How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Matt Your Own Question
Matt, Mechanical Engineer
Category: Mercedes
Satisfied Customers: 22766
Experience:  BEng hons Mech engineering, in auto industry 22 years
Type Your Mercedes Question Here...
Matt is online now

, I have a 2007 315CDI, last six months or so the

Customer Question

Hi, I have a 2007 315CDI, for the last six months or so the van has no power, it will go up to 3000rpm or build up to 45 to 50mph but that's it. Overtaking is impossible etc. Garage
replaced air flow meter, 4 injectors, regenerated PDF and accelerator pedal at a cost of about €2k and still the problem persists. Any help welcome. Thank you
Submitted: 3 years ago.
Category: Mercedes
Expert:  Matt replied 3 years ago.

1st consider changing the fuel filter as if this partially blocked this will reduce pressure at the main pump

If OK then also check the connections to the EGR valve, if either the vacuum pipe of electrical connection are damaged / corroded then the EGR can be on all time which certainly will hurt performance. Its also possible that its a fault with the EGR valve so its worth removing the valve and cleaning it out with brake cleaner, if it looks particularly clogged then replace it.

If this is OK then check the small vacuum lines to the turbo and its connected control solenoid on the bulkhead, any cracks or leaks can give turbo issues and its best to have the boost pressure measured actually measured with a boost gauge to check that the turbo is healthy and that the sensor is reading correctly

If its a variable vane turbo (they’ll be an actuator on the turbo body - but not a wastegate) then check its vacuum pipework as above and check the connections to the diaphragm / solenoid valve

Also worth checking that the glow-plug relay is switching off as they can stick on and leave the glow plugs also on - on some cars this can force it into limp home

Expert:  Matt replied 3 years ago.

do you still need help with this ?
Customer: replied 3 years ago.

Hi, unfortunately we are very busy and are only getting to the sprinter tomorrow, I will keep you informed. Thanks

Expert:  Matt replied 3 years ago.
No problem Paul

just get back to me on this post