Patchy's Fawlty Towers risk management. Enter at own risk

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hks_kansei
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Re: Patchy's Fawlty Towers risk management. Enter at own risk

Postby hks_kansei » Sat Nov 12, 2016 4:29 pm

StanTheMan wrote:Ok cheers I'll check that.
Not sure how to test relays. Might have to call a friend.


When they're out of the car they'll usually have 4 pins.

Two are for the low current, from the ecu or whatever.
The other two are for the high current, the thing they're switching on and off.


You should be able to test them easily on the bench with a spare battery.
Wire the ground pins to the neg terminal.
Wire the high current positive to a spare light bulb, or multimeter (something that can let you know power gets there, the bulb will light up)
Then put power to the low current, when you do the light you wired in should turn on, when you remove the low current wire it should go off.

http://www.12voltplanet.co.uk/user/Driv ... iagram.png

There's a diagram of a basic relay.
Most have the same numbers written on them as in the diagram..... But the na seems to often use weird proprietary relays I've noticed.
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Re: Patchy's Fawlty Towers risk management. Enter at own risk

Postby StanTheMan » Sun Nov 13, 2016 9:35 am

No spark no fuel as far as I can see
Cam timing correct.

But when the ignition gets turned on the temperature gauge goes straight to hot. Huh?

The plug that goes on the rear temp guage sensor is on, but I can't really see. With my injured hand I can't get it off haven't got enough strength. Nor enough room.

Before I do anything else cause that can't be good. What should I be looking at?

I'll need to check if I've blown any fuses below the dash
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Re: Patchy's Fawlty Towers risk management. Enter at own risk

Postby StanTheMan » Sun Nov 13, 2016 10:28 am

Sorry can confirm spark.
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Re: Patchy's Fawlty Towers risk management. Enter at own risk

Postby StanTheMan » Sun Nov 13, 2016 10:30 am

May also have to check the fuel filter I changed over a few weeks ago.
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Re: Patchy's Fawlty Towers risk management. Enter at own risk

Postby 93_Clubman » Sun Nov 13, 2016 10:55 am

StanTheMan wrote:But when the ignition gets turned on the temperature gauge goes straight to hot. Huh? The plug that goes on the rear temp guage sensor is on, but I can't really see.

On the standard NA6, the temp gauge gets its reading from one of the two CTS at the rear of the head. The other (usually green topped) CTS at rear of the head goes to the ECU. Perhaps these are reversed. CTS on top of the thermostat is for the fans.
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Re: Patchy's Fawlty Towers risk management. Enter at own risk

Postby StanTheMan » Sun Nov 13, 2016 11:36 am

The green one was never taken off the whole hose & cover was taken off as one.
The little black one for the gauge just goes on right? It's defenately on
The water hasn't reached the back ye. Will that make s difference?
Just before I took the head off one of the water hoses burst. Got hot Drove it home & parked it. Next weekend I took it apart.

The relay under the dash for fuelpump does nothing , no click when ignition turns on. Although unrelated to the gauge issue. I'll get it tested by a sparky friend

Can't tell if the fuel injectors are working or not. However the relay in the engine bay doe click when switched on.
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Re: Patchy's Fawlty Towers risk management. Enter at own risk

Postby hks_kansei » Sun Nov 13, 2016 12:01 pm

Ah, if the coolant hasn't reached the sensor yet it won't read properly.

They can only read temps when wet, when in air they usually just send out a signal at the max of their reading (can't remember if max cold, or max hot)
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Re: Patchy's Fawlty Towers risk management. Enter at own risk

Postby 93_Clubman » Sun Nov 13, 2016 2:16 pm

Yeah, under dash fuel pump relay is silent - if you have a multimeter or test light just check for power at the end of the wiring loom where it plugs into the top of the fuel tank. While you're there you can then test for continuity at the connector on top of the fuel tank. This will then rule in or out those two possibilities.
Re fuel injection relay, good that you hear it operate, but best to take it apart to check internals or replace it. Alternatively, you can bypass it with some wire (like coat hanger) for testing purposes or in an emergency. Caffeine has posted on later, while manga_blue has posted on former & possibly latter.

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Re: Patchy's Fawlty Towers risk management. Enter at own risk

Postby 93_Clubman » Sun Nov 13, 2016 2:28 pm

93_Clubman wrote:While 'Fuel Inj' relay is labelled such it also affects spark. However, manga_blue & caffeine have used a temporary work around for it (piece of coat hanger wire), which might allow your car to start - just have to find the thread - here you go:
viewtopic.php?f=29&t=38526&p=535770&hilit=relay#p535770
viewtopic.php?f=29&t=49188&p=617511&hilit=relay#p617511

93_Clubman wrote:Here's main relay pinout pic to go with the above link:
viewtopic.php?f=29&t=38526&p=535770&hilit=relay#p535770
MAIN Relay pinouts.jpg

MAIN Relay pinouts.jpg
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Re: Patchy's Fawlty Towers risk management. Enter at own risk

Postby StanTheMan » Sun Nov 13, 2016 3:31 pm

Ok tried that.
Used a stainless steel jumper.
Still no luck that would mean it's potentially the relay under the dash?

The contacts of the plug are blackish so that needs looking at first.
Last edited by StanTheMan on Sun Nov 13, 2016 3:36 pm, edited 1 time in total.
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Re: Patchy's Fawlty Towers risk management. Enter at own risk

Postby 93_Clubman » Sun Nov 13, 2016 3:36 pm

Yeah, it could be under dash relay or the top of tank connector preventing power to fuel pump. Also, as you mentioned earlier there could be a fuel filter issue.

Reposted to include full links:
93_Clubman wrote:
93_Clubman wrote:While 'Fuel Inj' relay is labelled such it also affects spark. However, manga_blue & caffeine have used a temporary work around for it (piece of coat hanger wire), which might allow your car to start - just have to find the thread - here you go:
viewtopic.php?f=29&t=38526&p=535770&hilit=relay#p535770
viewtopic.php?f=29&t=49188&p=617511&hilit=relay#p617511

93_Clubman wrote:Here's main relay pinout pic to go with the above link:
viewtopic.php?f=29&t=38526&p=535770&hilit=relay#p535770
MAIN Relay pinouts.jpg

MAIN Relay pinouts.jpg

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Re: Patchy's Fawlty Towers risk management. Enter at own risk

Postby StanTheMan » Sun Nov 13, 2016 3:42 pm

Fuel pump works when isolated through the diagnostics box
GRD to F/P it bypasses both relays as far as I know

When switching on ignition without any jumping there is no sign of fuel pump.
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Re: Patchy's Fawlty Towers risk management. Enter at own risk

Postby manga_blue » Sun Nov 13, 2016 3:46 pm

I've refined this universal diagnosis system for when the thing won't start after a rebuild:

1. You've forgotten to do something or else you've done something wrong.
2. Go and have a surf or a walk or a paddle or something else that's active, not in the garage and totally unrelated
3. Come home and drink beer until you've had enough beer
4. Go to bed and sleep on it until the next morning or maybe a morning or two later...
5. ... when eventually what you did wrong dawns on you.
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Re: Patchy's Fawlty Towers risk management. Enter at own risk

Postby StanTheMan » Sun Nov 13, 2016 3:48 pm

Your brilliant Phil

That's pure gold. A beer would be good in this heat. Although currently there wouldn't be enough beers in Seaforth
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Re: Patchy's Fawlty Towers risk management. Enter at own risk

Postby 93_Clubman » Sun Nov 13, 2016 3:56 pm

StanTheMan wrote:Fuel pump works when isolated through the diagnostics box GRD to F/P it bypasses both relays as far as I know
When switching on ignition without any jumping there is no sign of fuel pump.

When you say the 'fuel pump works', what indicator do you have of that?
Normally when switching on the ignition you won't hear the fuel pump, you'll only hear the fuel injection relay, as the fuel is pumped only upon cranking.


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