A wee problem or two. Think they might be related?

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Steampunk
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Re: A wee problem or two. Think they might be related?

Postby Steampunk » Sun Dec 09, 2012 1:05 pm

The problem really is the actual model of the car. I also would loath selling it, it's the old heart vs head debate.
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eDrive.ie

Re: A wee problem or two. Think they might be related?

Postby eDrive.ie » Tue Dec 11, 2012 5:11 am

Thanks guys. I have the car totally dry now. I never took out the carpet, but lifted most of it. I might end up taking it out in the end though. It could do with a power-clean or replacing. The ECU looks okay and I used electrical contact spray and a toothbrush on all the connections that had corrosion. They came up pretty well. I've soaked every wire and fuse I can see with WD40 too. I totally understand the wicker effect of water on all surfaces. Also, when you have water in a vessel, it'll travel around in vapour form and condense on different areas as the temperature goes up and down. Water is a bitch for that!

I'm going to get a used fuel pump unit and replace the one that's in it. I'm fairly sure that's the problem for it not starting now. (here's hoping anyway...)

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Re: A wee problem or two. Think they might be related?

Postby 93_Clubman » Tue Dec 11, 2012 10:11 am

eDrive.ie wrote:I'm going to get a used fuel pump unit and replace the one that's in it. I'm fairly sure that's the problem for it not starting now. (here's hoping anyway...)

Ref fuel pump - have a quick look at this related issue which effects NA & NB:
viewtopic.php?f=55&t=46425

eDrive.ie

Re: A wee problem or two. Think they might be related?

Postby eDrive.ie » Thu Feb 21, 2013 9:45 pm

Thanks for all the help. I've been too busy with family etc to do much on this, but I'll give you an update on where I am with this.
1. The car is completely dry.
2. The CPU seems totally fine, no corrosion, no chips or blistering or burns and I've used electrical contact cleaner on all contacts and sealed them with vaseline.
3. I've replaced all fuses inside the cabin and inside the engine bay. The headlights and electric windows are both working now. There's no other malfunctions on the car.
4. I've removed and checked the fuel pump, the two fuel filters and the petrol in the tank is totally clear. No debris or dirt inside and the secondary fuel filter is clear. I can blow air through it. If I attach a battery to the pump, it works fine.
5. I've checked the electric source at the main fuses in the engine bay and there is power at all fuses.
6. I've attached the Fuel Pump fuse terminal to the pump and it works.
7. I've removed the 4 wire-6 terminal, green fuel pump relay located under the accelerator pedal and connected it to a battery. It works.

Summary. There seems to be no power going between the fuel pump fuse and the fuel pump relay as both ends are working, but there is no power connecting the two.
My question is: Is there another component between the fusebox and the fuel pump relay that may have failed? Or would it be likely that a wire has suddenly broken or come loose in this section?
The car was running idle at the time of the problem, but it just stopped dead suddenly. It turns over, but doesn't fire.

Thanks

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Re: A wee problem or two. Think they might be related?

Postby 93_Clubman » Fri Feb 22, 2013 12:00 pm

Previously:
eDrive.ie wrote:I put in a new battery, cleaned the spark plugs and it started first time.

Then after 20 mins it just suddenly stalled and won't start. It'll turn over alright, but the car won't come to life. It's not receiving fuel even though it has petrol in it.

Currently:
eDrive.ie wrote:4. If I attach a battery to the pump, it works fine. Good, but have you tested the top of the tank electrical connections for continuity? See here:
viewtopic.php?f=55&t=46425

5. I've checked the electric source at the main fuses in the engine bay and there is power at all fuses. But is the Fuel Injection relay working?
6. I've attached the Fuel Pump fuse terminal to the pump and it works. Again, but is the Fuel Injection relay working?
7. I've removed the 4 wire-6 terminal, green fuel pump relay located under the accelerator pedal and connected it to a battery. It works. Good

There seems to be no power going between the fuel pump fuse and the fuel pump relay as both ends are working, but there is no power connecting the two. Might be reading this wrong, but if both ends are working then that suggests that it's ok up to & including the fuel pump relay & that the issue is between & exclusding the fuel pump relay & the fuel pump. If so, again see here: viewtopic.php?f=55&t=46425

My question is: Is there another component between the fusebox and the fuel pump relay that may have failed? Or would it be likely that a wire has suddenly broken or come loose in this section?

The car was running idle at the time of the problem, but it just stopped dead suddenly. It turns over, but doesn't fire.

