[Sanidhya mukund]

W204 C-class sluggish when accelerating. Could E20 petrol be the cause?

Hello all,

I am creating this post to seek your views about a problem I’m facing with my 2014 W204 C200 CGI.

I bought this car new a decade ago and have been maintaining it at the authorised MB dealership since. It has covered about 46K kilometers at the time of writing this. The transmission fluid has been changed timely and the oil and filter changes have also been adhered to.

Off late, I’m noticing the following symptoms:

When I’m on the highway doing 70-80 KM/h, and I accelerate from this speed to overtake another car, I notice a jerk/lag/sluggishness. The best way to describe it would be that whenever I suddenly accelerate, the car doesn’t pick up like it used to. It feels like it loses power for a few seconds.

There is no check engine light glowing. The OBD scan doesn’t return any findings.

A few suspects could be:

1. The spark plugs: Given the low running, the MB service advisor asked me to put it off for later because according to him, they can last much longer than 45K kilometers.

2. Fuel injector nozzles: The maintenance schedule specifies that they have to be serviced at a certain age and mileage. However, the MB guy told me not to bother, again, because of the low running.

3. Air filter hose pipe: there is a slight crack in the air filter intake pipe. I suspect it occurred when the front end was dismantled to change the radiator fan assembly at the dealership about a year ago. They told me not to worry about it and patched it with “cotton tape”:





4. Lastly, could it be that its E20 petrol slowly administering death to the car? I only fill up XP95 and that too at a reliable outlet near my place.


Would really appreciate your views on what could be the issue here.

[Shreyans_Jain]

Originally Posted by Sanidhya mukund

W204 C-class sluggish when accelerating. Could E20 petrol be the cause?

Hello all,

I am creating this post to seek your views about a problem I’m facing with my 2014 W204 C200 CGI.


4. Lastly, could it be that its E20 petrol slowly administering death to the car? I only fill up XP95 and that too at a reliable outlet near my place.


Would really appreciate your views on what could be the issue here.

While each individual point that you list can potentially be the cause, somewhere, the problem is interconnected.

XP95 is E14, which if the car is not rated for will corrode your pumps, injectors and spark plugs. Sad part is that there is nothing you can do about it. You’ll burn money to replace the parts, and then watch them fail again.

[Jeroen]

Couple of thoughts:

Yes, spark plugs should last longer, but he should have pulled them out to verify their condition at least!

That cracked inlet pipe. As long is the crack is before the mass air flow meter it normally isn’t a huge problem. But even so, the crack will allow warm air surrounding the engine to be drawn air, rather than cool air from the outside. But it will have to be a large crack before you would start noticing it in degrading of engine performance.

I would check the air filter and the air intake. A dirty air filter or any obstruction in the air inlet circuit will lead to engine performance degradation quickly.

As no error codes are shown, another thing you might want to try is cleaning of the air mass meter. Make sure to use proper air mass metering cleaning fluid. Not brake fluid or so.

Good luck

Jeroen

[Gansan]

Originally Posted by Shreyans_Jain

While each individual point that you list can potentially be the cause, somewhere, the problem is interconnected.

XP95 is E14

Can you please mention the ethanol content of other petrol brands such as Speed, Power etc too?

[Shreyans_Jain]

Originally Posted by Gansan

Can you please mention the ethanol content of other petrol brands such as Speed, Power etc too?

All varieties of petrol are 14 and 15% blends here in Delhi NCR nowadays.

[Maverick Avi]

E20 fuel can definitely be a reason for poor pickup. I mistakenly filled up tank full of E20 petrol at an IOC outlet in my 2019 Wagon R in Delhi and could instantly feel loss in power. Once the petrol got consumed I filled up regular petrol at HP outlet and could feel that the power and pull was much better.

My personal opinion and observation is that most IOC outlets in Delhi sell higher ethanol blend of petrol. I am not sure of the percentage mix but can definitely feel the difference so am sticking to HP outlets for now. You can try a HP outlet in Delhi to fill petrol in your car and see if it makes any difference.

[Aditya]

Mercedes C-Class (W204) sluggish while accelerating | Could E20 petrol be the cause? Posts moved to a new thread.

[Aviator_guy]

Originally Posted by Maverick Avi

E20 fuel can definitely be a reason for poor pickup. I mistakenly filled up tank full of E20 petrol at an IOC outlet in my 2019 Wagon R in Delhi and could instantly feel loss in power. Once the petrol got consumed I filled up regular petrol at HP outlet and could feel that the power and pull was much better.

