Car doesn't crank when hot - ideas please!

[ereeiz]

I feel like I'm going mad. I start my car, no problem. Literally will fire up from about 1 crank. Whenever it cuts out after idling for 10+ seconds on its own it will no longer crank.

I'm still trying to figure out the circumstances that cause it, but I remember regularly reading other people having hot start and start motor issues.

Symptoms:

Happens when the engine has run for 1+ mins.
Solenoid will sometimes engage but starter will not crank
Solenoid will sometimes do nothing
I think the relay behind the glovebox is clicking (as in on when I turn the key, off when I switch it off....so working as it should) so I assume that is ok, as the solenoid (next item in the circuit?) will activate more often than not.

I found my -ve battery terminal was upside down and loose so replaced and tightened that. Tapped the starter and solenoid with a 19mm spanner (only thing to hand) I put it in gear and rocked it back/ forth, none of this made any difference.

Could it be the ignition switch? Can't see how as all that part of the circuit must be working in order for the solenoid to activate and the starter motor, when it wants to.

Could the starter be tired?
Starter mounted too close to the flywheel (requiring too much torque and overcoming the motors ability)
Brand new battery

I seem to only have the problem once the engine has run, regardless of whether it cuts out/ I turn it off.


Anyone got any ideas? I'll post back up my findings (if any) as/when I figure it out. I've only been driving it for a week, commute ~100miles/day on A/B roads. Tootling along off boost as the map is wrong.

The clock doesn't dim/cut out when cranking so pretty sure it's not dead battery. I haven't tested this though. Perhaps the battery has a bad cell in it?

[hayesey]

could be the ignition switch, sounds like the ignition part is working but not the start switch.  Could it be a dodgy starter too?  What condition is the wiring like to the starter?  Could be the relay itself too. I would get a multimeter and test those things.

[ereeiz]

Doesn't matter now, the gearbox shit itself yesterday I've put too much time and money into it for it to break! So pissed off!

I'm gonna park it up and deal with it in a month once I've calmed down. Also doesn't help not having a unit to store it and everything else (tools, parts) in, I've only been looking for one for 10 years!


I'll update when I figure it out. Might just fuck it all off and replace everything and do the aftermarket ignition/ECU upgrade at the same time. Ol' captain OCD over here!

[hayesey]

ah, gutted.  Prob best to leave it a bit like you say!

gearboxes are one of those things on a g40, if you own one for long  enough you'll end up needing to sort the box out.

What has happened exactly?

[ereeiz]

I bought it off Jezza as a rebuilt box as far as I can remember. I've not actually checked to be fair and I'm not whinging about it. The luck of the draw with second hand parts!
It's got a quaife in it so as long as that's alright I don't mind the rest.

I was doing 30mph (3rd), entering a 60 zone, lorry in front pulling over, I slowed to 20 (put it into 2nd) then accelerated to overtake, maybe got to 35 at a push, put it back into 3rd and tootled 1-200 yds up to a roundabout, still about 30-35mph in 3rd. Went to drop to 2nd as I was about to enter the roundabout, it sounded like when you get a tool bag and throw it at the floor as I was trying to get it into 2nd. Instantly recognised the sound of smashing metal on metal so popped it back into 3rd, clicked when it engaged (went in fine) and started making a thudding sound, dipped the clutch, put it into neutral and rolled into a layby, switched it off.

I got towed home by a mate after a 2.5hour wait, it freewheels fine.

It had a brand new clutch although I did think the release bearing was noisy.....perhaps it wasn't the release bearing.

I also would hear a weird cracking noise on boost in 4-5th gears. I only drove it for a week and off boost 99% the time as I was tootling to//from work. Perhaps the cracking noises I assumed were pinking was actually something in the box. Never felt anything through the floor/pedals though.

It's a mystery at the moment. I will be opening the box regardless though as even if I find it's something else I'm paranoid about it now and don't want to kill the quaife.

[NealPeal]

I am sorry about the gbox, nightmare

On the starter-front I've just had the engine out mainly to fix the starter that would only click (and an oil leak so hey it was coming out). We found he starter worked with it out the car but not wired up it.. There just wasn't the current available to drive the throw.
Either there's a relay missing, or it's got the loom off the new body and the alarm installers were mad, the Immobiliser is a VW one, definitely not factory fitted wiring!
….   the 2 FAT WIRES that fed the ignition switch had been split and joined to 2x20w speaker wires that went to the immobiliser connector and back…
The staple I'd stuck in place of the alarm got hot real quick and the starter would only click again  for a minute after 10 seconds of cranking (I found trying to start it with no petrol). Now I've stuck a clothes peg in holding the original wires together it fires every time. If I'd put the immobiliser in I'm sure it'd catch fire, it needs buffering definitely if I ever do put it in..

Cool, good luck!
NEAL :-)