NA6 not responding to Gnd/Ten and other issues

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Dweezle
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NA6 not responding to Gnd/Ten and other issues

Postby Dweezle » Thu Sep 20, 2012 5:17 pm

HI All,

Well i am having a few quite annoying issues.

I will try to list them as i believe they may all be related.
Hopefully someone has an idea on what could be going on.

First up, my car is a NA6 with a NA8 engine in it.


Issues
- Cold start, engine idles low (approx 650rpm), as it warms up idle rises until reaching about 1100rpm.
The idle screw is wound completely down. I can only make the idle higher.
Idle is not rock solid either.

- Using a timing light the slot on the pulley does not seem to move much, even without shorting our Ten/Gnd.
I have it set to 10 degrees.
On my previous 2 Na6's if you did not short Ten/Gnd then it would wave all about the place.
Shorting Ten/Gnd would make it quite set in its position. Mine currently sits quite solid without Ten/Gnd shorted.

- Shorting Ten/Gnd also does not seem to have an effect on idle speed either.

- The Check Engine light and Check Brakes light stay on always.
If i say, pull the handbrake on they get brighter but they are always on when ignition is on.

- Thermo fan does not seem to turn on.

- Car is running Pig rich. Approx 100ks half a tank.

I have just changed the ECU temp sensor on the back of the head, so the rich running may be cured?
I have not dríven it yet to test this.



Does anyone have any idea on what could be going on?

Many many Thanks in advance!!
ALL MUSCLE CARS ARE CRAP
Jeremy Clarkson

except of course, the Almighty VIPER!!!! 8)

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hks_kansei
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Re: NA6 not responding to Gnd/Ten and other issues

Postby hks_kansei » Thu Sep 20, 2012 5:40 pm

If the alternator is about to die it will light the charge warning light and the brake warning light together.
Is that what you're seeing? (I didn't think the NA had a check engine light?)


As for the GND/Ten not working it's possible that when it was swapped to a BP engine the diagnostic box wasn't hooked back up, or possibly it's not compatible with the new engine?

What ECU is it on? NA6 or NA8?
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

CHRISTolo
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Re: NA6 not responding to Gnd/Ten and other issues

Postby CHRISTolo » Thu Sep 20, 2012 5:43 pm

Had the same issue. I replaced the ISC valve.

Check the resistance. http://www.miata.net/garage/isc_files/image019.jpg

http://www.miata.net/garage/isc.html

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Dweezle
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Re: NA6 not responding to Gnd/Ten and other issues

Postby Dweezle » Thu Sep 20, 2012 6:13 pm

Gee Thanks Guys!!! :beer:

If the alternator is about to die it will light the charge warning light and the brake warning light together.
Is that what you're seeing? (I didn't think the NA had a check engine light?)


HKS, sorry i meant Charge and Brake light.
So it could be an alternator issue then?
I will have to lay a mutimeter over it tomorrow morning. I would love for it be that easy of an issue.


As for the GND/Ten not working it's possible that when it was swapped to a BP engine the diagnostic box wasn't hooked back up, or possibly it's not compatible with the new engine?
What ECU is it on? NA6 or NA8?


I thought that, but i get a TACHO signal to my mutimeter from IGN on the diagnostic box. Also i primed the fuel system after a filter change by shorting the fuel pump through the box. That all seemed to work.





Had the same issue. I replaced the ISC valve.


I have a spare intake manifold complete with Throttle body so it might be worth just swapping the throttle body and associated bits over?

Cheers all!!

Was stressing me out a bit.
I feel calmer now i have things to check!! :D
ALL MUSCLE CARS ARE CRAP
Jeremy Clarkson

except of course, the Almighty VIPER!!!! 8)

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hks_kansei
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Re: NA6 not responding to Gnd/Ten and other issues

Postby hks_kansei » Thu Sep 20, 2012 6:23 pm

If it's charge and brake I would certainly say the alternator's on the way out. (I doubt it's the cause of the other issue though)
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

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Dweezle
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Re: NA6 not responding to Gnd/Ten and other issues

Postby Dweezle » Thu Sep 20, 2012 6:25 pm

Thankyou HKS, I actually have a spare alternator floating about.
Might be worth just throwing that on and seeing if it helps.
ALL MUSCLE CARS ARE CRAP
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except of course, the Almighty VIPER!!!! 8)

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hks_kansei
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Re: NA6 not responding to Gnd/Ten and other issues

Postby hks_kansei » Thu Sep 20, 2012 6:31 pm

No harm in trying.

except for the extreme rage and hatred that bubbles up when you try to get the alternator belt back on. (why didn't mazda just give the tensioner another 10mm of adjustment? that would have made it so much easier than having to stretch and strain to get the bloody belt over the lip on the pulley)
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

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Jeo
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Re: NA6 not responding to Gnd/Ten and other issues

Postby Jeo » Thu Sep 20, 2012 8:40 pm

I had the NA6 ECU running my NA8 when I first got it. It too ran pig rich.

