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Stan
Stan, Mercedes Technician
Category: Mercedes
Satisfied Customers: 3526
Experience:  Technical support engineer
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Yes i have a 07 plate sprinter that had a new injector in No

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Yes i have a 07 plate sprinter that had a new injector in No 2 fitted in sept by my merc dealer. I took it in again last week 3,000 miles on the clock later for a bad start problem. They diagnosed and fitted a new injector in No 3. £ days later and about 600 miles it has same problem starting and ends up in another merc dealer where they diagnose and fit injectors in No 1, 3 and 4. Then it goes from them in Manchester to Leeds and hits slow traffic and peters out never to start again. It goes back to Manchester by recovery truck having been checked by a merc 24/7 mechanic who says it has no compression. Your thoughts please?
Submitted: 2 years ago.
Category: Mercedes
Expert:  Shantal-Mod replied 2 years ago.
Hello,
I'm Shantal and I'm a moderator for this topic.
I've been working hard to find a Professional to assist you with your question, but sometimes finding the right Professional can take a little longer than expected.
I was checking to see if you had already found your answer or if you still need assistance from one of the Professionals.
Please let me know if you wish to continue waiting or if you would like for us to close your question?
Thank you,
Shantal
Customer: replied 2 years ago.

Hi Shantal,

I havn't got an answer so would like one but if it's going to take this long then i feel i have wasted my money!

Expert:  Stan replied 2 years ago.
Hello,
If the injector replacement solved the poor starting issue, it is hard to doubt that they were not faulty. Faulty injectors could have had bad spray pattern before failing completely, causing detonation and piston meltdown. Of course it is not likely that compression loss at all cylinders at once.
If all cylinders are missing compression, i recomend to have the timing chain checked- it could have streched or broken.
In any case, the compression should be checked once again to determine which cylinders are affected. If compression goes up when oil is added to the cylinders- it means that problem is with piston rings. If not, it is caused by cracked piston, blown headgasket or valve damage.
regards,
Stan
Customer: replied 2 years ago.

Hi Stan,

After this the Head was taken off and it was found the head gasket was blown between 1 and 2 and No 2 piston cracked.

My next question is why?

Expert:  Stan replied 2 years ago.
Bad injectors can cause detonation, which leads to piston damage (melting or cracking of the pistons). The gasket can go out from mileage, overheationg or prolonged overload, but overpressure due to detonation in combustion chamber can contribute to the issue.
My opinion is that old injectors were the root cause.

regards,
Stan
Stan, Mercedes Technician
Category: Mercedes
Satisfied Customers: 3526
Experience: Technical support engineer
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