Engine management light

[Wafu]

I’ve read threads regarding this error but I thought I’d ask anyway

I've got a 68 plate Caravelle with a tad over 40k on the clock, it’s getting close to a service and low and behold whilst driving to work (about a 30mile journey in Cornwall) the engine management light flashes on. At the same time as this, I get a slight kick in the van and a loss of power, enough to get up the hill but a noticeable drop in performance.

Great I thought, I can use my new toy, the Carista obd I bought from Amazon. I plod on to work with reduced power and pull into the car park. I turn off the engine and got the Carista out of my glovebox, I put it into the port and turn the ignition on. We’ll blow me, the lights gone off, never mind I’ll see what the problem is on the App. The third surprise is nothing showing on the App in the ECU, in fact nothing at all, my van’s health, according to Carista. I tried a little drive don the road and surprise surprise Cilla, nothing wrong with the van, the lights gone and all the power is where it should be.

Over the past week on the drive too and from work, i‘ve sometimes had the light (only once during the 30 miles and always gone off if I turn off the ignition and restart) and frustratingly sometimes never.

What’s going on?

My questions are;
Has anyone else suffered from this And if so what was the cause/remeddy?
Can I plug the Cresta in when the engine is running to see what’s happening with the engine management?

Thanks in advance for the comical and serious replies.

 

[T6Paul]

No loss of power but I have had the EML come on and go off randomly all by itself on several occasions!

 

[Wafu]

All fixed, after interrogation by VW it seem the Turbo actuator was giving out. New actuator fitted and its back to its old self

 

[bluezie]

This a reason why I use VCDS ,not cheap diagnostics! If the check engine light came on, there will always be fault codes stored, even if the fault clears itself.

Personally, I think the diagnostic kit is one of the most important tools for working on modern vehicles, so it needs to be 100% reliable. Even expensive kit will pay for itself very quickly, and if you do your own servicing, then a full vehicle scan is part of it, as often there are fault codes stored with no dash warning lights triggered. These are designed to be low level faults picked up and actioned during servicing. Cheap OBD II kit can't scan anything more than the engine ECU.