More vibrations

[bullocka]

Hello,

My '99 SL320 auto started to vibrate when stationary in park, neutral or drive. When in park or neutral, the engine seems to be hunting a bit (the tach needle moves up and down slightly) and the car physically shakes from time to time. When stationary in drive, the vibration can be felt through the brake pedal and through the steering wheel.

Maybe I own a diesel version (!!), but it never used to do this. Had the mounts changed by AMC London - genuine MB parts and just had the plugs changed along with a B service. No change and nothing showing up on the diagnostics. The only other thing I've done is to put some cleaner in the fuel to see if an injector might be blocked.

Two additional things have been mentioned; coil pack (but I am told that would light up on the dash) and a throttle return actuator. Hmm.

Anyone have any ideas?

 

[television]

All I can think of is to have the spray Pattern of the injectors checked. The only other thing is the MAF filter.

 

[bullocka]

Thanks. Someone mentioned that in addition to the plugs, I should try replacing the plug leads. Does that make sense?

Andrew

 

[BlackC55]

You have a missfire by the sounbds of things.

Check coils, leads etc.

 

[television]

You have a missfire by the sounbds of things.

Check coils, leads etc.

This is what I cant get my head around, these things break down more under load than at idle, unless the unused part of the voltage is is breaking down in a coil pack.

The high voltage EHT in a TV can leak and arc when at low brightness level, but not leak at the brighter level as this voltage is being creamed off, same in a coil pack really.

Makes sense

 

[bullocka]

Thanks for the advice all,

The car seems to run perfectly with no obvious problem on the move - just at idle or at a very slow crawl when it's all shake rattle and roll. Well, the engine definitely is hunting and the tach needle moves up and down slightly (in neutral). It's a pain because, living in London I'm always stationary! So based on what you guys suggest, I'll get the coils and the leads changed.

If you think of anything else I should investigate, please shout.

Cheers,
Andrew

 

[television]

Thanks for the advice all,

The car seems to run perfectly with no obvious problem on the move - just at idle or at a very slow crawl when it's all shake rattle and roll. Well, the engine definitely is hunting and the tach needle moves up and down slightly (in neutral). It's a pain because, living in London I'm always stationary! So based on what you guys suggest, I'll get the coils and the leads changed.

If you think of anything else I should investigate, please shout.

Cheers,
Andrew

You only need to buy one, and move it around, you could also check the colour of the spark on each plug, it will only be one pack with luck

 

[bullocka]

Great - thanks.

Just had a call from my garage saying it would need 12 leads @ £20 each and 6 packs (I think), totalling £1,100 including labour. Anyone know a decent garage in London (preferably SW or W) that might be able to help with this problem?

Andrew

 

[BlackC55]

I can reduce this price ALOT.

Give me a call and I can do it while you wait.

 

[bullocka]

Fantastic! I could do with a trip to the south coast. Who should I ask for when I call?

Thanks a lot for getting back to me.

Andrew