# 86.5 z24 engine electrical intermittent



## shohulski (Dec 29, 2013)

My 1986 1/2 King cab with z24 engine quits firing and tachometer drops to zero and restores.
Engine starts and runs fine for a bit and then acts like it turns off and then back on. At the same time the tach drops to zero and back. Feels like I turned off the battery. 
I had distributor, plugs and wires replaced and still happens. 
I have not pulled the passenger seat and looked at codes yet.
Is there some type of control circuitry that could cause this?


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## saudade (Apr 10, 2010)

Does it do this regularly, or intermittently? 
Does it seem to cut out at the same RPM? 
Does is do it in neutral or only driving in gear? 

You would need to determine if it's fuel or spark that quits.

There are many of us that experienced something similar. There are lot's of things that can cause it.

Getting any codes will help.


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## shohulski (Dec 29, 2013)

*D21 electrical*

Does it do this regularly, or intermittently?
-	Often but intermittently.
Does it seem to cut out at the same RPM? 
-	No
Does is do it in neutral or only driving in gear? 
-	Yes to both
You would need to determine if it's fuel or spark that quits.
I think it is spark. The problem began with an occasional not starting after running well for days. After sitting for a while (or days) it would start again. Changed fuel filter and checked pump ok.
Did it again.
A mechanic discovered the distributor was not sparking properly and changed it (as well as plugs and wire). Ran good for a few days and then noticed the Tach dropped to zero like it was un plugged and the engine quit and then resumed running just fine. After a few events like this the mechanic replaced the distributor again. Ran good for a couple days but started again but now more often. Driving a block it did it several times. Setting at idle it died the same way and would not start. I cranked it and got frustrated and dumped the clutch while cranking and it started. Still have the loss of electrical to Tach and engine dying but have not had the wont start problem. Guess I showed it;-)
There are many of us that experienced something similar. There are lot's of things that can cause it.
I hope to be one less who experiences it. I have too many tasks that need to be done and old Blue is blue cause he can’t help. 
Getting any codes will help.
My ECU is a MECS-G011 (2371007G00) and only has the on/off switch. When off both lights are on and when switch is on I get codes (I think).
I get a 23 and a 24 (red twice followed by green (3 or 4) and repeats.
From a list that I found that means Idle switch and throttle valve switch.


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## saudade (Apr 10, 2010)

The two codes are normal oddly enough. Move the shifter around will stop the 23. Press the gas pedal will stop the 24.

Sounds like you have a break in the harness somewhere. Not sure I can pin point if for you.

However, I had a problem with mine and turned out to be corroded splice connectors. Mine fed the injectors but there are others in there too. Check out:

http://www.nissanforums.com/hb-truck/160226-86-5-z24i-engine-cutout-solved.html


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## shohulski (Dec 29, 2013)

I saw that one but looks like a lot of work. Need to get up nerve and better weather to take it on.

In other posts there have been references to coil, blue relay and fusible link. Think they play here?


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## saudade (Apr 10, 2010)

I understand. I can't discount the other items until they're tested/inspected and ruled out.

I was out of options and ready to junk mine until someone suggested the splices.

Good luck!


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## shohulski (Dec 29, 2013)

Its all better now.
It got to the point where it would not start and I tried the timing light that proved no spark. Found a factory manual on line and tested voltage, ground and connections related to spark. 
Found that the power transistor (ignition control module) had 12 meg one way and 8 the other. Put in a new one and it started right up.

It cut off a couple of times after that so I replaced the ignition switch. It has run for several hours and still keeping fingers crossed. 

Learned a lot from this forum.
Thanks


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## shohulski (Dec 29, 2013)

Followup
I opened the ignition switch and found oxidation and arcing on coil (b/w) and ECCS (b/y) terminals. Less on other terminals.
At this age consider the cheap and easy fix or prophylactic action. Cheap $39 and easy (I did it myself).


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