Motorraum: VANOS noise fixed.......but another problem.

[Glacier]

2000 E38 740i M62TU 04.04 101.000 MILES .

Hi, apologies for not speaking German .

I had the 'startup rattle 'and a noise the same as this video:

 YouTube - ‪M62B35 Ticking‬‎

After a lot of research, I concluded that it was coming from the VANOS units.

The E38 M62TU engine should not sound like a diesel .......... right?

So, I bought two new units , No.1 :

 RealOEM.com BMW E38 740i timing gear timing chain top - VANOS

And two new oil check valves , No.8 :

 RealOEM.com BMW E38 740i Cylinder Head Attached Parts

Also the timing tools:



Here are the old VANOS units:





And the new VANOS units:





Now I am happy to report that the engine is nice and quiet, no more embarrassing tapping/knocking/diesel like noise. Also, no more startup rattle : Top

The problem is that the engine feels slightly ' lumpy '.

The idle is at 600 rpm and is steady. When the accelerator is pressed (car not moving) , there is a slight vibration up to 1200 rpm and then smooths out .

When driving along, at any speed, it feels like you are going over lots of ' bumps ', but the road is smooth.

I connected Carsoft V8.3 and there were no fault codes. I then took it to BMW for diagnostics ......... ........ same result no fault codes.

I tested for vacuum leaks ......... none .

Any ideas anyone?

[memyselfundich]

lumpy Idle can be caused by the Crankshaft Ventilation thingy on the back of the Engine block. I had a fault ignition coil that caused a lumpy reving for weeks before it finally died and showed up on the Faultmeter. Sparkplugs and Lamdba´s also are possible candidates for causing a lumpy idle.

How much did you pay for the whole repair? How much milage does the car have?

Ups sorry, 101miles

[Glacier]

Hi, yes, I think you are reffering to the PCV valve, No.2:

 RealOEM.com BMW E38 740i Intake manifold system

This was replaced about 2 years ago, so not a likely candidate I would have thought. Also, I think you would have got smoke and a wheezing noise if that had gone.

I have put in 8 new coils and spark plugs and 2 aftercat O2 sensors.

I did the repair myself and the timing was 'by the book'.

If you are asking about the price of parts:

2 VANOS units = £250 each.

2 check valves = £10 each.

Valve & upper timing chain gaskets = £50

Timing tools = £300.

Expensive?.............yes!

But worth it just to get shut of that embarrassing noise.

Still no fault codes!

Anymore ideas?

Thanks.

[memyselfundich]

do you have access to a "INPA" enpowered laptop?

if yes, then you could try the "Unruhemessung" Not sure how it´s called in english - It´s the Measurement you can start to see which cylinder is running not a smooth as the others. The Coil´s *can* bei DOA, are they aftermarket or OEM Bmw?

Switching of the After cat sensors is usually not needed - but the BEFORE cat sensors are quite important.

While you are already busy spending money - switch the "LMM" Air Mass measurement things in front of the throttlevalve - which you can also switch out while you are at it Then change the Valve cover gaskets, and your engine will pur as new

[Glacier]

I think you mean 'synchronized' cylinders.

No INPA laptop I'm afraid. Surely BMW DIS would have found something like incorrect timing in the cylinders?

The coils were OEM BMW.

Yes the 'before' cat sensors are important as you say but, I think there would be a fault code if one was broken.

New valve cover gaskets went on.

Again, if the MAF was suspect I would expect a fault code.

But there aren't any : No

Thanks for your input.

[memyselfundich]

you don´t need a fault code for the component for not working as fast / accurate as it could. Might not be enough to pass the threshold for the error to be logged, but still might cause erratic problems... I drove around with that defect coil, and was getting really annoyed with the lumpy ride - and I didn´t have any fault codes either. I just switched the Spark plugs from ngk to bosch and thought the spark plugs where crappy...

What gaskets haven´t you switched yet? Air intake gaskets? Have you resetted the adaption stuff, and driven for 30 or so miles?

[McTube]

Zitat von Glacier

But there aren't any : No

Do not ever overestimate diagnostics. There is a bunch of things it will not see, but an experienced mechanic will....so I agree with the above answers.

[Glacier]

Yes, you are probably right.

The air intake manifold gaskets were done at the same time as the PCV valve, and I checked for vacuum leaks by spraying brake cleaner all around the engine to see if there was a change in the idle........nothing.

When I tried to reset the adaptions there was a message saying "Module not responding". Even so, I have driven about 300 miles since the re-timing so I would have thought the DME would have learned the adaptions by now.

I wonder if there is a burnt valve or something?

Oh well, I'll keep trying to find what's wrong and will report back if I find anything.

Many thanks again for all your suggestions.

[macgyver52]

Hi Glacier,
it looks like i have the same problem with my 740i.
It also has the startup rattle, but i try to ignore it until it gets worse.
The more annoying problem is the vibrating engine in the same rpm range.
Do you or anyone have a solution by now?
I checked nearly everything, but i can´t find the reason.

[Glacier]

Hi Stan,

not sure but, I think the startup rattle is caused by the oil draining from the vanos units, No.1:

 RealOEM.com BMW E38 740i timing gear timing chain top - VANOS

When I changed the the two units I also changed the oil check valves, No.8:

 RealOEM.com BMW E38 740i Cylinder Head Attached Parts

So, I'm not sure if it was the check valves, vanos units or a combination of both that cured the startup rattle. The vanos units change certainly fixed the ticking/tapping diesel-like noise

I did as 'Memyselfundich' suggested and got myself INPA. Here are some live data pictures of the cylinders:













I'm not sure what all that means so, maybe some of you German experts could confirm that they don't look too bad. Or do they seem not to be very well synchronized?

Now.......... I have been doing more investigating and I found that these parts on the nearside rear wheel have some play in them, No.2 & 5:

 RealOEM.com BMW E38 740i REAR AXLE SUPPORT/WHEEL SUSPENSION

When the wheel is rocked at 12 & 6 o'clock there is about 1/4 inch movement. Nothing at 3 & 9 o'clock.

So, I have come to the conclusion that maybe I have been looking in the wrong place all the time! Most probably I did time the engine correctly and, by a crazy coincidence at that exact time, the rear balljoint started to make the car feel lumpy? And that's why I wasn't getting any fault codes from the engine.

Of course this is all guesswork until I have changed the offending parts. I may as well change the other rear bits too and I have got the parts from good old Ebay-de:

 REP SATZ QUERLENKER_HA 7ER E38 KOMPLETT 10-TEILIG NEU! on eBay (end time 14-Mar-11 13:00:40 GMT)

Waiting for this:

 Advanced Keyword Product Search --- Sealey & Draper Tools - CCW-Tools

More expense!

I will report back on my findings.