[s.m.]

Ml 430 acceleration problem

Hello,i am new here,but i can see that there is a lot of people that are expert in problems as mine
I have ml 430 and Ml270 cdi
The problem with ml 430 is acceleration,on highway up to 80 mph ml270 cdi is going the same,i mean is this posible,that 430 vs 270 cdi is the same acceleration,what is wrong with my car?,thanks

 

[FAR888]

Hello,i am new here,but i can see that there is a lot of people that are expert in problems as mine
I have ml 430 and Ml270 cdi
The problem with ml 430 is acceleration,on highway up to 80 mph ml270 cdi is going the same,i mean is this posible,that 430 vs 270 cdi is the same acceleration,what is wrong with my car?,thanks

Welcome to the Forum!

You really should fill in your profile to include where you are and the year and model of your truck - A lot of Members can only help you if they know that.

You problem seems to be that your ML430 (which should be faster than your ML270 CDI) is not performing at it's best.

There are a number of reasons for it's sluggishness which I am sure the more knowledgeable members of this Forum will chip in with soon.

From my novice point of view it could be:

Plugs
Mass Air Flow Sensor
Fuel Pump
Fuel Filter
Catalytic Converters clogged
Oxygen Sensors

Good luck!:thumbsup:

 

[s.m.]

thanks for the tips,i will do that

I think maybe it could be MAF,how can i check it,do i have to go to service to check it?
Thanks

 

[FAR888]

thanks for the tips,i will do that

I think maybe it could be MAF,how can i check it,do i have to go to service to check it?
Thanks

If you have an OBDII scanner you can hook it up to the truck and check the codes yourself.

Failing that, you could go to a carshop or mechanic that have an OBDII scanner to check the codes for you.

Make a note of any stored codes and then report back to the Forum.

 

[s.m.]

i will do that,thank you

 

[Mac]

Google says the ML270 has 272.9 ft.lbs at 1600 rpm. Our ML430 was 288 but not until 3K rpm. If you want good hill performance, you've got to gear the 430 down to 4TH and get the rpm over 4K in the ML430 to get the 430's 2-stage intake manifold working for you.

You're thinking: but the gas mileage! That's true in my case. Overall, the 430 got about 1-2 more mpg on a 600 mile drive. However, on my daily drive, I actually get better freeway mileage in our ML500 than I got with the ML430--because of a steep grade on the way to work. With the 500's 339 ft. lbs. of torque, it takes the same hill in 5TH on cruise control, at over 70 mph, at just 2700 rpm.

I am not experienced with diesels. I am sure there must be trade-offs, e.g., with the ML430, from a standing start at the foot of an uphill freeway onramp, you probably could merge onto an freeway at 60 mph (in third gear) in a much shorter distance than the ML270.