[mercgtc]

everyone up to now mentions map maf and other sensors but get back to basics diesels need fuel if they get starved they either stall or struggle you say you replaced the fuel filter but did you consider the in tank fuel strainer which is on bottom of priming pump if the screen is blocked /obstructed by any debris or worse diesel bug in tank it can cause these issues - ask me how I know - if the tank has any debris in it the strainer needs cleaned there are products to add into tank but the only true way of achieving it is to remove tank clean and reassemble not an easy or pleasant task but doable if you are used to diy mechanics . the tank sender pump unit needs to be dismantled to get to pump and strainer and if your car is high mileage its worth replacing this electric pump when you have it stripped out consider how many cycles it has gone through in its life you,ll kick yourself if you dont then have it fail not long after removing tank etc - again ask me how I know - any way clean the fuel side first then start looking else where if there is no improvement but I bet there is .