Strange Problem

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Sanj

Active Member
Joined
Jun 22, 2003
Messages
125
Location
Hampshire
Car
BMW M4 Competition pack & C205 250D AMG line
Hmm ...Im wondering if anyone can help me here ...

A few days ago my I went to start up my car ....it didnt start , so I tried agaiin then it was ok .. so I thought nothing of it

However today its got worse ....whenever I try to start the car up from cold it sounds as if the engine is struggulling to fire....although it does start up eventually ...when I try again it fires up straight away

any ideas ?
 
Yes actually i do ...I was parked in my folks driveway which is on a slight tilt ...could this be causing it somehow ?
 
Originally posted by Sp!ke
You don't park on a hill do you?

I think it all depends which way on the hill you park? If it's pointing upwards the petrol could be running back towards the tank,hence poor starting.Maybe the fuel pump is struggling to get the fuel through cus of the way the car is pointing.Failing that "sorry dont know". Apart from park the other way so the petrol runs towards the engine.
 
Im parked so that the petrol runs towards the engine and still get problems.
 
Ive just been scouring the haynes bible,there is a few things to look for worn 1 - battery discharged 2- dodgy battery connections
3 - worn plugs 4 - fuel or ingnition fault 5 - low cylinder compression ( a thought on this number 5, hows your cylinder head gasket any leaks detected)?
 
Originally posted by Sanj
Hmm ...Im wondering if anyone can help me here ...

A few days ago my I went to start up my car ....it didnt start , so I tried agaiin then it was ok .. so I thought nothing of it

However today its got worse ....whenever I try to start the car up from cold it sounds as if the engine is struggulling to fire....although it does start up eventually ...when I try again it fires up straight away

any ideas ?

I had this on my 240 as well . There is a workshop ammendment about this. The dealer used a special greese as per MB on starter motor . Ive forgotten the proper name , but , its the bit that engages. Cost abouat £40 but the engine start was sweet from then on . Seems like its a common thing
 
Fuzzer ,

Is this something I could do ?

apply grease to the starter motor ,

I dont know alot when it comes to engines though !

if i did it at a private garage would that be ok ?

or would the dealer have to do it ?
 
Ive got no idea to be honnest with you. I just let the dealer do it as i don't know about engines etc. I was quite doubtful about it as many people on here will also be after reading my post. But .. whatever they did sorted it.

I would try a dealer...
 
Starting problems are common

Do you crank the car as soon as you turn the key or do you wait for the fuel pump to finish flooding the injectors/carb? Usually, on cold mornings, it is best to let the fuel pump finish spooling before cranking the car.

You can do this by turning the key to pre-ignition stage, listen to the fuel pump (a soft murmer or whining sound) and wait until it stops. Then, crank the engine.

If that doesn't work, wait until the car is cold again and then turn the key to A/C, then press the gas pedal down to its end (slowely) then release it, then turn the key to pre-ignition, wait until the fuel pump finishes spooling, then crank the car.

If either of these two solutions work, you have a weak fuel pump, dirty fuel filter, clogged fuel lines or all of the above. To fix that, buy a quality fuel injector and fuel line cleaner (additives that go with your gas) and that should fix it.

If those two solutions don't work, you're problem is elsewhere. Besides the other problems already mentioned elsewhere, I always suspect either the spark plugs (when was the last time you changed them) and the HT leads. If you haven't changed the plugs for a while, replace them. If you have, check the HT leads. Pull them off the plugs and with a long, dry brush or lint-free towel clean up the heads (the metal parts that connet to the spark plugs).

If that doesn't work, then it has to be something deeper. If you have no mechanical inclination, take to a stearlership. But I don't think it is that serious, especially since the car comes to life on the second time you crank it. I really do think its something with the fuel system, so try out those two simple tests and tell us what you found.

Hope this helps.
 
Originally posted by Hellme

Do you crank the car as soon as you turn the key or do you wait for the fuel pump to finish flooding the injectors/carb? Usually, on cold mornings, it is best to let the fuel pump finish spooling before cranking the car.

Since Ive been having problems Ive been waiting for the fuel pumps to flood the engine.

however its made no difference.


If that doesn't work, wait until the car is cold again and then turn the key to A/C, then press the gas pedal down to its end (slowely) then release it, then turn the key to pre-ignition, wait until the fuel pump finishes spooling, then crank the car.

