tebalto

Do you feel the 3200cc Cdi engine lag response when stepping hard on the gas pedal?

Is it a turbo lag or what? It seems like the engine response is a bit out of sync with what my right foot is doing!
Is it fixable with some software upgrades or a technical assistance?

Thank you.
Regards tebalto

DavidNJ

Significant turbo lag has been reported by several people who have driven/test driven it, including myself. It seems to be part of the design.

Can it be reduced? Good question!!! My guess is not or it would have been done already. CDI is new in US, not elsewhere.

glojo

I understand your question, and I think we have discussed your problem. Am I correct in saying that you are of the opinion that your new 211 does not accelerate as fast as your previous E270CDI???

The 270 is a 5 cylinder inline engine compared to the 320 6 cylinder inline. There should be no difference in the workings of both engines fuel injection, turbo charger etc. I have no knowledge of the electronic management that controls both engines but would presume they are similar.

Was your 270 the older 210 model E-class? If so there should be a marked improvement in performance.

I am positive that on all performance tests the 320CDI out performed its 320 petrol counterpart. Surprisingly the diesel is quieter than the petrol engine apart from tickover. (the diesel is a whole two decibels louder) Some folks equate the roar of the engine directly to performance so the deisel is at a disadvantage. The newer 211 320CDI is also quicker than the older 210 equivalent. If there is indeed some form of turbo lag, then it would show up on acceleration tests and it would make the results even more amazing if the CDI had to wait for the turbo to cut in, and still manage to out perform the 320 petrol????

I feel frustrated that I cannot offer constructive advice because I believe that you have already had a further test drive in a different 320CDI with a similar result to your own vehicle.

The only thing I can think of is perhaps you have the gearbox in ' C ' mode. This would certainly give you the symptoms that you are experiencing. Failing that do you and each of your passengers weigh in excess of 180kg each??

I hope you resolve the problem to your satisfaction.

Regards,
John
Sunny Torquay

ssafran

I experienced something very simiilar when I test drove the car. I thought it felt almost as if the engine cut out for a millisecond at times before picking up. When you combine that with the out of sync brake feel the whole car felt to me like a foreign film where the lips don't match the words. Now I'm sure about the brake feel being off but I'd believe that the tuning or computer or something on the test car I drove could have been off as far as acceleration is concerned. Too many other people have reported on the braking problem for me to belive that that was an individual vehicle flaw.

Otto

you have to know how diesel engine works

gas engine can response quickly and ignite the fuel with air even it does not reach the compression ratio via spark plugs -- as long as you don't care to pay money on gas for gaining speed. while diesel engine has no choice to wait for reaching the compression ratio before igniting the fuel with air.

if you want to have a performance car, get a gasline engine; if you want to save money on fuel, get a diesel engine. (this is why there is no mb amg or bmw m models use diesel engines.)

glojo

You are correct in so far as there is not an AMG diesel at present. However you appear to have no knowledge whatsover of how a common rail direct injection diesel engine operates.

The 1800 VW GTi is now being beaten by the equivalent 1800 diesel in motor racing. Tiffiney Dell raced against Jensen Button, Dell was driving a 3ltr diesel BMW and Button the 3ltr petrol. Button won the race by just under a cars length. If the race had been over a longer distance the diesel would have easily won because of its fuel economy.

Your conclusions are at best very third world, we used to have sluggish, smelly smoke emitting diesels, but thanks to diesel research and modern fuels, those days have long since past.

The 'S' type Jaguar, Mercedes-Benz, BMW and Volkswagen have excellent common rail direct injection diesel engines that put the petrol equivalent to shame. The E400CDI is an extremely impressive vehicle which I am sure would give the E500 a good run for its money.

I am sorry to have taken 'your bait' but your remarks about diesel engines belong back in the 20th century.

John

Silver_Lana

You are both wrong.
There is a C30 CDI AMG vehicle.

Link to C320 CDI AMG

Who says diesel and performance can't mix?

DavidNJ

Let throw my $.02 in.

Diesels are more efficient because they have fewer pumping losses. Spark ignition engines use a throttle restriction to reduce power. Reducing air and fuel in the same ratio. Diesels use less fuel. The lower engine speeds also allow things like softer valve springs.

Higher compression may also help, especially with CDI. However, traditionally, diesels have had less precise combustion timing which hurt them.

Diesel fuel also has more energy than gas. This contributes to less fuel used per unit of work produced. But not an increase in efficiency (which would be more work produced per unit of energy used).

There is nothing to prevent diesels from making more power than gas engines. And, IMHO, with in 10 years or so the overwhelming majority of new cars will be diesel/electric hybrids. At that time, a E-class car will produce 6 second or better 0-60 with city and highway mileage of around 40-50 mpg, maybe a little better if car weights drop from lighter materials.

jyg e500 maybe

was no lag, it was like a 60.s muscle car,threw me back into seat.

glojo

Never let it be said that I am not man enough to admit a 'slight' error Thank you very much indeed for posting the very informative link.

So just to clarify my previous post. "There are no diesel AMG vehicles available YET in the UK".

Regards,
John
Sunny, hot Torquay

Silver_Lana

And a very fine Man you are to admit errors!
I figured a car like the C30 AMG would have made it over to the UK by now.
You always have welcome insight to the forums on here. Just wanted to point out one of many new and upcoming exceptions to the Diesel/No Performance rule.

