K-Series - Won't start, no fuel on fueline

[Kimble]

I was supposed to be going to Brands today but my car won't start this morning.   I was wondering if people might be able to help me diagnose.  It's a 2004 R400 K-Series.

I got caught in a downpour yesterday but the car started a few hours later and started ok this morning but then stopped after a few seconds, I can only assume through lack of fuel.

Car whirs and clicks after ignition.

I'm pretty sure I have ignition as some wd40 in the RB's seems to ignite.  I have dried plugs in case there was any water ingestion from yesterday.

Disconnected the fuel line and there is no fuel being delivered.

I know my cut off switch has been a bit temperamental lately but my understanding is that if the immobilizer/switch is failing then that will kill the injectors and not the pump/fuel line.

I have pressed inertia switch and cleaned/checked the crank position sensor.

Battery is new and charged.

Now I would assume the fuel line to be flowing when I try and turn the car over so this is current point of focus.  Can anyone give me any pointers?

 

 

[TomB]

Have you check your fuses? 

The whiring and click after ignition - are these coming the fuel pump?  When the ignition is turned on the pump should prime, with associated whirring from the back of the car.   

[Jonathan Kay]

Fuel pump fuse, as above. Please let us know if you need a diagram of the layout.

Listen to fuel pump, as above.

Check fuel level in tank.

Is the ignition light coming on as usual?

What's the battery voltage at rest and as you try to start?

Do you have another vehicle or battery that you can use to jump start?

Try wiggling the key around in the column lock before starting.

Jonathan

[SM25T]

Check all fuses, then check for 12V to fuel pump when ignition on. The original ECU fuse was 20A but should be changed to 30A on CC advice. 

[Jonathan Kay]

"Check all fuses, then check for 12V to fuel pump when ignition on. The original ECU fuse was 20A but should be changed to 30A on CC advice."

Yes.

Jonathan

[Kimble]

Should have said:  Checked fuses

Really strange.  I left the car for an hour or so with the fuel line disconnected and fuel started flowing.  I can only assume something was wet or had a poor connection and the heat dried it out.

Thank you for the assistance.

[Jonathan Kay]

Thanks for adding the outcome.

Jonathan

[Kimble]

And the problem is back so there is definitely something wrong, my to do list to check is:

• FIA Master Switch
• Fuse
• Connections from/to fuel pump

I'll let you know what I find as no doubt this is a gremlin of some kind.

[Jonathan Kay]

Yes, those are all good lines (!) of enquiry. There's a few more suggestions upthread that might save you time.

Jonathan

[Wrightpayne]

When I built mine I had problems with power to the fuel pump. There is a crimped connector in the loom just down from the inertia switch plug which was faulty - green/yellow wire (or was it yellow green??)

You will need to undo the tape a bit to find the connector (assuming it is this) - a wriggle of the loom might cause the pump to spring into life!!

 

Found this - its Yellow with Green tracer! The bit of black tape on said wire shows where the joint is, just outside of the main loom (its EU2 BTW)

 

[Kimble]

Ok, new developments.  Car still won't start.  Status as of now is:

• Fuel flows on fuel line (filled an inch in a beer bottle quite quickly and seemed to pulse a little when I turned it over.
• Piggybacking the fuel pump connected with a meter shows about 10.5v when I try and start.
• I've taken a spark plug out and there is a spark when I try and turn the car over.
• If I spray some wd40 in to the roller barrels or a little fuel then the engine fires a little.
• with a meter on the connector to a fuel injector I can see some voltage spikes when I try and start
• fuses all look ok

I'm completely stumped now.  I've put the battery on charge now in case I have drained it.  It's dropping to around 10.7 when I try and start.

All I can think of now is that it's perhaps the crank position sensor.  I've tried to clean/jiggle the connector but no change.

Any more ideas?

 

 

 

[Jonathan Kay]

10.7 V on cranking is quite low. Many Sevens won't start below 10.5 V because some electronic widget or other drops out.

What sort of battery is it, and if it can be topped up what are the fluid levels?

Do you have another vehicle or battery that could be used to help it and to see if that makes a difference?

Have you checked the connections at the battery, including wherever it's earthed? And the earth to the engine block?

Jonathan

[Jonathan Kay]

"Piggybacking the fuel pump connected with a meter shows about 10.5v when I try and start."

Where's the other side of the meter connected when you do that?

 Have you checked the earth to the pump?

Jonathan

[Kimble]

Thank you for your help Jonathan.  You really do go above and beyond the call of duty here! :)

It's the standard banner and very new but I might have drained it a bit with the endless starting attempts. I've left it on charge so will give it another go in the morning as I've given up due to low light.

The fuel pump measurement was performed across the pump wires. I assumed it was a + - terminal as I couldn't really see how else it would work.

Battery connections all look good.

I've taken the crank position sensor off and cleaned it.  Does anyone know how to test their function?

[revilla]

Fuel flows on fuel line (filled an inch in a beer bottle quite quickly and seemed to pulse a little when I turned it over.

Where are you checking this? At the fuel line IN to the fuel rail (at the rear) or at the return line OUT from the fuel rail (at the front)?

If at the supply line at the rear, I would expect fuel to be delivered VERY rapidly. An inch in a beer bottle would be a split second with a healthy pump. Best to check the return line at the front, as this will tell you whether the fuel pump is delivering enough performance to pump the fuel rail up the the rated pressure of the fuel pressure regulator. At low demand such as when cranking to start, you should still get quite a strong flow here.

I don't have numbers for our pumps to hand but from a quick Google search, most pumps seem to flow somewhere around 350 litres per hour at 45psi, which is 100cc per second, so that's the kind of flow you would expect even at the return hose.

Having said that, if there's ANYTHING coming through the return hose then the pump is delivering enough pressure to open the regulator and you should be able to start it.

The only other way to really know if the fuel pressure is good is to fit an inline fuel pressure gauge in the fuel supply hose, but this does involve cutting the hose and I've heard from someone who I did this for that the scrutineers didn't like it at competitive events.

[Kimble]

I think this is the return line as it has a jubilee clip holding it on and is situated just above the TPS on the roller barrels.  The other end, that I tried to take out feels almost glued in and has a proper crimped ending so obviously mean to deal with higher pressure.

No change this morning after a charge of the battery.

I suspiciously can't hear any whirring from the fuel pump but I'm not sure I have ever really heard anything from the back of the car.

I have 12v off all three prongs of at the back of the FIA switch.

I'm thinking of dropping the roller barrels off and inserting a piece of paper to to see if the fuel injectors are firing.

[Wrightpayne]

You will (should) definitely hear the pump whirring when the ignition goes on.

[Kimble]

The plugs are quite wet when I clean them down and then turn the car over.  I seem to have a good spark as well.

I'm going to hook the PC up and see if there's anything amiss with the TPS.

Getting really stumped here :(

[Kimble]

Found it.

So there's a multi-connector below the roller barrels.   In one last time pass round the car checking connections before downing tools for the day I tried squeezing that whist turning the car over.  As soon as I did this the engine tried to fire.  On closer inspection it looks like a yellow/green wire into this connector wasn't properly seated or clicked in. I gave the connector a bit of a clean and made sure that wire is fitting better.

I can totally understand how this would create an intermittent issue and a complete bugger to find.  I'll look at the wiring diagram a bit later to work out what that is doing.

Thank you everyone for all your assistance.

 

 

[revilla]

It's the feed to the fuel pump!

[Kimble]

Ok, that would help explain the behavior I have been seeing.

Thank you.