NA8 Starting Issues

Engines, Transmissions & Final Drive questions and answers

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myredmx5
Fast Driver
Posts: 498
Joined: Fri Mar 02, 2012 5:13 pm
Vehicle: NA8
Location: Newcastle Area NSW

NA8 Starting Issues

Postby myredmx5 » Tue Oct 20, 2015 9:42 am

For a while now I have been trying to trace a problem with starting my NA8, which is very hard to start cold or hot.

I have been through every conceivable check I can think of and I have listed them below.

ECU = changed
Injector testing and cleaned = fine
Fuel filter = changed
Coil resistance = fine
Spark plugs = tested & changed
Spark plug leads = tested & changed
Cam position sensor = tested & changed
Mass air flow sensor = tested & changed
Throttle position sensor = tested & changed
Fuel pump relay = changed
Injector relay = changed
Clutch pedal switch = changed
Fuel pump = checked with leads in that black box and it runs and runs and runs.

The trick is that even though the the pump runs it does not mean it's pumping. I say that because when I changed the pump the car started instantly.

1green5
Driver
Posts: 31
Joined: Sun Aug 30, 2015 8:04 pm
Vehicle: NA6
Location: South Brisbane

Re: NA8 Starting Issues

Postby 1green5 » Tue Oct 20, 2015 10:06 am

- battery
- alernator
- starter motor
- compression check
- igniter

User avatar
StanTheMan
Forum legend
Posts: 6824
Joined: Thu Apr 24, 2003 11:00 am
Vehicle: NA6
Location: Balgowlah

Re: NA8 Starting Issues

Postby StanTheMan » Tue Oct 20, 2015 10:10 am

I had a pump with intermittent issues. Its been fine since I changed it. I also changed the relay which fixed the issue for a while.

But since you've changed a lot of it. Go for the least expensive options first....
Satans Ride called F33nix the resurrected NA6

93_Clubman
Speed Racer
Posts: 11854
Joined: Mon Aug 08, 2005 11:35 pm
Vehicle: Clubman
Location: Melbourne

Re: NA8 Starting Issues

Postby 93_Clubman » Tue Oct 20, 2015 1:44 pm

myredmx5 wrote:Fuel pump = checked with leads in that black box and it runs and runs and runs.
The trick is that even though the the pump runs it does not mean it's pumping. I say that because when I changed the pump the car started instantly.

From the above quote it sounds like you've fixed it by replacing the pump, unless it's playing-up again since swapping it over to another pump - or did you put the old pump back in because it seemed to be running ok outside of the tank?
Either way, it sounds like the so called 'blackwire' issue, ie the connectors inside the top of the fuel tank connector block & the fuel pump wires immediately leading from it have degraded so there's a poor electrical connection. If this is the case, & if the pump's ok, testing the pump anywhere other than out of its assembly will show it to be ok, because the issue is in the assembly connector & the wires plugged into it: viewtopic.php?f=55&t=46425

Btw, re igniter NA6 has a standalone igniter, but NA8 doesn't.

myredmx5
Fast Driver
Posts: 498
Joined: Fri Mar 02, 2012 5:13 pm
Vehicle: NA8
Location: Newcastle Area NSW

Re: NA8 Starting Issues

Postby myredmx5 » Tue Oct 20, 2015 8:54 pm

Your right 93_Clubman. I changed the fuel pump and all is fine. The old pump still turns out of the tank but I guess it doesn't actually move liquid. I will need to give it a test and see if it actually moves liquid.

The wiring is fine.

93_Clubman
Speed Racer
Posts: 11854
Joined: Mon Aug 08, 2005 11:35 pm
Vehicle: Clubman
Location: Melbourne

Re: NA8 Starting Issues

Postby 93_Clubman » Wed Oct 21, 2015 11:48 am

Perhaps this is where manga_blue's silting issue comes into play in terms of eventual affect on some fuel pumps (like yours) & wiring connectors (blackwire):
Image
viewtopic.php?f=55&t=46425&p=822568&hilit=fuel+pump#p822568


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