Cheers,
Opie
From a Sunny and Windy Franklin Lakes

Otto

yes, Silver_Lana is right but this model is not available in US.
(there is a amg c32 in US)

another fact is the weight of diesel engine (320 cdi) is around 200 pounds heavier than the weight of gasline engine which means your car always carrys a 200 pounds football star that is why those lead footers are unhappy the performance of diesel engine. (diesel cars won in the motor racing is not a problem because they do well after cars have had speed -- the problem is how soon to reach 0-60 mph -- 320 CDI claims that 6.8 seconds, 0.3 of a second faster than the gasoline engine is NOT true, you can test it by yourself, I think 7.7 seconds is about right. I wonder how 6.8 seconds (0-60 mph) comes out.

by the way, even beating your sister, e320 gas engine, does not mean 320 cdi perform well because the e320 3 valves design gasoline engine is NO good anyway, it can be easily beaten by bmw 530. (the higher price of diesel model only means there are few buyers and manufacturing cost is higher -- does not mean it is better.)

fuel efficiency wise, diesel engine is better than gasoline one.

glojo

Hi Tebalto,
I would like to apologise for getting involved in the 'off topic' discussion about diesel engines.

You have asked a very good question and unfortunately have not had much response.

Those of us that have this engine just laugh at some of the responses that have appeared on this thread they seem to be coming from genuine people who sadly do not realise the quantum leap these advanced engines have made.

I can only recall one person complaining about poor acceleration with his 320CDI, and its' cause was a 'sticky' kickdown switch, which I believe (I stand to be corrected) is located underneath the throttle pedal. Once this problem was rectified the vehicle performed as it should have.

Could you possibly explain this 'throttle lag' sensation? How does it equate to your previous 270CDI?

I think some contributors do not realise that you are comparing the 320CDI to the 270CDI. Both of which are diesel engines!!!

Fingers crossed that someone, somewhere can offer some constructive advice.

John
Sweltering hot
Torquay

DavidNJ

The turbo diesel has a...turbo...which has to spool up. Generally this is better than a gas engine, because the diesel never has the throttle restriction.

However, if the diesel is cruising at 1400 rpm, and you floor it, the lag will be there. Because the turbo diesel is probably generating a high boost, it would be more pronouced.

Zero-to-60 runs are made with the engine already reving against the torque converter and brakes. So the turbo is spooled up and it launches in the torque peak. Car and Driver does a 5-60 run, which they didn't report, to avoid the hard launch bias.

glojo

Hi David
I bow to your knowledge here because I am trying to picture revving the engine in gear with your foot on the brake??????

You obviously realise that the 320CDI ONLY comes with an automatic gearbox??? There is NO manual gearbox option.

Could you please explain to me how you do this without causing long term damage to the vehicle?

Thanks for the interesting post

John
still swelteringly hot
Torquay

jyg e500 maybe

if you are a entrance ramp on highway and you floor it, THERE IS a slight delay , then i the power comes in like gang buster, Also 0-60 and quarter mile cdi is faster than e320. accoring to road & track,last issue firt drives,

DavidNJ

Drag racing, the driving part, is about the first 60 feet. After that it really up to the car.

Automatic transmission have a fluid coupling with internal vaning that multiplies torque. They are called torque converters. Below a certain speed, they don't transmit power. On a street car that is around idle (900 rpm). On a drag race car that is higher...2500, 3000, even 4000 rpm.

The brakes on you car are much more powerful than the engine. Virtually any car with good tires can average close to 1g average deceleration from 60 mph. Average acceleration for the cars we are talking about is about .4g to 60 mph.

To launch an automatic, we hold the car with the brake and rev the motor to the low end of the power band. The torque converter is slipping and heating up. It is also mutlipling the torque like an extra gear. When you release the brake the car jumps off the line. The ideal amount of revs and throttle opening is dependent on the cars weight, power, and traction, which can vary by track and weather conditions. You want to get the most power to the ground (some wheel spin) without excessive wheelspin (transmitting little power to the ground). Drag racers spend all day perfecting this.

With a manual the process is similar. Except that here you disengage the engine with the clutch. You rev the engine in to the low end of the powerband. And typically you dump the clutch. On an S2000, you dump the clutch between 6000 and 7000 rpm.

To reduce the chance of driveline damage, BMW has started installing a valve which limits the speed the clutch engages when you dump it. Some aftermarket companies disable the valve.

Launch control interrupts the fuel flow (on catalyst cars) randomly to hold the engine to a predetermined engine speed at wide open throttle (WOT). Then when you drop the clutch it continues the fuel interruption to maintain the desired amount of wheel spin. It makes the whole launch very simple. A related feature uses the fuel interruption to reduce revs on a WOT shift.

On a turbocharged gas engine, the launch control allows the turbo to spin without a throttle restriction. On a Supra TwinTurbo, it can be worth over 1 second in quarter mile times with no other changes.

johna1

All very well in theory, but in practice MB have fitted a safety lock to the E Class that cuts power completely for about 5 seconds if the accelerator and brake are simultaneously pressed.

I imagine this is to avoid Audi type unintended acceleration lawsuits in the US.

If you drive using left footed braking (as I often do), then you need to be very careful about only doing one thing at once, or you have to wait before you have any power again.

It is only through the fly by wire technology that this kind of trick can be easily done.

DavidNJ

I only left foot brake in my race car...