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Car won't turn over - Suspected fuel pump

Posted: Thu Nov 10, 2016 10:51 am
by Staaahp
Went to fill up petrol yesterday and after filling up the tank the car would start up and idle for 2 seconds eventually dying.

2 cranks later the car refuses to start now. I've tried changing spark plugs and leads so far with no luck.

Anyone have any issues with the walbro 255 fuel pump just giving up out of the blue? Either that or I feel like it could be bad fuel.

Cars turbo running a chiptorque. May be an issue with the map perhaps.

Note: Car's never sees anything other than 98. First time using Speedway as I was in a rush. :cry:

Re: Car won't turn over - Suspected fuel pump

Posted: Thu Nov 10, 2016 11:24 am
by slyfox2151
Does it run if you use startyabastard? Easy and cheap way to test it...

Re: Car won't turn over - Suspected fuel pump

Posted: Thu Nov 10, 2016 11:49 am
by Staaahp
I'll drop by and pick up some on the way home.

Although, now that I think of it I can usually hear the fuel pump engage when turning on the electricals. I'm quite positive that sound is now non-existent. I'll double check when I get home nevertheless.

Re: Car won't turn over - Suspected fuel pump

Posted: Thu Nov 10, 2016 11:57 am
by StanTheMan
NA, NB NC?

do you have fuel & Spark

on the NA's NB's at least, you can isolate the fuel pump through the diagnostics box. You can bypass the relay. If the fuel pump is not working It may also be your relay.

If you have fuel & spark......that's another story

Re: Car won't turn over - Suspected fuel pump

Posted: Thu Nov 10, 2016 4:16 pm
by Staaahp
Ok so I just got home. Decided to try my luck and try one more time to start it before I fiddled around with stuff.

It seems to now magically run like normal. Cars running smooth with spark and fuel. Got fuel tested and it's fine. I honestly have no idea what's up at this point. Any chance of it being a blocked fuel filter or something?

NB btw

Re: Car won't turn over - Suspected fuel pump

Posted: Thu Nov 10, 2016 4:31 pm
by StanTheMan
could be your Relay or Fuel pump playing up. If you are certain you didn't hear it prime last time.

Ive had had a wiring issue as well as an intermittent fuel pump problem mine the past. Mine is an NA6
NB's are known for Relay issues

Re: Car won't turn over - Suspected fuel pump

Posted: Thu Nov 10, 2016 4:42 pm
by hks_kansei
When fuel pumps go it's not always and all or nothing thing.

It can come and go, usually it will work first off but after a drive (heating up) the pump won't start the second time.

I'd be checking the relay as mentioned, relays are cheap, and over time they do get sticky and cause issues.

Then look at the pump.

Re: Car won't turn over - Suspected fuel pump

Posted: Thu Nov 10, 2016 9:13 pm
by Staaahp
Thanks guys, i'll have a proper look at the relay and get it sorted out.

Really appreciate the responses.

Re: Car won't turn over - Suspected fuel pump

Posted: Fri Nov 11, 2016 7:52 am
by speed
Hope you get it sorted mate. Looking forward to meeting you and your car soon :)

Sent from my GT-I9506 using Tapatalk

Re: Car won't turn over - Suspected fuel pump

Posted: Fri Nov 11, 2016 8:10 am
by StanTheMan
To my knowledge and please correct me if I'm wrong, is that the relay generally doesn't go intermittent. Ive read some members keep a spare one in their glove box.

Re: Car won't turn over - Suspected fuel pump

Posted: Fri Nov 11, 2016 9:43 am
by hks_kansei
Not sure about the mx5 fuel relay specifically, but I've had relays go intermittently a few times.

They're essentially just a light switch that completes the contacts (not too different to points in a dizzy)

But because the switch is triggered by a small electromagnet, if the contacts get corroded or whatever, it can stick open or closed and the magnet can't pull hard enough to fix it.

Re: Car won't turn over - Suspected fuel pump

Posted: Fri Nov 11, 2016 3:40 pm
by 93_Clubman
If NB8A (ie 1998 to Sep 2000) then you might also consider one of the coils in the coilpack.

Re: Car won't turn over - Suspected fuel pump

Posted: Sat Nov 12, 2016 1:54 pm
by Staaahp
The car is a NB8A. I've had a chance to drive it around a bit to see if the problem still persisted, meticulously ensuring the the fuel pump was priming as intended. No issues so far.

Also had a closer look at the relay this morning but couldn't notice anything out of the ordinary. That being said, i'm definitely replacing it on Monday to not risk getting stranded again.

I have a set of LS3 coils going in very very shortly so that will hopefully eliminate the possibility of a malfunctioning coilpack! :D :NB8B: