Ask Xulfiqar - An Automotive Encyclopedia

[metalhead]

@xulfiqar
Recently i noticed slight pinging around 1.5k rpm in my 02" civic exi. What possible reasons can cause this?
Also had to clean the throttle body as the engine was stalling on switching off ac at idle. This problem is now gone. Wanted to check the MAP sensor but it's screw is jammed. If i somehow open it can it be cleaned or should i buy one?

The pinging is still there between 1.5 to 2k rpm. Refilled the petrol from other station but no difference. Can the cng advancer disturb the timing on petrol also?

[Xulfiqar]

The pinging is still there between 1.5 to 2k rpm. Refilled the petrol from other station but no difference. Can the cng advancer disturb the timing on petrol also?

the MAP sensor cannot be cleaned - if you spray anything in it, it will go bad.

• the spark advancer of the CNG can cause pinging/knocking - if its malfunctioning. Make sure its actually switching off when you convert to petrol.

[metalhead]

the MAP sensor cannot be cleaned - if you spray anything in it, it will go bad.

- the spark advancer of the CNG can cause pinging/knocking - if its malfunctioning. Make sure its actually switching off when you convert to petrol.

Can the MAP sensor be fouled by the greasiness in the intake manifold?

And I will checkout the advancer switching off on petrol. Thanks.

[taimoor.sultanchaudhry]

xulfiquar Bhai what are some of the salient things that I MUST inspect (engine wise) while buying ten year old sedans (specifically Nissan Sunny or Mitsubishi Lancer) with more than 100k on the odo. I wil appreciate if you could explain in lay man terms. Much appreciated and reply awaited.

R/
Taimoor

[AlienX]

@Xulfiqar

AOA. Short Question before I go ahead on having the cleaning performed.

Throttle Body: What it is, and why it needs cleaning ?

I recently had to replace the fuel pump for Vitz 2005 I have. After that the mechanic went through OBD readings and recalibrate the engine. But told me that throttle body needs cleaning. Though the Car has improved performance but still sometimes gives gaps in ignition, most at rest or slow reverse. These gaps are usually very short, 10-50 ms. But enough to tell that it's happening, does it mean there are breakage in wires and need replacement ?

Also has long self and sometimes starts on second self when cold.

Also what is average milage before a CVT fluid should be changed. Mine has run for 40K.

Thanks.

[khilji74]

Polo is an electrician. Near landi kotal chorangi some one on this forum told me about him. And I dont know about the gear model how can I find about tha gear model and i want to know What is DLc?

[Maverickiz3d]

Polo is an electrician. Near landi kotal chorangi some one on this forum told me about him. And I dont know about the gear model how can I find about tha gear model and i want to know What is DLc?

DLC is data/diagnostic link connector. Its a connector with the ECU wiring to connect it to the scan tool.

[khilji74]

Yes it is installed DLC

[syncview]

@Xulfiqar

AOA. Short Question before I go ahead on having the cleaning performed.

Throttle Body: What it is, and why it needs cleaning ?

I recently had to replace the fuel pump for Vitz 2005 I have. After that the mechanic went through OBD readings and recalibrate the engine. But told me that throttle body needs cleaning. Though the Car has improved performance but still sometimes gives gaps in ignition, most at rest or slow reverse. These gaps are usually very short, 10-50 ms. But enough to tell that it's happening, does it mean there are breakage in wires and need replacement ?

Also has long self and sometimes starts on second self when cold.

Also what is average milage before a CVT fluid should be changed. Mine has run for 40K.

Thanks.

Gaps in ignition? What do you mean by gaps here?

fuel pump was changed.. with a brand new part? fuel filter too?

40K is about time, CVT fluid should be changed around this interval
Long starting can be caused by a lot of things again, was the installed fuel pump new? was the fuel pressure checked before and after the installation?

[ahmed8ty9]

please find a good mechanic - this is not a DIY job for most. For someone with good tooling and working knowledge, its a 4 hour job at max, including brake service. If the diffy input shaft seal is leaking then make sure that someone qualified services the differential. Reason to say this is because if they mess up the pinion position on the crownwheel your differential will grenade itself in a few thousand kms.

@xulfiqar thank you

There is no visible leak from axle or differential. The only fluid leak is from the gear area. After checking from under side my mechanic has told me there is oil leaking from a point inside the accelerator cable joint which was repaired before this event, there is a seal inside it that needs to be reinstalled or reset at its proper position.

