where should I start?

Thanks guys
Old 06-19-13, 04:50 PM
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OR 1990 rx fc CAS qustions.

So I have a 1990 rx7 fc I got it from a guy cheep said it wouldn't start. I found it was not getting spark. I had a parts car so I replaced both coils Didn't fix my problem. Replaced my CAS and boom, Fired right up. It only runs for about 3 seconds then dies. You can't give it any gas or it will die instantly. any ideas?

Thanks in advance.
Old 06-19-13, 05:09 PM
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Try jumpering the fuel check connector.
Old 06-19-13, 07:41 PM
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Last time I tried that it blew a fuse. lol but I'll give it a shot.
Old 06-19-13, 07:45 PM
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Originally Posted by Ace6913
Last time I tried that it blew a fuse. lol but I'll give it a shot.
Jumpering the check connector turns the pump on w/key to on. Normally, the pump does not do this. If you have a problem w/the AFM then the jumper overrides this possible problem. The fuse should definitely not blow and if it were to then you have an obvious issue. Was it the 15 amp Engine fuse which blew?

And a vacuum leak can cause the engine to conk out.
Old 06-19-13, 07:46 PM
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Wait, what is the Fuel check connector. And how does one go about jumping it.
Old 06-19-13, 07:51 PM
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I did notice that when I turn the key on the pump comes on but then clicks off. (I thought that was weird because my other rx dose not do that.) Sorry i was talking about something different I read a post once on how to jump the fuel fuel pump and that blew my fuse. Is it possible that i didn't install the CAS correctly and messed up the timing?
Old 06-19-13, 07:51 PM
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Post #8 https://www.rx7club.com/new-member-r...oblem-1038568/

Take a piece of wire and bend it into the shape of the letter U and bridge/connect the two wires in the connector to each other.

An incorrectly set CAS will prevent the car from starting.

Last edited by satch; 06-19-13 at 07:54 PM.
Old 06-19-13, 07:54 PM
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Sorry I'm doing 1000 post a minute but also i noticed that pressure builds up where my dipstick is and if i pull my dip stick out it relieves A LOT of pressure.
Old 06-19-13, 07:57 PM
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Originally Posted by Ace6913
Sorry I'm doing 1000 post a minute but also i noticed that pressure builds up where my dipstick is and if i pull my dip stick out it relieves A LOT of pressure.
I wouldn't know about this.
Old 06-21-13, 01:33 AM
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Looked all over for the Fuel check connector to no avail. I even looked in the book and haynes said it was on the driverside rear shock tower. I found what they where talking about but it was a 4 plug. also I got it started today and if I kept it revved up to about 4k it would run. but very poorly and backfiring a ton.
Old 06-21-13, 02:14 AM
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Is this a non-turbo? There really should be no good reason for a pressurized crank case. That could be a bad sign of things to come.

The fuel pump test connector often hangs out in the region behind the air box and near the pressure sensor mounted on the strut tower. It is NOT a green connector, it is yellow. That usually helps make it quite easy to find.

However, if the car runs, and stays running if forced over 4k RPM, then it is quite unlikely it is the fuel pump.

So, let's start over. There's a number of different threads that appear to be merged here. What exactly is/was wrong with the car in the first place and what has been done since? I know there's mention of installing a new CAS. Are you sure this is installed correctly and the engine was aligned to the -5 degree mark (first mark on the right?) when it was installed? What condition are the spark plugs in?
Old 06-21-13, 10:43 PM
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Non-turbo, I figured it wasn't good cus I noticed water in my oil as well .
I was not getting spark, changed out the CAS got spark, got it to run ok now if I have the CAS fully advanced. but still stalls quite a bit and backfires.
Old 06-21-13, 11:09 PM
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You could have the CAS off a tooth (or more). Turn the engine over until the first mark (on the right) lines up with the pin coming out of the front cover. Pull the cover off the top of the CAS. Line up the mark on the CAS with the tiny divot on the bottom of the CAS. Now, hold the gear in place aligned to this mark so it won't turn, and lower it so that the locking nut is roughly centered in the adjustment area. As you lower it, you should feel the gear want to turn ever so slightly, instead of letting the gear itself turn gently turn the CAS in this direction, and you should end up with the locking stud maybe 1/3" the way over and you should be pretty much spot on. Give that a try and see if it helps any.

