Honda Civic Rebirth taking more time to reach to 100 km/h

[adnanofpk]

I have honda civic rebirth 2013 vti oriel prosmatic. Every thing is in perfect condition. I have replaced the spark plugs, new coils. changed fuel filter and fuel pump. clean the injectors. Engine is in perfect condition. Its mileage is 1 lack and I am using 5w 30 oil. catalytic has been removed by previous owner and its has plates instead of grill. It zero to 100 time is 13 to 13.5 seconds. I don't know why it is taking that much time. Need your suggestion to reduce that time.
can it be due to no catalytic converter? I have search a lot on internet and people are saying that without catalytic converter car acceleration is much better.

[umairjamil6]

Is it a manual? How do you accelerate when going to 100?

[adnanofpk]

It is prosmatic. i tried with both manual shifting i.e. D1, D2 (shift the gear before it touch the red line) and also by simply set D3 gear but in both cases the results are same and it can not achieve 100 km/h speed before 13 seconds.

[anarkaliantiques]

Spark plugs , throttle , catalytic and fuel filter, valve clearence, if one or more of these are bad that results in poor performance. If none of these are serviced get them all done its usually a 4-5k service from a decent tuning facility.

[muhammad.talha3001]

Most likely the removal of the cat is the culprit. Do you have a check engine light? I remember reading up a similar article 2 years ago on this forum about a person that had a similar problem, and someone replied that when you remove the cat you're supposed to make modifications to turn off the check engine light. Basically, when you remove the cat without making this modification, your engine runs in a kind of "safe mode" all the time where it thinks that the quality of the fuel is terrible. Therefore, to try to prevent this bad fuel from harming it, it goes into a state where the performance decreases and the car consumes more fuel.

[adnanofpk]

No check engine light and the fuel average is very good. it is 9 to 11 in city and in long it gives 15/16 km/l.

[adnanofpk]

All of these things are done. kuch samaj nahi aa rahi reason ka.

[anarkaliantiques]

Removing cat is not ideal, most ustaads don’t like it and remove it because its one less purza to worry about they basically hate the ECU so they make sure its crippled, so it always come back to them. You need a new technician more than the repair itself. Get it back to factory specs and reset ECU once and do the idle relearn it will have to set the tps and other sensors automatically , the air fuel mixture needs to be set by the computer.

[htb456]

Removing the cat is impacting the performance here

[anarkaliantiques]

They also sell the cat-litter so to speak, its one of their deharis as precious metal is inside and the unsuspecting customer will leave it as its just silencer mitti

[zakiuddin]

1. Catalytic Converter is installed by car makers to improve the quality of exhaust gases. It does not in any way improve car performance.
2. Cats cause restriction to air flow and hence are sometimes removed by track cars for increased performance.

In your particular case, There is a chance that plates installed by previous owner is restricting air flow but you should see a limit to RPM rather than increased time to achieve a top speed. Usual symptoms to what we experience with choked Cat converter but it doesn't seem to be the case here. So i don't think it has anything to do with Cat or plates.
Besides, a standard civic figure for 0-100 is 10 seconds, yours is just off by 3-3.5 seconds. I won't worry much about it.

[anarkaliantiques]

Good points, although i think talha is also on point with his assumptions. There are two O2 sensors in the exhaust, one before the cat and one after, it is necessary for the ECU to be able to monitor those voltages in order to create the optimum air-fuel mixture, Since the ecu doesn’t see that its running on “safe mode” so to speak and limiting fuel going to the fuel injectors as much as possible. The second O2 sensor is seeing all of the exhaust gases (without being catalysed) so it thinks car is still running rich and reducing the fuel pressure even further.
As the cars average is good, 15-16 on long i think car is performing well according to the current situation.

[zakiuddin]

here are two O2 sensors in the exhaust, one before the cat and one after, it is necessary for the ECU to be able to monitor those voltages in order to create the optimum air-fuel mixture, Since the ecu doesn’t see that its running on “safe mode” so to speak and limiting fuel going to the fuel injectors as much as possible. T

Pre-Cat O2 sensor is used for air-fuel mixture calibration to achieve the stoichiometric ratio, If the ECU/PCM does not see any signal from the Pre-Cat O2 sensor, it'll revert back to Pre-Mapped values in the ECU and issue a CEL. Most of the vehicles drive fine with CEL but some manufacturers push the car into limp mode so that the customer panics and gets it fixed on priority.
ECU will not limit the fuel to injectors unless it has enough evidence to conclude that the car is running rich.
Post-Cat O2 sensor is just there to monitor the health of Catalytic converter. ECU/PCM does not use it's signal for any performance tuning.

[anarkaliantiques]

Does that mean his car is in Limp mode, I find it kind of strange it is not common knowledge and they are limping cars by the hundreds-

[zakiuddin]

His car is not in Limp Mode. In limp mode either the Engine RPM is kept under 2000RPM or car has only one gear available (usually 3rd ); Implementation of Limp Mode is different across manufacturers.
Some manufacturers don't even choose to implement it.

[ali.qamar.372]

Tyre size please?
Which air filter are u using?
The timing is with ac or without ac?

[Thinking]

firstly never ever do that d1, d2, d3 thing manually in an auto car. its going to break your gear box.

regarding dragging an auto car we need to realize that its not a car designed for 0-100 time.

anyways you can get the alignment and balancing done o and use hi octane and than check. if it comes down to 12 sec, its good enough for a used car.

[aliaamar110]

odometer reading

[adnanofpk]

Tyre size is standard. 195/65/15 and brand new continental tyres. The time is without AC. I am using genuine air filter of honda. it costs me about 3 thousand.

[ali.qamar.372]

Why u replaced fuel pump and coils ?
Spark plug genuine?
Look like the desi catalytic is consuming more air