Apart from what I've included above, given all the work you've done over a fairly long period of time, I'd also recheck for spark & fuel by trying to start the car a few times, then removing a sparkplug to check if it's wet, & finally with the sparkplug removed but still connected to the sparkplug lead, try starting again to confirm you're getting a good spark.

eDrive.ie

Re: A wee problem or two. Think they might be related?

Postby eDrive.ie » Sun Feb 24, 2013 10:16 pm

93_Clubman wrote:Previously:
eDrive.ie wrote:I put in a new battery, cleaned the spark plugs and it started first time.

Then after 20 mins it just suddenly stalled and won't start. It'll turn over alright, but the car won't come to life. It's not receiving fuel even though it has petrol in it.

Currently:
eDrive.ie wrote:4. If I attach a battery to the pump, it works fine. Good, but have you tested the top of the tank electrical connections for continuity? See here: - Yes. There's continuity there and tracking back up to the Fuel Relay above the accelerator pedal. There's no continuity between the Fuel Relay connector and the fuse box in the engine bay.
viewtopic.php?f=55&t=46425

5. I've checked the electric source at the main fuses in the engine bay and there is power at all fuses. But is the Fuel Injection relay working? Yes A new relay fuse was installed and there is power at the Fuel Injection fuse terminal.
6. I've attached the Fuel Pump fuse terminal to the pump and it works. Again, but is the Fuel Injection relay working? Yes, it's a replacement fuse.
7. I've removed the 4 wire-6 terminal, green fuel pump relay located under the accelerator pedal and connected it to a battery. It works. Good

There seems to be no power going between the fuel pump fuse and the fuel pump relay as both ends are working, but there is no power connecting the two. Might be reading this wrong, but if both ends are working then that suggests that it's ok up to & including the fuel pump relay & that the issue is between & excluding the fuel pump relay & the fuel pump. If so, again see here: viewtopic.php?f=55&t=46425 No. It's okay going from the pump back to the relay (which is working.) There is no power between the back of the replay and the fuse box (Fuse is also working) There must be a breakage or something else has gone between the fuel pump relay and the fuse box.

My question is: Is there another component between the fusebox and the fuel pump relay that may have failed? Or would it be likely that a wire has suddenly broken or come loose in this section?

The car was running idle at the time of the problem, but it just stopped dead suddenly. It turns over, but doesn't fire.

Apart from what I've included above, given all the work you've done over a fairly long period of time, I'd also recheck for spark & fuel by trying to start the car a few times, then removing a sparkplug to check if it's wet, & finally with the sparkplug removed but still connected to the sparkplug lead, try starting again to confirm you're getting a good spark.
- Good point, I'll do that, but I feel we haven't identified the problem yet. I've not "fixed" anything, so the spark plugs etc shouldn't be an issue just now as there isn't fuel getting to the chamber as there's no power getting to the fuel pump. My question is - Is there another component that may have failed between the fuse and the replat above the accelerator pedal? Or is it likely that there has been a randon breakage or disconnection in the wires between the fuse box and the fuel pump relay? Given that the car was damp, I'm thinking condensation may have caused a short in the section?

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Re: A wee problem or two. Think they might be related?

Postby 93_Clubman » Mon Feb 25, 2013 11:45 am

Not saying you've fixed anything, but am saying that out of all the things you've done over a long period of time something might have changed, hence the need to reconfirm spark, or confirm spark if you hadn't previously.

To clarify there are two relays & a fuse involved - there's the 'fuel inj' fuse & the 'fuel inj' relay ('EGI' relay on the NB8) in the engine bay fuse & relay box.

And under the driver side dash there's the 'fuel pump' relay.

If you have a look at page eight of the US MY1999 NB8 wiring diagram pdf you'll see the links between the fuel pump relay, the fuel inj (EGI) relay, the fuel inj fuse, & the ECU:
http://neomiata.com/garage/Wiring%20Dia ... agrams.pdf

Page four also shows the fuel pump relay linked to the ECU, & the diagnostic box in the front of the engine bay.

So in response to your question, from looking at the wiring diagram it would appear the the issue could be in the ECU or in the wiring to the ECU from the fuel pump relay, or in the wiring between the fuel pump relay & the engine bay fuse & relay box. None of which are common issues, but then again what your NB8A has gone through isn't too common either.

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Re: A wee problem or two. Think they might be related?

Postby bruce » Mon Feb 25, 2013 1:38 pm

I'd be trying swap in a good ECU (at least it eliminates one possibility).
An ECU might 'look' good but there might be damage not visble.


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