As far as rear axle there is no fluid or leak he could find, however there will be some small work done on "goday" to avoid wheel lock.

kindly advise if you recommedn any additional action

[saboor73]

xulfiquar Bhai what are some of the salient things that I MUST inspect (engine wise) while buying ten year old sedans (specifically Nissan Sunny or Mitsubishi Lancer) with more than 100k on the odo. I wil appreciate if you could explain in lay man terms. Much appreciated and reply awaited.

R/
Taimoor

See if the car is swapped if not than inspect car like you so with normal engine health,suspension etc

[rhjunejo]

Dear Xulfiquar bhai, i posted this problem earlier, if u could guide me through.........I have corolla GLI 2010, and there is a problem with my car, this is happening second time. After driving around one hour, when in idle i press the clutch the rpms go high around 2300 and stay there while the clutch is pressed, and the engine check light comes on. The last time this happened the mechanic guy told me that clutch plates are done, i changed the plates (in Aug this year), but now same thing is happening. Also when this happens, the car looses the pick. Is this the clutch again or something else? and can it b so that clutch plates are done in this time period? please you or any other guru here help me.
thnanks

[AlienX]

Gaps in ignition? What do you mean by gaps here?

fuel pump was changed.. with a brand new part? fuel filter too?

40K is about time, CVT fluid should be changed around this interval
Long starting can be caused by a lot of things again, was the installed fuel pump new? was the fuel pressure checked before and after the installation?

Yes, both the fuel filter and fuel pump are new. Fuel pressure what checked before and after change on pump. Previously it was 10-15 and after change it increased to 45-55.

By gaps in ignition, what happens is when I start the car, it take a long self (but sometimes short/normal) to start. The engine RPM doesn't stay stable while at rest, for example dropping to lowest and increasing to stay running. This causes the car to sometimes turn-off on signals but mostly when in 'D'.

I tried to reset the ECU by disconnecting the battery for 1-2 minutes, it improved RPM to great extant but have not eliminated the issue.

Another concern is engine sound. After recalibration, the sound has increased considerably, especially during acceleration but when stable at a speed it gets normal. For example when going from 0-50 Km/h it sounds like a jeep. but when reaching the desired speed it gets silent. May be CVT fluid is the reason here.

[SER_GTR]

Yes, both the fuel filter and fuel pump are new. Fuel pressure what checked before and after change on pump. Previously it was 10-15 and after change it increased to 45-55.

By gaps in ignition, what happens is when I start the car, it take a long self (but sometimes short/normal) to start. The engine RPM doesn't stay stable while at rest, for example dropping to lowest and increasing to stay running. This causes the car to sometimes turn-off on signals but mostly when in 'D'.

I tried to reset the ECU by disconnecting the battery for 1-2 minutes, it improved RPM to great extant but have not eliminated the issue.

Another concern is engine sound. After recalibration, the sound has increased considerably, especially during acceleration but when stable at a speed it gets normal. For example when going from 0-50 Km/h it sounds like a jeep. but when reaching the desired speed it gets silent. May be CVT fluid is the reason here.

1KR Is Noisy Itself....It Can Be Tranny Also Which Sound....Your CVT Oil Replacement Is Almost On Peak So Do It....! Usually 40k Change Is On Safe Side Whereas 50k Is Maxx You Can Go...!

[SER_GTR]

Dear Xulfiquar bhai, i posted this problem earlier, if u could guide me through.........I have corolla GLI 2010, and there is a problem with my car, this is happening second time. After driving around one hour, when in idle i press the clutch the rpms go high around 2300 and stay there while the clutch is pressed, and the engine check light comes on. The last time this happened the mechanic guy told me that clutch plates are done, i changed the plates (in Aug this year), but now same thing is happening. Also when this happens, the car looses the pick. Is this the clutch again or something else? and can it b so that clutch plates are done in this time period? please you or any other guru here help me.
thnanks

How Much Car Is Driven After You Replace Clutch/Pressure

LOgically It Makes No Sense That Idle RPM Are Raised When You Press Clutch....If It Happen When You Press Clutch....It Should Also Do Same WHile Car Is In Neutral...Did You Check That???

Since Its Manual Transmission ...i see no connection of RPM Going High While Clutch Pressed..Even If Your Clutch Is Worn-Out...

