Woke up after hibernation - check engine light on :-/

Pures3 · Post by **Pures3** » Sun Mar 31, 2019 8:52 pm

Woke her up today after a winter slumber. Car started first time but the check engine light came on.

Left it running for a while to warm up, turned off and washed it.

After a nice clean, it wouldn’t start! It’s been on the ctek over the entire winter too! Put the battery back on charge for a few hours. Started right up again, but wouldn’t idle properly. Revs bounces between idle and about 1500 rpm? Check engine light was also still on.

Cars back in the garage and on charge again. AGM setting in the ctek.

The only thing that has changed is I’ve fitted an Eventuri over winter.

Any ideas? Dodgy MAF maybe? Fitted a new battery last summer.

Post by **srhutch** » Sun Mar 31, 2019 9:36 pm

You’ll need to scan the codes to be sure, but if your battery is shot then your symptoms are similar.

john-e89 · Post by **john-e89** » Sun Mar 31, 2019 9:42 pm

Just changed the ignition switch on mine as it had a parasitic battery drain which had the symptoms of a knackered battery. All cured and running sweetly now.

That’s just one course of action however, as SR Hutch says could be the battery itself.

Chris_D · Post by **Chris_D** » Sun Mar 31, 2019 9:54 pm

Sounds like a shot throttlebody.

Spaniarduk · Post by **Spaniarduk** » Mon Apr 01, 2019 8:29 am

Chris_D, and which one of the 6, purely mechanical ones, would that be? I kindly disagree. After months of hibernation it is highly likely to be a duffed battery. Ive heard of other people reporting similar symptoms due to faulty battery.
The first approach would be to get the fault codes stored in the engine's ecu. All else is just speculation

Chris_D · Post by **Chris_D** » Mon Apr 01, 2019 2:07 pm

Spaniarduk wrote: ↑Mon Apr 01, 2019 8:29 am Chris_D, and which one of the 6, purely mechanical ones, would that be? I kindly disagree. After months of hibernation it is highly likely to be a duffed battery. Ive heard of other people reporting similar symptoms due to faulty battery.
The first approach would be to get the fault codes stored in the engine's ecu. All else is just speculation

oh, didnt realise it was an M. My bad.

Spaniarduk · Post by **Spaniarduk** » Mon Apr 01, 2019 3:34 pm

Chris_D, ok, we'll let you off

Pures3 · Post by **Pures3** » Mon Apr 01, 2019 9:50 pm

Quick update...

Put the car back on charge and let the ctek take it to phase 7 (where it holds the charge for 10 days).

Took the car out for a spirited drive and it was absolutely perfect. Check engine light was still on, I think I will just need to reset the error code tbh.

I think it was the battery! I suspect I took it off charge mid cycle...or at the point where it’s discharged the battery.

Post by **srhutch** » Mon Apr 01, 2019 10:03 pm

Make sure you have cycled the ignition have a dozen times, starting the engine each time.

If it was the battery and it’s ok now it’s been properly charged the lights will go out with the ignition cycles.

Jembo · Post by **Jembo** » Wed Apr 03, 2019 8:19 pm

I started by using a solar charger then totally disconnected the battery over last 3 months.

Had to spin her up last weekend & not a single issue (touch wood & save clock/window reset) so I’ll probably just remove the battery & store it in the shed on the solar chgr next winter.

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