Hi Guys

For longer than I can remember, every now and again I get a slow crank then engine start-up, Never when the engine is cold. more so when the engine is upto optimum temperture. Last week, my car was sat unused for 5 days. Whilst I was away with work.

I returned home last Sunday, to a frozen windscreen (Its approaching Mid April!!!) Anyway, car started the 2nd I hit the Start button, I always hit the button to turn off Stop/Start tech. Later that sunday I had to go out and do a little bit of shopping. Jumps in the car, hits the Start button, 'Check Tyres' error popped up. Fine, I thought, until i looked at the dash. it was pointing at all 4 tyres. (All 4 were fully inflated, just needed reset)

On Monday, I got up as normal in the morning, Took my boys to school, then headed off to get the bits I'd forgot the day before from the local Aldi, engine had been running 30-40 mins from leaving home to getting to Aldi via the kids school.

Once finished in Aldi, put the shopping in the car, hit the Start, and all I got was slow crank. but no engine start. Then 'Starter/Ignition Fault, Engine cannot be started' on the centre screen. So called recovery, who appeared an hour later, jumped in the car, it started immediately, even though i hd tried a few times before he got their.

His opinion was either, Battery or Starter. when I eplained it had similar issues in the past. he said it'll be a lazy starter. But could be battery. So, I bought a battery tester. This confirmed a battery Low reading. Happy I'd found the problem I went and bought a new battery.

Out of pure curiosity, once I'd pulled the old battery out. I put the battery tester on the OLD battery. Tester read FULL

by this point I had connected the new battery. So, put the tester on the new 1, whilst connected........... The tester read 'LOW'

Now confirming the battery is not the issue.......... Has anyone had the issue. Had it resolved. I'm not convinced it is the starter as it doesn't do it every time.

Thank for any help or advice.

Morning Martyn

Welcome to the Forum

Just reading your post you may have diagnosed your own problem

If a fully charged new battery reads low when connected there is possibly a fault in the Earth Circuit Check the battery earth lead connections, not just if it's loose, un-bolt it clean it and remake the connections then check the Engine earth straps same scenario remove check them carefully clean the joint and remake them. Then do the same with the starter circuit. Once done remake all connections and test if the fault is still there Check the power lead connections at the battery and under the bonnet at the charge point

Hope this helps

Dave

Thank you Dave.

Would a bad earth give a slow crank when the car is hot. The car starts perfectly fine when the engine is cold. And must of cooled down enough for it to start immediately when the AA attended and started the engine

Hi Martyn

As you stated in your post that the battery was charged and new but when connected to the car showed low on your tester That would point towards a fault in the starter circuit which is why I suggested the checks I did a poor earth or loose connection will increase current draw dramatically plus they are free 😁

Starters do fail I have seen a few that at start drew very high current causing poor starting check the starter Relay and all connections. To be sure you will need a full Diagnostic scan

Dave

Thanks Dave I will have a look at the connections

Just had a brief look by the battery compartment, the circled wire is extremely loose compared to the others.

Purely through curiosity as well. What is this for, obviously powers something.

Morning Martyn

Without checking a wiring diagram not sure which circuit that would be but just looking at the cable size obviously a major supply. I would disconnect the battery and investigate how its fixed and why its loose. Loose connections create heat and increase current draw and eventually damage to the connection itself.

Dave

Looking at it yesterday it clips in but the wire into the clip itself is where it is loose. I’m away for a few days with work again so when I get back. I will disconnect the battery and investigate.

Just having a brief look on Google at what the red box is……….. so I think this is definitely number 1 priority as to where the problem is

Morning Martyn

When you get back try starting the car get it up to temp then feel that cable and connection for any heat

Dave

I got back late the other night. Felt the wire once I got home. Journey home is approx 20 mins, including motorway. Didn’t seem to be any heat in the wire, nor did any of the others.

spoke to someone earlier today who is having the same issue with his BMW, he said it is 100% the starter

Morning Martyn

I am still confused as you said you connected a New Battery and tested it, it showed low voltage ? Had you tried to start the car before your test ? You also told us that off the car the old battery tested full ? Had it been charged or was it tested straight from the car ? When testing the battery what voltage are you seeing ? 12.5v + Battery fully charged 12v around 80% 11v or below Battery is discharged or dying

So if it isn't a loose connection in the power supply and all earth connections are good and the battery is still fully charged the Starter and its Relay are left. I would still run a Diagnostic check to be sure

Dave

You and me both mate, the car does start. Apart from last week when I had to get the AA out. The AA man stated it was either battery or a lazy starter.

I read up online that a discharged battery can give similar issues that are misdiagnosed as a starter issue, which prompted me to buy a battery tester. This then showed the connected battery as low. I therefore went out and bought a new battery that tested full before connecting to the car.

Out of pure curiosity I tested the old battery when disconnected, which then showed as full, same with new, low when connected, full when not.

it’s not only confusing, it’s extremely frustrating, thankfully the battery had a 60 day money back guarantee, so did manage to get my money back.

The car has been fine since the problem resulting in the AA attending. But it has been in regular use again. I am away with work again next week for a full 6 days, so will see what happens when I return and report back

Thank you for you help Dave, it is really appreciated 😁