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Old 04-07-2011, 09:18 AM   #1
Kevyn
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Default 87 GXL wont start

Hi I have a 87 gxl that I bought from a kid that had it sitting for 7 YEARS.
i changed the oil, did a whole tuneup and put a new fuel pump and tank in(the old tank was rusted because the kid left the gas cap off whille it was sitting, water got in the , ect.)
So after alot of work i got it to turn on for 10-15 seconds but as soon as i touched the accelerator it died and now I cant get it to turn back on.
I think it keeps flooding because i always have to pull the spark plugs out to clean them.
it builds up good oil preassure when i am cranking continously
i am getting spark but it feels weak (i got shocked by putting my hand on there and it really wasnt anything haha)
Ive tested the restance on the coils: .8 ohms
also I think a pretty decent sized exhaust leak.
Any help is appreciated, thanks







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Old 04-07-2011, 10:00 AM   #2
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take some ATX fluid and put it on all 3 faces of both rotors and let it sit. Sounds like bad compression, this should help to boost that compression and help loosen the seals at the same time.
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Old 04-07-2011, 11:17 AM   #3
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how would i get it on all three faces?

nvm that was a dumb question.
So I just let it sit for a couple days? hours?
also how much atx fluid?

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Old 04-07-2011, 11:23 AM   #4
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not a ton, but enough to wet the apex seals. And letting it sit for 30 minutes or so should allow it to free some things up.
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Old 04-07-2011, 11:25 AM   #5
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Quote:
Originally Posted by Kevyn View Post
Hi I have a 87 gxl that I bought from a kid that had it sitting for 7 YEARS.
i changed the oil, did a whole tuneup and put a new fuel pump and tank in(the old tank was rusted because the kid left the gas cap off whille it was sitting, water got in the , ect.)
So after alot of work i got it to turn on for 10-15 seconds but as soon as i touched the accelerator it died and now I cant get it to turn back on.
I think it keeps flooding because i always have to pull the spark plugs out to clean them.
I have good compression
it builds up good oil preassure when i am cranking continously
i am getting spark but it feels weak (i got shocked by putting my hand on there and it really wasnt anything haha)
Ive tested the restance on the coils: .8 ohms
also I think a pretty decent sized exhaust leak.
Any help is appreciated, thanks
Quote:
Originally Posted by tweiss3 View Post
take some ATX fluid and put it on all 3 faces of both rotors and let it sit. Sounds like bad compression, this should help to boost that compression and help loosen the seals at the same time.
Quote:
Originally Posted by Kevyn View Post
how would i get it on all three faces?

nvm that was a dumb question.
So I just let it sit for a couple days? hours?
also how much atx fluid?
Do you have any compression numbers or is it just assumed. You can have a lot of different issues. Anything and everything from a vacuum leak to poor compression, or a leaking/clogged injectors. When you did your tune up did you happen to swap out the fuel filter? If you didn't, I would hazard a guess that you have clogged fuel injectors.
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Old 04-07-2011, 12:17 PM   #6
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a friend of mine told me to change the fuel filter AFTER i got it to run once.
I guess that was a mistake.
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Old 04-07-2011, 01:14 PM   #7
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Truth of the matter is if the car has been sitting for 7 years it's going to need a lot of work. I would suggest pulling the injectors, sending them out to be cleaned and flow tested. I would then pull all the filters (that includes the fuel and oil--unless you recently did them). Replace plugs, test coils as per FSM (Factory Service Manual) instruction, and test plug wires to ensure they're still good. Additionally I would double check fuel pressure and inspect the Fuel Pressure Damper (FPD).

I would also look at getting compression numbers from the rotors so you know what you have.
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Old 04-07-2011, 02:14 PM   #8
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^ Agree with Vex on all of the above. In addition, I recommend flushing the cooling system and putting in fresh coolant. Also, since many of the rubber hoses and belts are likely dry rotting, you'll probably want to replace those as well.
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Old 04-08-2011, 08:30 AM   #9
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Quote:
Originally Posted by vex View Post
Truth of the matter is if the car has been sitting for 7 years it's going to need a lot of work. I would suggest pulling the injectors, sending them out to be cleaned and flow tested. I would then pull all the filters (that includes the fuel and oil--unless you recently did them). Replace plugs, test coils as per FSM (Factory Service Manual) instruction, and test plug wires to ensure they're still good. Additionally I would double check fuel pressure and inspect the Fuel Pressure Damper (FPD).