CEL Also Have Nothing To Do With Clutch M/T....It Might Be Some Throttle Issue Or IDle Issue...You Should Get Your Car OBD Scanned

[rhjunejo]

How Much Car Is Driven After You Replace Clutch/Pressure

LOgically It Makes No Sense That Idle RPM Are Raised When You Press Clutch....If It Happen When You Press Clutch....It Should Also Do Same WHile Car Is In Neutral...Did You Check That???

Since Its Manual Transmission ...i see no connection of RPM Going High While Clutch Pressed..Even If Your Clutch Is Worn-Out...

CEL Also Have Nothing To Do With Clutch M/T....It Might Be Some Throttle Issue Or IDle Issue...You Should Get Your Car OBD Scanned

Car is driven around 2.5K after the clutch replacement. And it doesnt happen in neutral. When this happens car looses all the power, i accelerate and honestly no response, baht mshklon se main islamabad se taxila puhuncha. Now i m looking to find the problem and then go to mechanic.

[SER_GTR]

Car is driven around 2.5K after the clutch replacement. And it doesnt happen in neutral. When this happens car looses all the power, i accelerate and honestly no response, baht mshklon se main islamabad se taxila puhuncha. Now i m looking to find the problem and then go to mechanic.

It Can Possibly Be A Sensor Issue...I Doubt ...OBD SCAN Can Tell Exactly Whats Happening.....You Can Disconnect Battery +ve Terminal And Connect Again After 5 Min And See If It Helps....!

The CEL blinking Def Shows Something Is Wrong Electrically!

[SER_GTR]

You Can Also Check Grip Of Throttle Sensor And Others And See If Any Of It Is Loose....!

[syncview]

Yes, both the fuel filter and fuel pump are new. Fuel pressure what checked before and after change on pump. Previously it was 10-15 and after change it increased to 45-55.

By gaps in ignition, what happens is when I start the car, it take a long self (but sometimes short/normal) to start. The engine RPM doesn't stay stable while at rest, for example dropping to lowest and increasing to stay running. This causes the car to sometimes turn-off on signals but mostly when in 'D'.

I tried to reset the ECU by disconnecting the battery for 1-2 minutes, it improved RPM to great extant but have not eliminated the issue.

Another concern is engine sound. After recalibration, the sound has increased considerably, especially during acceleration but when stable at a speed it gets normal. For example when going from 0-50 Km/h it sounds like a jeep. but when reaching the desired speed it gets silent. May be CVT fluid is the reason here.

You can try cleaning the throttle body, but don't dunk it in petrol or throttle cleaner, use a clean cloth, spray some cleaner on it and wipe the TB bore out and thats it.

Hard starting can be caused by many factors, the fuel pressure seems to be good.
This can also be a problem due to a leaky injector, how quickly does the system lose fuel pressure ?
It should stay above 21psi for at least 5 mins after engine off.

other things that contribute to hard starting are spark plugs, really worn out plugs.

the 1kr is a very noisy engine nothing can be done about that.

[AlienX]

You can try cleaning the throttle body, but don't dunk it in petrol or throttle cleaner, use a clean cloth, spray some cleaner on it and wipe the TB bore out and thats it.

Hard starting can be caused by many factors, the fuel pressure seems to be good.
This can also be a problem due to a leaky injector, how quickly does the system lose fuel pressure ?
It should stay above 21psi for at least 5 mins after engine off.

other things that contribute to hard starting are spark plugs, really worn out plugs.

the 1kr is a very noisy engine nothing can be done about that.

@ser_gtr

Spark plugs: unlikely as they have been changed about 20K milage earlier.

1KR Engines are noisy, I am at peace with that already. Today I went to have the silencer and dholki checked and they seem to be in good condition. I remember once I actually did succeed to make the car sound bearable by using an STP fuel injector cleaner. It made the engine sound almost 50% less. I'll try it again.

I normally use HOBC mixed with regular which fixed knocking.

But I didn't find Toyota CVT Fluid today, they say it's short. But there is another KIXX CVT Fluid too, about 2900Rs, Mechanic says he used it and gives good results but I am not convinced. I used their Engine Oil but shifted to LiquiMoly recently with 5W-40 rating.

There are no significant error on ODB, a busted ABS sensor and that's it. Short term value was at -20 but after fuel pump changed it returned to normal. I'll have the values checked again.

My highest priority is to have the CVT Fluid changed.