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Re: NA6 not responding to Gnd/Ten and other issues

Postby emily_mx5 » Thu Sep 20, 2012 11:50 pm

solomiata wrote:When retaining the 1.6 TB for the swap the thermal AIC valve that is on the 1.6 manifold has to be eliminated since there is no provisions for it on the 1.8 manifold (the thermal AIC valve shuts off the air to the AIC when the engine reached operating temperature). Some have installed a selenoid as a replacement. What I did was to install a restrictor in the AIC air intake hose, about 3/32" and re-adjust the air bypass screw in the TB. This allows enough air in during cold start to allow the engine to idle until warm but not enough to cause a super high idle. It is a compromise, the cold idle will be a little low and the hot idle will be a little high (about 1000 rpm).

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Dweezle
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Re: NA6 not responding to Gnd/Ten and other issues

Postby Dweezle » Fri Sep 21, 2012 8:07 am

Thanks Em :NETPOINTZ: :NETPOINTZ:

You know i have read that page a million times in the past but completely forgot it existed for my own issues!!
UGHH!!

Could explain why i was having difficulty seeing the ISCV. :oops:

Seeing how i have a spare one I might look into getting it to fit.
I would like the car to behave normally before whacking the MS on.
ALL MUSCLE CARS ARE CRAP
Jeremy Clarkson

except of course, the Almighty VIPER!!!! 8)

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Dweezle
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Re: NA6 not responding to Gnd/Ten and other issues

Postby Dweezle » Fri Sep 21, 2012 10:31 am

Okay..

Ran down to the garage and did a few tests for the Fan Issue.

If i short the connector on top of the thermostat housing with the ignition on i just get a audible click from the relay box i believe.
If i short TFA/GND in the diagnostic box i get the same "click".

The fan does not turn on in both cases.
Would i be correct in assuming as i get a "click" that the relay is fine and that it could be the fan motor?
Can anybody help in suggesting which fuse it would be?



In other news, i believe i am still running a ISCV.
Image

Image

That is the ISCV in the pictures right?
if so i will test the resistance of that today too.


Thanks again to everyone for your help.
ALL MUSCLE CARS ARE CRAP
Jeremy Clarkson

except of course, the Almighty VIPER!!!! 8)

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Re: NA6 not responding to Gnd/Ten and other issues

Postby jorgan92 » Fri Sep 21, 2012 10:39 am

Short fan pins, hear click, check fan for voltage? Would be the easiest way to determine if the relay is buggered or the fan.

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Dweezle
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Re: NA6 not responding to Gnd/Ten and other issues

Postby Dweezle » Fri Sep 21, 2012 12:49 pm

Thanks Jorgan!

Did just that.
Turns out i am getting 12v at the connector of the fan but the fan is not budging.
So i assume the fan/motor is dead?



Sent from my GT-I9100T using Tapatalk 2
ALL MUSCLE CARS ARE CRAP
Jeremy Clarkson

except of course, the Almighty VIPER!!!! 8)

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Re: NA6 not responding to Gnd/Ten and other issues

Postby jorgan92 » Fri Sep 21, 2012 1:12 pm

Sounds about right.

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Dweezle
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Re: NA6 not responding to Gnd/Ten and other issues

Postby Dweezle » Sat Sep 22, 2012 9:48 pm

Solved part of an issue.

After a few tests, i figures it was the passenger side fan/motor that was not turning on.
I was getting 12V to the connector. but the fan was not budging.

I am not on the lookout for a replacement fan and motor.
But to make it all work for now i decided to wire up the A/C fan to the Thermo Sensor instead.

The A/C fan uses a different connector.
So i just made a temp bypass using connectors from Jaycar that just fit to the pins.
Cost me $6.

I will tidy it all up before driving.
This was just to test if it would work.

Image

I have not tested this with the car making it turn on, but if i short out TFN/Gnd or just the connector on the thermosensor the fan now turns on.
Just means i am using the A/C fan not the passenger side fan.
Should work well.

I must add that i wired it wrong to start with.
Noticed it was blowing air out the front.. WHOOPS.
Fixed that by just swapping the connectors.


I also bought a new thermosensor from my brother at Repco.
Image




So anyone with a radiator fan and motor passenger side they need gone?? :D
ALL MUSCLE CARS ARE CRAP
Jeremy Clarkson

except of course, the Almighty VIPER!!!! 8)


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