astra mk V, 1.6 petrol, about once a month it just wont start, ignition turns over but wont fire. can bump start it and then it’ll restart after running for a few minutes. Runs fine rest of time, no warning lights. Used to belong to FiL he said he’s not had any issues with it.

Any ideas before I sign up for a load of cost and rigmarole trying to get a garage to diagnose it?

Mum had a very same model, hers didn’t start once after moving car a short distance (moving parking spot) but by time AA got there he got in and it started up fine. Had a google and saw a couple other weird not starting stories from astra owners but they said after leaving it for an hour or so it started up ok.
Last time this happened I left it ages and still wouldn’t start – had it 3 months or so and this is only 2nd time it’s happened.

does it have immob light on dash?

Have a spare spark plug handy. Next time it doesn’t start, whip a HT lead off one of the spark plugs and onto your spare plug (make sure you hold the rubber HT lead) and turn the car over again. If the plug is sparking the issue is with fuelling, if it isn’t sparking it’s an ignition fault.

My guess would be it’s a crankshaft sensor fault, that is just a guess though!

does it have immob light on dash?

pretty sure it doesn’t

haven’t got one handy leeerm but sure I could get hold of one

u need a fault code reader – not every time u get a light but it might register if there has been a specific fault, you want a proper Vaux diagnostic rather than a random generic. I would advise maybe find a Vaux forum and see if theres someone who will check for some beer money, I have ford, mb, bmw and vag but no Vaux sadly

Well you’ve got power so battery and alternator are not an immediate issue. And when it’s running it runs.

Plug leads /coil pack would be the obvious suspect.
If it’s very intermittent, it might be worth checking there’s no corrosion or water ingress on spark plug terminals etc.

I had this with a car once (a mk4 1.7 diesel astra) – could hear the starter motor going, but nothing else. It turned out to be a damaged/worn starter ring gear.

It only manifested itself when the worn section fell in the right (wrong?!) place, hence bump starting worked (and possibly just rolling the car along a few meters until the ring moved around enough), and it then usually started fine for some time afterwards, until the worn section of the ring placed itself badly again.

good idea sammy

matty yeah battery seems fine, plenty of charge

(and possibly just rolling the car along a few meters until the ring moved around enough)

can’t remember if I tried this last time, will give it a bash, any ideas what sort of distance I should move it?

It’s a heavy bugger to push tho 🙁

And you’d need to move it in gear for that to work.

Watching this with interest, i have 2006 1.4 petrol Astra Estate, mine does the same, but has never not started. Always have to take the key right out and put back in to get it to start and it only seems to happen if car hasn’t been used for a few days?

Loose earth cable on the battery gave me symptoms like that.

I had an issue a number of years ago with a petrol Renault Megane. Similar symptons to what you’ve described. It only tended to happen duriong the warmer & drier summer months.

Got the AA out a couple of times, first guy couldn’t figure it out, second one sorted it within 2 minutes. Turned out there was a build up of static on a crankshaft position sensor (if I recall right, it was about 10 years ago). All you had to do was touch the sensor to discharge the static and problem solved!

And you’d need to move it in gear for that to work.

Oof! Maybe not then.

Cars are complicated, contrary buggers eh?

can’t remember if I tried this last time, will give it a bash, any ideas what sort of distance I should move it?

And you’d need to move it in gear for that to work.

That rings bells, it was about 13 years ago so can’t remember how that bit worked exactly. I remember the car got parked on a hill quite frequently in case an impromptu bump start was needed 🙂

Another Megane owner here and had / have a similar issue. With my Eurobox, it seems to be a fuel pump issue. Solved by eventually finding a little priming pump which you squeeze by hand a few times – works every time but a bit of a pain.

Weirdly, only happens if I park on a hill with the bonnet pointing uphill.

choke? I assume electronic choke right enough.
My second car I got from my dad, ad he was a poor driver now I realise it. He’d hold stuff in too low a gear for ages, and the car had a sticky butterfly choke – and got confused when you restarted the car after an hour – from hot, fine, from cold, fine, but tepid starts were a nightmare.

Glad to see the bad of it – Citroen BX.

just wondering about that damaged starter ring gear suggestion. How far would I have to push it? Thinking about instead of just bump starting it trying to move the ring to an undamaged bit – figure out if that is the issue or not. Presumably stick it in 5th and push it forward a bit, neutral, try ignition again, if it fires that’s the likely culprit. So will couple of feet do it? or would I have to shift it a fair distance?

It has THE DEMONS! Throw it in a pond and see if it floats, for conclusive diagnosis. If it sinks, it was demon-free

Think you may have it Northwind. service, oil and engine light lit (battery aswell obviously) when trying to start the car – still nothing, bump started it, took a couple goes but once started no warning lights, drove it for a bit, had some things to drop off, no issues, got home switched engine off for a few mins, started up again fine.

I guess it’s off to the garage for an inspection, intermittent faults difficult and expensive to diagnose 🙁

just wondering about that damaged starter ring gear suggestion. How far would I have to push it? Thinking about instead of just bump starting it trying to move the ring to an undamaged bit – figure out if that is the issue or not. Presumably stick it in 5th and push it forward a bit, neutral, try ignition again, if it fires that’s the likely culprit. So will couple of feet do it? or would I have to shift it a fair distance?

I think if that is the issue you should be able to test for it by popping the car in first (and not depressing the clutch), if the starter is working properly and the ring is undamaged the car will lurch forward. If you don’t seem to move then either the starter isn’t turning or its not meshing with the ring…