My personal opinion and observation is that most IOC outlets in Delhi sell higher ethanol blend of petrol. I am not sure of the percentage mix but can definitely feel the difference so am sticking to HP outlets for now. You can try a HP outlet in Delhi to fill petrol in your car and see if it makes any difference.

How do you differentiate between a dispenser of E20 vs regular fuel? Do the petrol stations have different pumps/dispenser? Here in Blr, I haven't noticed anything different at the pumps (they have dispenser for regular fuel and another for premium high octane). If possible, do share picture of the pump/nozzle dispensing E20 fuel.

[Beemer1077]

There is a chance about the kind of fuel you put in. If possible, try to put high octane fuel for once and see how things are. Merc engines are notably reliable enough, and probably that E20 fuel could be a reason.

[Maverick Avi]

Originally Posted by Aviator_guy

How do you differentiate between a dispenser of E20 vs regular fuel? Do the petrol stations have different pumps/dispenser? Here in Blr, I haven't noticed anything different at the pumps (they have dispenser for regular fuel and another for premium high octane). If possible, do share picture of the pump/nozzle dispensing E20 fuel.

This IOC pump I am referring to has E20 written on the vending machine pretty clearly and in bold. I managed to overlook it initially and realised it once the tank was filled up. Sorry, don't have a picture of it but it cannot be missed easily.

[Aviator_guy]

Originally Posted by Maverick Avi

This IOC pump I am referring to has E20 written on the vending machine pretty clearly and in bold. I managed to overlook it initially and realised it once the tank was filled up. Sorry, don't have a picture of it but it cannot be missed easily.

Thank you. Is E20 fuel priced differently than normal fuel ? If not, then why would one want to fill E20 (other than by mistake). I'd imagine there would be incentive to fill E20 fuel (lower price).

[lapis_lazuli]

Originally Posted by Sanidhya mukund

W204 C-class sluggish when accelerating. Could E20 petrol be the cause?

Hello all,

I am creating this post to seek your views about a problem I’m facing with my 2014 W204 C200 CGI.
.

Hi can you not try once filling a tank of XP100 which is not blended and see if it made a difference? Just wondering.

[Sanidhya mukund]

Originally Posted by Beemer1077

There is a chance about the kind of fuel you put in. If possible, try to put high octane fuel for once and see how things are. Merc engines are notably reliable enough, and probably that E20 fuel could be a reason.

Thank you for the reply!
I have been using XP95, which is 95 Octane. (The recommended grade for this car).

Originally Posted by Aviator_guy

Thank you. Is E20 fuel priced differently than normal fuel ? If not, then why would one want to fill E20 (other than by mistake). I'd imagine there would be incentive to fill E20 fuel (lower price).

The problem is, ethanol blended fuel is the only available option at some places now. As D-Bhpian Shreyans Jain said above, XP95 cannot be had without 14% ethanol blending.

Originally Posted by lapis_lazuli

Hi can you not try once filling a tank of XP100 which is not blended and see if it made a difference? Just wondering.

Thank you for the suggestion! I could try that, but would that not cause knocking? Suppose I already have some 95 octane in the tank and it mixes with 100 octane that I put in. Will that not lead to a grade of fuel that the car is not designed to run on? I have limited understanding on this so please correct me if the above presumption is incorrect.

[Beemer1077]

Originally Posted by Sanidhya mukund

Thank you for the reply!
I have been using XP95, which is 95 Octane. (The recommended grade for this car).

If possible, try from a different fuel station such as BP, HP, or something like Shell. It is possible to get different outputs, mostly because each brand has different additives for high octane fuel, so probably there will be a noticeable difference. Try that, maybe you will understand which will be suitable. While XP95 is recommended, try Speed97 from BPCL or Power100 from HPCL - you may get to see some difference.

[lapis_lazuli]

Originally Posted by Sanidhya mukund

Thank you for the reply!
I have been using XP95, which is 95 Octane. (The recommended grade for this car).

Will that not lead to a grade of fuel that the car is not designed to run on? I have limited understanding on this so please correct me if the above presumption is incorrect.

Honestly I dont have a scientific answer but higher octane should cause no knocking. I used to mix normal petrol and high octane in 50 50 ratio to "arrive" at an intermediate higher octane, as solely on high octane was expensive and the car used to be too eager to lurch forward which was a problem in Ghaziabad traffic. Residual ethanol would be minimal I would tend to think. You may do the experiment.