Ive tried this and it does make a significant difference but doesnt eliminate the problem completely !
for example I still have to wait around 10 seconds instead of 20 !

One thing that I did do is change to optimax then back to regular unleaded a few times ....I was trying to see if it made a difference
ie power, fuel consumption .
but when I did change I let the fuel tank run dry (yellow light) making sure I didnt mix optimax with standard unleaded.

could this have messed the fuel pump in any way ?

Only bought the car in the last 3 months (c 240) the spark plugs have never been changed and the car is 4 years old.

Are the HT leads fully visible as I cant see them ? ....yes I am an end-user when it comes to these things lol !
 
greasing the starter would maybe be beneficial if it was sticking but when they stick its usually when their warm.If engine wont turn over try tapping starter body with metal rod or similar and if it then turns then its a sticking starter mech. This is a common problem on Fords but suppose could happen on mercs too. Is the engine turning over normally but not firing or is it struggling to even turn over ??
 
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I had similar problems

I have a 190E and I had similar problems when I got my car.

From your description, I'd suggest getting new spark plugs, and spark plug wrench (you need a 10mm plug wrench) with a moderately long neck (don't buy a wrench with a super-long or super short wrench) and a feeler gauge. There are 4 wires connected to the plugs - you can't really miss them. Gently pull those wires to reveal the plugs. Those wires are the HT leads. Once you've pulled them out, you'll see a long metal end - check that it isn't rusted, and that no salt residue is stuck to its inside. Give it a good wipe. Then, use the spark wrench and unscrew the spark plug. I don't know what the spark gap for your car needs to be - someone here will be able to tell you or check a website or something. Use the feeler gauge to make sure the spark gap on the spark plug is properly set. Then, screw in the new spark plug using the wrench - just make sure you keep your hand as steady as possible and that the spark wrench is as perpindicular as possible to the engine.

Tell me if you need any more help with this.
 
when you put plugs back in be EXTRA carefull they go in straight, if you cross thread its bad news. If you know nothing about cars you must know someone who's slightly competent and could check plugs etc for you.
 
Sanj,

The plugs are a bxxxxxd to replace on the V6, this is a twin spark engine hence 12 plugs!!

The plug leads are very short as the coils are very close to the cylinders (one for each cylinder)

A Benz Stealer will charge you about £250 alone to change the plugs on top of any service!!

George Fraser changed mine at the last "A" service and I paid £250ish for both the service and plug change amongst a few other small bits and bobs...

You'll notice a vast difference if you change the plugs.... I did...

Good luck!!!
 
I echo Wheelie's comments. The spark plug change on the 240/280 V6 is a real swine. I've been told (by George Fraser) that changing them isn't really a job for the casual DIY'er and that in terms of labour the dealerships usually put aside 1.5 to 2 hrs purely for a spark plug change on these engines. Apparently one bank of 6 plugs isn't that bad but the other bank of 6 require a contortionist with the hands of an eight year old kid.

S.
 
I think replacing the spark plugs sounds like a bit of a nightmare Ill leave it to the dealership if it comes to that....Ive booked my car in for next wednesday...will see what happens....

will let u know.:confused:
 
Originally posted by GDC200
Rirhill can confirm but I think Royale Engineering changed his for about £58 all in!

Maybe it's more accessible on the E.
 
If your car has not had new plugs after 4 years its probably due for them. Mine were replaced after 48,000 and starting was much better. But don't try and do it yourself unless your very sure of your mechanical abilities. They are small 10mm plugs (12 of them…) down a deep hole and VERY easy to cross thread… very expensive if you strip a thread! I'm with the other guys - go to a specialist.
 
Here is a tip for anybody who wants to try changing their spark plugs.

If after unscrewing the spark plugs, you cant remove them from the holes, use a small piece of flexible tubing such as you would use for home brewing:D , this needs to be the correct size to fit snugly over the 'nipple' end of the plugs. Push the tube on and extract the spark plug.

The same method can be used to insert new plugs, start screwing them into the thread using the tubing and there is no way you can exert enough pressure to damage the threads if you do happen to cross thread the plug!

Also helps prevent you burning your fingers if the plugs are hot.;)

I would recommend changing the plugs at least every year, I have seen plugs corroded into the head of a Mondeo, not a nice sight!!
 

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