I have a weird problem with my car.

its sat in the garage over winter and has developed a starting fault.

it cranks over fine but won't start (no spark, injectors or fuel pump). Jump it from another car thats running and it'll start straight away.

I've cleaned up all the battery terminals, tried a spare crank sensor, still the same. With the ignition on there is 5v at the map sensor so the ecu is getting power.

The only thing that makes sense to me is a relay somewhere sticking that switches when it gets the 14v from the other car but i dont know which one? I don't think its the ignition relay as wipers, lights etc still work ok.

Its also a bit intermittent as sometimes it will go without a jump but it cranks for longer than it normal before starting

Anyone got any ideas as I'm stumped and its doing my head in!

 

Yellow ecu relay try that. There are 2 on the engine loom ecu and fuel pump.

 

The engine loom relays was the next thing i was going to check.

I thought the ecu relay was the purple one and fuel pump the yellow?

 

Both yellow but be carefull some have different pin outs. Fuel pump one has a thick ish black with red trace.

Paul

 

Ok thanks, i shall have a look tomorrow.

Is the purple only on earlier 3 door or later 4x4 looms?

Although i appreciate its going to be something silly, it's a really annoying problem!

 

Purple is i think abs.all engine looms i have seen both been yellow relays.

Hope you sort it.

 

Ok, I'll let you know what i find.

From what i can see looking at wiring diagrams they are both std 4 pin normally open relays so shouldn't be difficult to

 

Presuming the battery is good? Have you checked voltage across it while cranking?

 

The battey is less than a year old. I realise that just because something isn't that old doesn't mean it won't go wrong but if it cranks over ok I've just assumed that the battery isn't the problem?

i need to get hold of some square to round terminal convertors to try another really

 

Give the battery a proper load test. If it isn't giving a good 12v+ during cranking the ECU will be down on power, you will loose your spark etc etc. I would give all the main earths a check, battery to chassis, engine to chassis.

 

Ok I'll do a load test on the battery. Was chatting to a mechanic mate last night and he suggested the same thing.

Ive tried to eliminate the earths by putting a jump lead between the battery and various points on the body/engine and it hasn't made a difference?

I think it's got to be a relay sticking or battery voltage causing problems somewhere as its the only thing that explains why it goes by jumping it.

Its the fact it cranks over normally that i don't understand?

 

Well it appears it was the battery.

voltage dropping off to 8.something when cranking.

Borrowed the battery off the wifes focus and it appears to be ok?

Never come across this issue before, clearly enough cranking amps but a lack power. Was a proper yuasa battery too approx 10 months old!

 

Cool easy fix.

 

Yeah!

Thanks for the help lads