Also, check the condition of the plugs, and make sure the plug wires are routed correctly.
Old 06-22-13, 01:09 AM
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Thanks a ton man I'll give it shot, Could the milky oil be from it sitting about 6 months in oregon? it pretty humid and rains a lot here.
Old 06-22-13, 01:20 AM
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It's a possibility. Another thing to do is check compression. This should almost always be the first diagnostic step for anything on an RX7.

Hard to start? Compression check.
Won't start? Compression check.
Idles/rev's like poo? Compression check.
Headlights don't go up? Compression check.

It provides so much useful information in eliminating the source of great frustration. If compression looks good, then you can move on and do more diagnostics.
Old 06-22-13, 01:58 AM
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lol one headlight doesn't go up, I better do a compression check! no, I should of mentioned that the first thing i did before even getting the car was a compression check both rotors where at about 90 psi. I'm not really diggin this whole rebuild thing.
Old 06-22-13, 03:05 AM
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Well, at least we know that's not the cause for the headlight being stuck... but not a bad place to start.

Anyway, double check the CAS position, once that's good to go you're going to need to go intake leak hunting. If you've got compression, decent plugs, and good fuel, that's usually a good culprit of a car that won't stay running. (A good way to test this theory is by pressing on the AFM flapper with your hand and holding it slightly open to compensate for the vacuum leak, usually you can get it to run smooth/drop the idle down).
Old 06-22-13, 08:09 AM
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We gotta compression Check Sonic!
90's don't have the Flapper..they are the cone type AFM..
Old 06-22-13, 12:50 PM
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Originally Posted by misterstyx69
We gotta compression Check Sonic!
90's don't have the Flapper..they are the cone type AFM..
Yeah, I have a bad habit of calling it a flapper on either, just sounds better than push the cone, lol.
Old 06-22-13, 09:36 PM
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Taking the cover off the CAS and holding the rotor in place did it! runs great now! thanks so much. No I've only got 3 problems. First is that after it gets warm if I'm curzin around and have to slow down (make a major turn, stop light, or what have you.) I push the clutch in and it idles really low about 500 rpms and acts like its almost gonna die. If i give it just a lil gas its fine. second is I believe some one has welded the read end I don't know what kinda idiot would do that but if I'm in gravel (I live out in the boondocks.) and go to turn even a little bit one tire will hang up and lock up periodically. third is that all the wires running to the heater control have been cut. so the heater doesn't come on. But there is a ton of hot air coming from under/sides of the steering wheel. Don't know whats up with that but it was about 70 today and i felt like i was in a oven. thanks for the helps guys means a lot.
Old 06-22-13, 09:46 PM
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Sounds like they removed the ducting under the steering wheel. If i recall, there should be a way to manually move the air mixture so it doesn't sit on heat, but i forgot where it is.

Have you removed the BAC or the dashpots on the throttle body? Those would be the place to start for your idle problem when coming to a stop.
Old 06-25-13, 07:22 PM
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So is it possible that I have a bad AFM? Drove the car for a few days everything was fine, now it is incredibly had to start cold. If I mess with the AFM Or unplug the AFM I can get it to start. once its warm I can plug it back in and it runs fine. if its warm it will start up no problem but if you let it sit for even a few min it will not start.
Old 06-25-13, 08:08 PM
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If you leave the car off for a few minutes after it has been running then the engine really isn't cold. So, are you having a problem on a true cold start or after the car has been sitting for a short period of time after it had been running?
Old 06-25-13, 08:16 PM
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after the car has been sitting even if its for 10 minutes or so it wont start with out help. but it you shut it off wait 30 seconds or so it will fire right up. also if you give it a shot of starting fluid it will start but you can't give it any gas or it will die. (just found that out) so its gotta be a no fuel issue I would assume.


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