2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

another electrical problem HELP!!!

Old Aug 22, 2012 | 10:35 PM
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Exclamation another electrical problem HELP!!!

hi everyone my car took a **** again today. right before it died it started to misfire like crazy and some crazy hesitation. some of my electrical stuff stayed on even with the key off. i dont think im getting any spark also. rpm needle wont even flinch when trying to start the car. so here it is. i think its my front harness or that harness that plugs into the coils that has a short!! what do you guys think?! ooh

car details:
86 rx7 n/a
138,000 miles
new plugs and oil
new alt and optima battery full charge yellow top

ps. positive battery terminal was crazy hot when i took it off and burnt my fingers
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Old Aug 22, 2012 | 10:47 PM
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Which electrical stayed on w/the key to off? Was the battery cable hot before starting the car or after?

Last edited by satch; Aug 22, 2012 at 10:50 PM.
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Old Aug 22, 2012 | 11:26 PM
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Originally Posted by satch
Which electrical stayed on w/the key to off? Was the battery cable hot before starting the car or after?
the battery cable was blazing hot after trying to start the car. it was craking but no fire.. and it was in the off position and the e-fan i have stayed on
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Old Aug 22, 2012 | 11:34 PM
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One thing you might have is a poor ground as it relates to the starter. If the battery terminal was hot before starting the car then that might point to something else. So check your connections at the starter as it relates to the battery (you have two them, both rather thick cables).
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Old Aug 22, 2012 | 11:46 PM
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Originally Posted by satch
One thing you might have is a poor ground as it relates to the starter. If the battery terminal was hot before starting the car then that might point to something else. So check your connections at the starter as it relates to the battery (you have two them, both rather thick cables).
But my starter still cranks strong. I just don't get spark. Nor does it start. I'm getting sad fml
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Old Aug 22, 2012 | 11:51 PM
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You have high resistance at the positive battery terminal but you didn't notice it being hot before trying to start the car so you need to address the starter as it relates to the situation. You can also disconnect the 4 wire plug to the Main Relay and turn the car over and see if the same problem persists. W/the relay disconnected the wires that power the injectors,coils, ECU etc will not have power so this would help to eliminate some things. You could also place the Red meter lead on the positive battery post and the Black meter lead on the positive cable and look for voltage drops. The cable needs to be connected to the battery terminal and you would want to do this test w/the lights on or trying to start the car. The voltage drop registered should be very low.

Last edited by satch; Aug 22, 2012 at 11:55 PM.
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Old Aug 23, 2012 | 09:35 PM
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Originally Posted by satch
You have high resistance at the positive battery terminal but you didn't notice it being hot before trying to start the car so you need to address the starter as it relates to the situation. You can also disconnect the 4 wire plug to the Main Relay and turn the car over and see if the same problem persists. W/the relay disconnected the wires that power the injectors,coils, ECU etc will not have power so this would help to eliminate some things. You could also place the Red meter lead on the positive battery post and the Black meter lead on the positive cable and look for voltage drops. The cable needs to be connected to the battery terminal and you would want to do this test w/the lights on or trying to start the car. The voltage drop registered should be very low.
can this cause all the problems?

it was touching the body when i found it but it was twisted together with the other end. i dont even know what this wire does
Attached Thumbnails another electrical problem HELP!!!-img_2045.jpg  
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Old Aug 24, 2012 | 08:14 AM
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That is a voltage wire and if it were grounding out then that is not good. Did you do the voltage drop test yet? There are many possible causes for your problem so diagnosing the problem is a good course of action. The voltage drop test should tell you whether the battery clamp/cable is in good condition or not. Doing the test should indicate very, very little voltage.
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Old Aug 24, 2012 | 03:14 PM
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From: los angeles
Originally Posted by satch
That is a voltage wire and if it were grounding out then that is not good. Did you do the voltage drop test yet? There are many possible causes for your problem so diagnosing the problem is a good course of action. The voltage drop test should tell you whether the battery clamp/cable is in good condition or not. Doing the test should indicate very, very little voltage.
The battery clamp is good cuz its new. Well I fixed that wire and it's the same ****. No ignition. I can hear my fuel pump so it works. And my car cranks.*
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Old Aug 24, 2012 | 04:10 PM
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that is the alternator and main chassis harness main +12v feed goes through the 80 amp main fuse on your s4. Check under the dash and see if you have any burnt fuses, and check the fuse box under the hood. If that wire shorted out and hit the chassis the 80 amp main fuse is the first thing to blow ...if it blows you wont be able to crank the car...so doesnt sound like its blown...im guessing if your wiring is twist tied together like that and obviously ghetto rigged you will need to check your wiring...simply remove more of the chassis harness sheathing that is near suspect ghetto rigged area and keep searching sounds like a loose wire
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Old Aug 24, 2012 | 04:41 PM
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From: tulsa,ok.
Have you checked both EGI fuses?
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Old Aug 29, 2012 | 02:50 PM
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Originally Posted by satch
Have you checked both EGI fuses?
both egi fuses are good they are new
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Old Aug 29, 2012 | 03:04 PM
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so happed to start the car this morning and it took a bit to fire but it started ran for 15 sec with my foot on the throttle at 3k and BAM!! it dies and falls flat on its face.
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Old Aug 29, 2012 | 05:07 PM
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sounds like the wiring from your eccentric shaft position sensor is messed up ....it sends tach signal and spark timing from there ...
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Old Aug 29, 2012 | 10:33 PM
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Originally Posted by gdnimr0d
sounds like the wiring from your eccentric shaft position sensor is messed up ....it sends tach signal and spark timing from there ...
Where do I find that?! Any pictures you can help me with?
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Old Sep 1, 2012 | 09:45 AM
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From: New Hampsha
Originally Posted by linuslove
Can anyone help me to where to go on this huge complex site to get input on a problem involving my Mazda RX7 GXL 1990?
how many ****** threads are you gonna post this in... gtfo
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