Fuel Knock??

[rsscertified]

hello po - ask ko lang if you also experience this on an automatic car, 1st gear and moving tapos hard press sa gas pedal to accelerate, meron light knock. Pero, kapag smooth press sa gas pedal wala naman knock na maririning.

I asked this kasi yesterday, kasi naririnig ko un kapag ginagawa ko ung hard press. Di ko naman ginagawa un talaga on a regular basis napansin ko lang nung one time kailangan ko lang magaccelerate ng mabilis. i'm using Petron Xtra unleaded (93+ Octane), 3 weeks ago po 10km checkup po nung car, napalitan po ung spark plugs, oil filter, change oil. Last last saturday, nagpakarga po ako ng XCS (95 octane), naririnig ko pa din po ung light knock. From the altis manual, dapat daw di ikabahala ung light knock. Kung heavy knock daw po eh dalhin na sa toyota dealer.

Yesterday also pina-road test ko po ung car. For some strange reason eh wala kaming narinig na knock, pinatakbo nya sa alabang ung car, umabot ng 130km wala po, very smooth.

Ask ko po opinions nyo mga experts, additional knowledge na din for me. Also, need ko nga ba ipacheck pa ito ng todo? May kinalaman po ba un sa pag press sa pedal?

Thanks po in advance

[v6dreamer]

Hopefully, it just about the octane gas are you using. Look in your owners manual and only use the proper octane.

But what you are describing sounds like one of the following; collapsed lifter, worn camshaft, excessive gap in the lower end (rod) bearing. If it has timing chain - that could be yet another source of this type of noise. The good news is if: it's still under warranty, if not $$$$. Go to the dealer(casa) and don't leave until they fix it because noise is minor, they'll start telling you that nothing is wrong hoping that the engine explodes right after the warranty is expired.

[rsscertified]

Hopefully, it just about the octane gas are you using. Look in your owners manual and only use the proper octane.

But what you are describing sounds like one of the following; collapsed lifter, worn camshaft, excessive gap in the lower end (rod) bearing. If it has timing chain - that could be yet another source of this type of noise. The good news is if: it's still under warranty, if not $$$$. Go to the dealer(casa) and don't leave until they fix it because noise is minor, they'll start telling you that nothing is wrong hoping that the engine explodes right after the warranty is expired.

Hi V6dreamer, thanks for your response. I'm really new on cars, so - collapsed lifter/worn camshaft etc I really don't know about those.

Yes this is still under warranty. 1 year pa lang po ito. Actually they have advised me to empty the gas tank before filling it up again then check if the noise is still there.

According po sa manual, 91 octane or higher is recommended. Since I got it, I'm using xtra unleaded from Petron which is 93+ octane. just recently I used XCS since they said it's much better for mileage.

This morning, while I drive to office, I'm trying to check kung merong noise pa din, binalik ko sa smooth press sa pedal ng gas, seems to be fine naman. baka na sa pag biglang apak ng gas medyo may light knock.

[v6dreamer]

What is XCS?
Proper maintenance in your car is always your best bet of better milage and they way you drive....nothing else. The rest......use at your own risk.

[niky]

Might have been bum gas.

No brand new car should knock on sudden prods of the throttle. With electronic fuel injection and O2 sensor mediated fuel trimming, it's next to impossible.

[rsscertified]

What is XCS?
Proper maintenance in your car is always your best bet of better milage and they way you drive....nothing else. The rest......use at your own risk.

Hi V6Dreamer, it's a name for unleaded gas here in Manila that has 95 RON
http://www.petron.com/fueljourneys/f...fuels-pxcs.asp

Might have been bum gas.

No brand new car should knock on sudden prods of the throttle. With electronic fuel injection and O2 sensor mediated fuel trimming, it's next to impossible.

Hi Niky - thanks for your response. May I ask - what do you mean with bum gas? I apologize, I'm really new with engines.. What should I do? Do I need to change to a new fuel? Thanks!

[normanenoza]

did they check if ok pa yung knock sensor mo. a busted knock sensor will never trigger the check engine light. IMHO, using gas with higher octane rating than the recommended is just a waste of money. remember this, it is already the recommended gas specified in the manual and not the minimum required. your engine will just utilize the same amount of heat irregardless of the octane rating of the gas.