I would also look at getting compression numbers from the rotors so you know what you have.
ive replaced all filters, plugs, wires. I m the process of flushing the coolant, replacing all other fluid, and getting new hoses and belts. I guess in the mean time i should check compression.
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Old 04-08-2011, 08:34 AM   #10
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also would it be a good idea to just buy some used injectors from somebody instead of getting mine cleaned, flow tested, ect?
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Old 04-08-2011, 10:05 AM   #11
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Quote:
Originally Posted by Kevyn View Post
also would it be a good idea to just buy some used injectors from somebody instead of getting mine cleaned, flow tested, ect?
Nope, it only costs about $20~$25 per injector to get them cleaned & flow tested. A reputable shop will provide documentation of before/after results, and will also replace the replacable wear & tear parts (i.e., pintle caps, O-rings, grommets, etc.) for that price. Which makes them as good as new. With used injectors, you're basically replacing your old injectors with another set of injectors of unknown health.
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Old 04-08-2011, 11:43 AM   #12
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Quote:
Originally Posted by Kevyn View Post
ive replaced all filters, plugs, wires. I m the process of flushing the coolant, replacing all other fluid, and getting new hoses and belts. I guess in the mean time i should check compression.
Because you replace wires does not guarantee that they are without defect. You'll need to check the Resistance of each line to ensure that there is no break in the wire or tear in the insulation. Once that's done you'll need to verify the coils are functioning properly and delivering the proper voltage to the plugs as per FSM instructions.

Compression numbers are good to have, but require good battery voltage and cranking RPM. It's good to know that all 3-faces are holding compression as well as the total amount of compression they can provide. Or if you have the money you can purchase a rotary compression tester from one of the vendors on this site which will provide a much better analysis of the condition of the engine. I plan on purchasing one in the future, as I'm poor right now.
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Old 04-08-2011, 12:09 PM   #13
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Lacking a compression tester (rotary specific or otherwise), you can do a quick "poor man's compression test" to get a quick thumbs up/down assessment of your rotary engine's compression. Here's the gist of it:

1. Remove the EGI fuse, and disconnect the CAS (Crank Angle Sensor) - this kills spark & fuel, preventing the car from firing while testing. The EGI fuse is located in the fuse box under the hood, driver's side strut tower.

2. Make sure your battery is fully charged, and/or have another car handy to hook jumper cables to your battery. You'll be cranking your engine repeatedly and won't want to drain your battery down.

3. Remove the trailing (top) spark plug from one of the rotors, doesn't matter which one you do choose to do first.

4. Get yourself in earshot of the spark plug hole - don't need to be TOO close, leaning over the fender will work, and have an assistant floor the throttle open while cranking the engine.

5. While it's cranking, listen to the sounds made -- you should hear a consistently strong & rythmic POP--POP--POP sound coming from the open spark plug hole, meaning you've got compression on all 3 faces of that rotor. If the loudness of the POPs are weak, or more importantly, if the rythm is broken up, i.e., POP--POP--(silence)--POP, then you've got internal problems with that rotor that most likely will require a tear down/rebuild.

6. Repeat steps #3-5 for the remaining rotor, after replacing the spark plug in the one you just did.
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Old 04-08-2011, 12:46 PM   #14
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You don't need to disconnect the CAS. The coils are fed power by the EGI INJ fuse, so they (coils and injectors) can't fire if you pull that fuse. IF you pull the EGI COMP instead....same deal, the computer controls firing of the coils so they can't fire if that fuse is pulled. Either of the EGI fuses kills fuel and coils firing.
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Old 04-08-2011, 01:21 PM   #15
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Quote:
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You don't need to disconnect the CAS. The coils are fed power by the EGI INJ fuse, so they (coils and injectors) can't fire if you pull that fuse. IF you pull the EGI COMP instead....same deal, the computer controls firing of the coils so they can't fire if that fuse is pulled. Either of the EGI fuses kills fuel and coils firing.
Fred - Good point, pulling the EGI fuse does in fact kill both fuel & spark, so there is no need to disconnect the CAS that I can see. Oddly enough, the compression test procedure in my '89 FSM(ref. page C-7) states to disconnect the CAS, but it is completely silent with regards to pulling the EGI fuse - go figure!
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