Editing Forums/Z31P/z31-performance-upgrade-forums engine-management/Z Start up

{{ForumImport
|op_user=Salster86
|op_date=2017-08-17 22:10:22
|post_count=8
|archive_url=/Z31performance_archive/forum/z31-performance-upgrade-forums/engine-management/536685-z-start-up.html
}}

'''Salster86:''' <small>(2017-08-17 22:10:22)</small>

K so as we all know, when you go to start your 86 Z you turn the key in the ignition switch to the ON position and immediately you hear a sound close to that of fuel injector prime up or a fuel pump that comes on… the sound then stops at which point you turn the key all the way and your Z fires up. Well, mine now makes the sound but it never stops and when I turn the key to start it won't. Any ideas?

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'''daniel_pearce:''' <small>(2017-08-18 03:20:31)</small>

ECU malfunction. Will probably need to be replaced.

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'''Salster86:''' <small>(2017-08-18 18:35:49)</small>

Well, it might also explain why the headlights pop up by themselves every so often. Hope the local dealer can get new ECU for a Z31… I'll have it checked out. Thank you, Sir.

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'''Salster86:''' <small>(2017-08-18 18:40:51)</small>

Been sort of hearing a little commentary in regards to Nissan and ECU issues , apparently it's not so rare.. any experience with this matter?

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'''daniel_pearce:''' <small>(2017-08-18 21:41:59)</small>

I had the exact same problem with an 85 Turbo about 5 years ago. Normally, you turn the key and you'll hear the buzzing noise for a few seconds. Eventually, it stops and you can start the car. I had the same continuous buzz and no start condition. It was a shame because I had the JWT POP (Performance Optimized Programming) upgrade.

The buzzing noise you're hearing may be from the E.F.I. Relay because of an ECM grounding issue. The buzzing is the effect from the failure of the ECM under load from heat. It's a common problem in these old Z31 ECU's as capacitors and micro-processors begin to fail from heat. Heat is the main enemy of electronic and engine components. Replace the ECU and you should be good to go. Sellers sell them on Ebay quite often. Ignore the ones that are selling them for over $250 a pop. Try to get one from a seller with a good reputation and make sure that the numbers on the ECU match the one for the year make and model of your car. The complete ECU list can be found here:

[http://z31.com/wiki/doku.php?id=resources:z31_ecu_list http://z31.com/wiki/doku.php?id=resources:z31_ecu_list]

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'''Salster86:''' <small>(2017-08-18 23:10:03)</small>

Righteous, thanks again!

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'''Salster86:''' <small>(2018-06-13 21:36:57)</small>

So to update, I purchased a replacement ECU online at www300zxpartsforyou.com. No change. So I accepted my lake of knowledge and had it towed to a repair shop. It ended up being a short in the fuse box wiring that prevented power to the injectors. Repair job set me back $350. She runs like a champ now.

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'''Salster86:''' <small>(2018-06-14 16:56:16)</small>

It was the small rectangular fusible link box right in front of the battery.