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?????(Bad grounds = no spark)?????

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Old 02-04-08, 03:01 PM
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Exclamation ?????(Bad grounds = no spark)?????

wow this is'nt common, my car wont start.... i think its a grounding issue because i checked for spark (test = no spark) so i have a couple of quick questions...

1. If i just painted my engine/engine bay would the paint stop my engine from
grounding correctly?

2. Where are all of the grounds located/where should they attach?

Thanks,
Sean
Old 02-04-08, 04:19 PM
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yes paint can block from grounding properly. Find aaron cake's site and look up the grounding write up. As far as grounds that attach to the firewall, there is one from tranny to firewall and then a ground for the battery on the drivers shock tower (this is the one i would be concerned with). Are you sure that battery is fully charged?
Old 02-04-08, 04:47 PM
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How do i switch the battery terminal connectors to new ones? The ones i have are fucked. how long are they and how do/where do they connect? the battery is new but ill give it a charge. where is that ground for the battery??? do you have a pic?
Old 02-05-08, 09:11 AM
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http://www.aaroncake.net/rx-7/grounding.htm will answer many of your questions.
Old 02-05-08, 01:20 PM
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The ground for the ignitors in the coil assy get grounded thru the attach points of the coil/ignitor assy. Talking about the four studs that hold then on the chassis. If you unbolt a coil/ignitor assy and put it on top of a rag/piece of wood etc, it won't work. It gets grounded from being mounted to the chassis, nowhere else.

Either that or you blew your ENGINE fuse.
Old 02-05-08, 07:44 PM
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So close yet so far!!!

ok so ive checked a bunch of things trying to get this car running

1. Crank Sensor = Good!
2. Compression = Good?
3. new leading spark plugs (they didnt have trailling in stock but the ones in are still in good condish)
4. solenoids setup correctly
5. getting fuel when i try to start it
6. the car has all new hoses and almost all new sensors
7. BACV clicks when setup to the batery but reads 13.8 ohms (sposed to be within 10 and 12.2)
8. brand new battery and alternator.

it still wont start so does anyone have any ideas on what i should check next? what is the problem?
Old 02-05-08, 08:21 PM
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Got spark?

By the way, your the same guy with no 12v at the pin 3B on the ECU. Right? No batt voltage at 3B duing a Cold start makes the mixture too lean because the afm is being used for fuel delivery instead of the preset Start map inside the ECU. Make sense?

Have you tried a one to two second blast of starter fluid in the airfilter yet. No more than that is needed.
Old 02-06-08, 12:45 AM
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Threads merged... only start one thread per subject per member.
Old 02-06-08, 05:31 AM
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sorry icemark!!! thanks for the merg

fuse is fine. coils will just stop working if just set on a block of wood, for example if i had taken them out and set them on the work bench and tried to put them in they wont work?

that sounds like im stupid for even asking if thats what you mean : )
Old 02-06-08, 08:30 AM
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Originally Posted by GOT-RTRY
sorry icemark!!! thanks for the merg

fuse is fine. coils will just stop working if just set on a block of wood, for example if i had taken them out and set them on the work bench and tried to put them in they wont work?

that sounds like im stupid for even asking if thats what you mean : )
No. The gnd circuit for the ignitors is thru the base of the coil assy to the chassis. If the coil isn't bolted to the chassis there is no path for the gnd to go to.

I'm saying that if you had a good working coil assy, and had the engine running, if you unbolted that coil assy and lifted up on it and put it on a rag or piece of wood etc, then the coil would stop working.

Or put another way, if you painted the surfaces where the coil assy rests on the chassis, there wouldn't be a path for the gnd signal, much like putting the coil assy on a rag etc. Not saying that is your problem but has potential for being your problem.

You won't get spark if you failed to attach the ECU grounds to the top of the engine on the rear rotor assy upon reassy of the engine. If you have not had the harness off the engine, then forget this idea.

You've been probing the ECU outputs/inputs. Go to pin 2A with the key On and see if you have 5vdc on that wire with the plug on the ECU.

Last edited by HAILERS; 02-06-08 at 08:38 AM.
Old 02-06-08, 04:52 PM
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ok now i understand. i think what im going to do is scrape the paint off underneath all of the grounds and make sure there set up correctly and add some, for example the ground from the battery to the lead coil. i will check the 2a coil packs when i get home tonight, and i took the coils apart for cleaning a while ago does anyone know/can give me a link on how it is put together, for example the wires under the plastic covers, so i can check for errors,

Thanks,
Sean

P.S. What is an Earthwire Kit? does it help replace the stock grounds or is it just a kit to add more?

Last edited by GOT-RTRY; 02-06-08 at 05:03 PM.
Old 02-07-08, 04:28 PM
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(L&T Coils = Bad) Haynes manual says they should read 0.2 to 1.0 ohms, the ones i have read from 18.0-22.0 so i have to replace them right??? and can i replace them with ones from an N/A?
Old 02-07-08, 06:43 PM
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kinda need info soon... will try to find in archive.
Old 02-07-08, 10:41 PM
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Originally Posted by GOT-RTRY
(L&T Coils = Bad) Haynes manual says they should read 0.2 to 1.0 ohms, the ones i have read from 18.0-22.0 so i have to replace them right??? and can i replace them with ones from an N/A?
the Turbo uses the same coils as the non turbo
Old 02-08-08, 01:53 PM
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thanks
Old 02-08-08, 06:22 PM
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You wouldn't have a spare cas laying about, would you?
Old 02-09-08, 10:09 AM
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no unfortunatly i dont
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