ML270 CDI 2001 wont start

[MLbrokenagain]

Hi all, i'm new to this forum and could really do with some advice.

My ML270 CDI recently had a problem cold starting would start straight away but then die and would be a pig to start again. Once turning over 2-3 times it would burst into life (once started it was fine). Took it to my local garage, they had a look over said the fuel pump was fine but it did need a new fuel filter and a good system clean. They did this clean, also did a diagnostic check and said there were no faults in the engine so all looked ok. They also checked the one way valve, seals etc. This was about 1 month ago.

The car has been fine, until this morning. This morning it started on the button then died, but this time i could not start it again. RAC came out and just cranked it until the battery went flat. They put some 'easy start' around some pipes and seals and said this would start it. It didn't start.

He put the diagnostic machine on but couldn't get a signal to run a test so said its probably the ECU that's knackered as the car wasn't communicating with his machine.

I'm no expert but i'm not convinced about his ECU theory. I thought if the ECU was faulty then the car would be completely dead and wouldn't even turn over? maybe i'm wrong.

So, it turns over but doesn't start (there is plenty of fuel in the tank)....any ideas? given that its not starting at all could it be the fuel pump?

Also has anyone heard of AA Merctech in Hoddesdon, Herts. I was going to give them a call tomorrow but not dealt with them before (sorry, not sure if i can name names on here!)

 

[MLbrokenagain]

Also i've had no warning lights come up on the dash

 

[MLbrokenagain]

Sorry another also....the MAF was replaced a couple of months ago so i'm guessing its not that. It was Merc one, not a patented part

 

[WG M-B]

With ignition on are you getting all ignition lights on the instrument cluster?

 

[camerafodder]

When diesels wont start, the first place I always look is fuel. In particular air in fuel. I think the fuel lines on the low pressure side may be clear on your engine, see if you can see some bubbles. If you can then the fix will probably be a couple of 'o' rings and/or some new flexible pipe. All easy and cheap to do.

 

[MLbrokenagain]

With ignition on are you getting all ignition lights on the instrument cluster?

Yep all the lights come on as normal and remain on while cranking the engine

 

[MLbrokenagain]

When diesels wont start, the first place I always look is fuel. In particular air in fuel. I think the fuel lines on the low pressure side may be clear on your engine, see if you can see some bubbles. If you can then the fix will probably be a couple of 'o' rings and/or some new flexible pipe. All easy and cheap to do.

Ok a bit more info.....i'm female. I'm a whizz with racehorses but don't do cars! however i am always willing to have a look under the bonnet but need a bit of guidance. I can use a screwdriver, i can take the black main cover off the engine, is this where i will find the clear fuel lines on the low pressure side?

The car will be going to the garage regardless but i would like to have a look if its simple to do

 

[joecash]

you need the services of a decent indy, imho.

 

[WG M-B]

Generally when the ecu's fail on these they will not crank and the engine fan will run full bore. It's strange the call out guy could not communicate with the car. If the fuel runs back on these they can need a strong battery to draw the fuel back up!
You could take the engine covers off to look for air in the pipes for starters.

 

[camerafodder]

Ok a bit more info.....i'm female. I'm a whizz with racehorses but don't do cars! however i am always willing to have a look under the bonnet but need a bit of guidance. I can use a screwdriver, i can take the black main cover off the engine, is this where i will find the clear fuel lines on the low pressure side?

The car will be going to the garage regardless but i would like to have a look if its simple to do

I would do as suggested and get it to a trusted garage if you're not familiar with this type of work as you might end up in muddle. This answer is not based on your sex just your honest answer!

Yes the fuel lines are quite visible on the right side of the engine (looking from the front of the car) near the back. They usually have a heatproof dacron type sleeve that you may have to slide back to see. They are about the width of your little finger and look generally quite snakey!

I'm generally very nervous of horses if that makes you feel any better!

 

[MLbrokenagain]

Generally when the ecu's fail on these they will not crank and the engine fan will run full bore. It's strange the call out guy could not communicate with the car. If the fuel runs back on these they can need a strong battery to draw the fuel back up!
You could take the engine covers off to look for air in the pipes for starters.

Re the ECU, i wasn't convinced about was i told by RAC because everything was still working, including lights on the dash. They still come on now even with a flat battery.

I didn't question this at the time but did he need the ignition on when doing a diagnostic test?, as i dont think he turned the ignition on before testing.

I will unscrew the engine cover and have a quick look.

 

[WG M-B]

Yes the ignition needs to be on

 

[MLbrokenagain]

I would do as suggested and get it to a trusted garage if you're not familiar with this type of work as you might end up in muddle. This answer is not based on your sex just your honest answer!

Yes the fuel lines are quite visible on the right side of the engine (looking from the front of the car) near the back. They usually have a heatproof dacron type sleeve that you may have to slide back to see. They are about the width of your little finger and look generally quite snakey!

I'm generally very nervous of horses if that makes you feel any better!

I will only be looking, if it gets more complicated than undoing a few screws i wont go near it. Its more curiosity, if i see bubbles in the lines then i will be happier knowing its not anything major. If i cant see bubbles, or leaks or anything blindingly obvious then i will pray its just my inexperienced eye and still nothing major!

Men always say to me 'I don't do horses they have four legs and a mind of their own, much safer with motors!'

 

[MLbrokenagain]

Yes the ignition needs to be on

Sometimes i think these recovery companies are only capable of changing a flat tyre and charging a flat battery....or he knew it was going to be a garage job and just wanted to get away quick. Stupid here didnt think to ask the question at the time!

 

[WG M-B]

Where are you based in herts? You may have an indie or good diesel specialist local?

 

[MLbrokenagain]

Thank you for your suggestions. Unfortunately my plan to have a look is short lived as i cannot get the engine covers off as they are fixed with star type screws, not your regular screws and i only have normal screwdrivers. I will just have to hope for the best tomorrow.

 

[MLbrokenagain]

Where are you based in herts? You may have an indie or good diesel specialist local?

Cheshunt / Broxbourne. There is a Merc specialist in Hoddesdon (AA Merctech) i will call them in the morning.

I would take it to my normal garage but they don't generally keep ML parts in stock and although they will fix the car it might be in there a week

 

[jay1983]

Definitely sounds like air in fuel lines. O rings perish over time. Had exactly the same issue on mine when I first got it. Had rings changed by indie and been fine ever since.