E30 Zone

I’ve had an issue for the last few years that is not major but it is annoying because I can’t find the cause.

When driving off from cold the car suddenly jerks and engine seizes for a split second. It’s more than a standard cut out as if I switched the ignition off for a split second, it’s as if the engine actually jams.

It started after I cleaned and serviced the injectors a few years ago. I’ve replace the fuel filter. No idea what it is. I’m assuming a full leak somewhere but I don't smell fuel.

Any advice is welcome!

Thanks guys.

Is this 'cut out' indicated by the tacho needle?

Mine did this...but at random times - usually when cold.

I cleaned the AFM track and moved the wiper a little and it was better - but the fault showed up again and became really bad - I replaced the entire AFM and it's never done it since.

It feels like a half second with the ignition off - really horrible if you're accellerating hard in second!

But first check your AFM plug and socket - clean? connections all good?

Paul

Brianmoooore wrote: ↑

Sat Apr 25, 2020 8:59 pm

Is this 'cut out' indicated by the tacho needle?

Thanks Brian, think the tacho needle drops if I recall correctly.

paultv wrote: ↑

Tue Apr 28, 2020 10:19 am

Mine did this...but at random times - usually when cold.

I cleaned the AFM track and moved the wiper a little and it was better - but the fault showed up again and became really bad - I replaced the entire AFM and it's never done it since.

It feels like a half second with the ignition off - really horrible if you're accellerating hard in second!

But first check your AFM plug and socket - clean? connections all good?

Paul

Thanks Paul I’ve not looked at AFM it’s usually accelerating in 2nd 200m down the road and it’s like someone’s hit the break...sounds a lot like what you describe.

Unfortunately, you've given two condradicting aswers in the last two posts.
If the tacho. drops out, then it indicates an electrical fault to the ignition control circuits, such as a crank position sensor beginning to fail, or a dodgy DME relay.
An AFM fault would give a problem with the fuel injection side of things (either too much or too little fuel), and wouldn't affect the tacho. at all.

Brianmoooore wrote: ↑

Fri May 01, 2020 10:59 am

Unfortunately, you've given two condradicting aswers in the last two posts.
If the tacho. drops out, then it indicates an electrical fault to the ignition control circuits, such as a crank position sensor beginning to fail, or a dodgy DME relay.
An AFM fault would give a problem with the fuel injection side of things (either too much or too little fuel), and wouldn't affect the tacho. at all.

Thanks Brian, I'll try it today and confirm what is the case, I appreciate your knowledge and expertise.