Electrical Issues
 

I have a 1991 RX-7, that has some electrical problems. It will drain the battery in 3 days. I had someone look at it, and he seemed to find the problem, and all was ok for the summer 2 years ago. I then had them do a little more work on the car, and his monkey of a mechanic screwed something up to where it now drains the battery again.

I am in the New England area (Southern NH) and would love some recommendations on someone who is a very knowledgable RX-7 mechanic. I would be interested in someone in the NH, MA, ME, VT or CT areas.

Any help would be appreciated.

Thanks,
Mark

You might want to try the Engine Management Forum on here, if you get no answers.
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Coupe or vert ? i had an 88 vert that would drain the battery in a couple of days and i could never figure it out until one day i noticed light leaking out of the trunk ..... the trunk light was on with the trunk closed and was killing the battery

It's a coupe...I thought I found it once, with the glove box door, but turned out not to be. We know it's one of the over engineered modules.

Thank you...I will do that.

Electrical problems can be annoying but there is a great way to test for parasitic draw. All you need is a multi-meter.

Set it to 200mA or something. Take your negative terminal off. Now take your meter and complete the circuit by connecting one probe to Neg post and the other to the cable you just took off the post. Its nice to do this with alligator clips. If you get a negative reading it doesnt matter, that just means you have leads backwards. The number is what matters.

Now one by one, in a logical order, remove fuses while checking meter for a current drop. If it doesn't drop re-install the fuse. Start first with the ones under the hood(PAL fuses). Wait for your reading to drop. When it drops you know you found the affected circuit.

Under 50mA is considered normal. My rx has a parasitic draw of 31mA. Anything above 50mA is considered parasitic and will kill the battery over time.

**You MUST do this test with all accessories off, doors closed, key out***(just having the key in raises draw by about 10mA), all lights off. Everything must be off.**

With some patience you will narrow the search down to the affected circuit. Hope this helps.
I'll add that this could get hairy and schematics might be required. If so, when examining the affected circuit diagram look for common points.

In addition to what Rotary Alkymist suggested, you can have excessive parasitic draw due to poor grounds too. For example, things like the dome light may be drawing power but appears as being off due to voltage drop in its ground. See more here: Proper RX-7 Grounding Procedures