Difficult starting

[lovema75]

Can I have your collective wisdom on my new purchase, and why it struggles to start?

Hot or cold it requires a tremendous lengthy application of the starter. Also when its started from cold, it often starts on 4 or 5 cylinders and sounds really rough for the first minute. As it warms up it gets smoother and runs better.

I know the engine wont be in tip-top health, its been used and abused, in particular its done a lot of towing. I dont think there is any head gasket issues, there are no signs of oil and water mixing or change in levels, no overheating, and there is plenty of go when under way, probably more than in my last car.

Is it possible there are 1 or more sticking valves, in which case is it worth trying some hydrolic valve lubricant added to the oil?

Any suggestions greatly appreciated.:bowdown::bowdown::bowdown:

[Devilish]

Not that I know much or would ever want to kmow much about petrol engines, but I would start with choke and air filter. Valves do not unstick with temp change, air intake changes dramatically

[mh007]

As you say it starts on 4 or 5 cylinders, i'm assuming you have a KV6.

There is no choke to speak of.

I would start with checking/changing the spark plugs as they probably haven't been changed in a while (especially the rear 3 !)

There are other things that would give you your problem but I would start with plugs.

As oil/filter change may do it good too, in fact, it may just need a really good service !!

[lovema75]

Yes I will start with that ASAP!

Just hoping its nothing more serious mechanicaly.

As for valve stick, temperature can indeed make a difference - years ago an 820i I had always started from cold with sticking valves which freed off as it warmed up. Just lived with it!

[mh007]

Your issue with your 820i was more than likely down to grade of oil used.

I had quite a few in with random misfiring when cold over the years & still get them now.

They used to suffer with carbon build-up on the valves.

As the engine warmed up, the carbon softened allowing the valves to close fully.

A flush with a decent additive (injectors & engine), new oil & filter & problem cured.

In real extreme situations, I had to remove the cylinder head.

I honestly think your problem is external though & not head gasket.

[Dashiel]

As stated by others your car needs a full tune up
Spark Plugs ,ht leads to start with.
then if it still persists i would get a known good front coil pack and work down the front bank, replacing and testing. Then move onto the rear bank.
thats for starters.

[Dashiel]

Ps
Are you losing water or oil?

[James.uk]

I once had a Mazda 323f exec that was very sluggish to drive, I used some Fortes valve cleaner stuff and it transformed the car. Was brill afterwards.. :D
...

[lovema75]

Ps
Are you losing water or oil?

No I've monitered it but doesn't seem to be loosing any fluids, and there is no sign if mixing either.

A good service is certainly first place to start, but wondered also if there was anything else, like cam sensor that could be causing issues. I have some spare coil packs from my last car so I will check them as well.

I think it's been rather neglected.