[rsscertified]

did they check if ok pa yung knock sensor mo. a busted knock sensor will never trigger the check engine light. IMHO, using gas with higher octane rating than the recommended is just a waste of money. remember this, it is already the recommended gas specified in the manual and not the minimum required. your engine will just utilize the same amount of heat irregardless of the octane rating of the gas.

hi normanenoza, thanks for your reply - sir where can I check the knock sensor? altis po tsikot ko. inuubos ko na lang ung tank ko and will go back to xtra unleaded.

[bratski]

rss
i had the exact same problem as yours a few weeks ago, although innova gas matic yung sa akin, but the fuel i use is also petron extra unleaded. nagkakaron din ng knocking under hard acceleration but under normal circumstances wala naman. i changed sparkplugs, fuel filter(grabe ang mahal nito), cleaned the maf sensor, o2 sensor. ganun parin. so i tried switching to xcs(higher octane) and still ganun parin. pina check ko sa friend ko na may talyer and what he did is binaba fuel tank and empty its contents and replaced with petron blaze(96 octane), cleaned my injectors, ayun nawala na knocking even under hard acceleration and uphill climbs. turns out hindi ata compatible yung unleaded and xcs ng petron sa ride ko. my manual also recommends a minimum of 91 octane pero ang extra unleaded is 93 octane na. so what gives? ang mahal pa naman ng blaze and hindi naman high performance ang innova to use that fuel. imo burning money lang ako sa ganitong situation and im looking to change to caltex or shell.

[bratski]

hi normanenoza, thanks for your reply - sir where can I check the knock sensor? altis po tsikot ko. inuubos ko na lang ung tank ko and will go back to xtra unleaded.

knock sensors are usually located on the engine block near the intake manifold, to check if its working get a wrench or some hard object and lightly knock on the area near the knock sensor (not on the sensor itself,with the engine idling), you will notice na may magbabago sa timing mo, the sensor will retard timing if it senses knock (assuming working nga yung sensor, it it doesn't, probably sira).if sira knock sensor, you have to replace it($$$) pero mahirap ma sense kung nag iba nga yung timing if wala kang timing light. your best bet would be to empty your tank and try other fuels. minsan compatibility issue ito. ako i learned it the hard(expensive) way.

[rsscertified]

rss
i had the exact same problem as yours a few weeks ago, although innova gas matic yung sa akin, but the fuel i use is also petron extra unleaded. nagkakaron din ng knocking under hard acceleration but under normal circumstances wala naman. i changed sparkplugs, fuel filter(grabe ang mahal nito), cleaned the maf sensor, o2 sensor. ganun parin. so i tried switching to xcs(higher octane) and still ganun parin. pina check ko sa friend ko na may talyer and what he did is binaba fuel tank and empty its contents and replaced with petron blaze(96 octane), cleaned my injectors, ayun nawala na knocking even under hard acceleration and uphill climbs. turns out hindi ata compatible yung unleaded and xcs ng petron sa ride ko. my manual also recommends a minimum of 91 octane pero ang extra unleaded is 93 octane na. so what gives? ang mahal pa naman ng blaze and hindi naman high performance ang innova to use that fuel. imo burning money lang ako sa ganitong situation and im looking to change to caltex or shell.

Thanks for your response bratski, actually yan ang gagawin ko ngaun, ubusin till empty ung fuel tank ko. Nakupo mahal ung blaze Kakapagtaka pano hindi naging compatible na ung unleaded and xcs pareho tayo sir 91 and recommended octane sa manual. Di kaya madumi din ung injectors nung tsikot ko? medyo taka din ako sa part na un kasi just 3 weeks ago, nag 10k checkup po ito.. waaaahh!!!

[bratski]

Thanks for your response bratski, actually yan ang gagawin ko ngaun, ubusin till empty ung fuel tank ko. Nakupo mahal ung blaze Kakapagtaka pano hindi naging compatible na ung unleaded and xcs pareho tayo sir 91 and recommended octane sa manual. Di kaya madumi din ung injectors nung tsikot ko? medyo taka din ako sa part na un kasi just 3 weeks ago, nag 10k checkup po ito.. waaaahh!!!

just spoke with the owner of the petron station na pinagkakargahan ko ng gas, turns out my innova has ingested bad gas nga dahil nung time na nagpakarga ako nag maintennance sila ng mga pumps, nalagyan siguro ng dumi at nagbara yung fuel filter ko.2 of my other delivery vehicles also nagpakarga din nung araw na yun(xtra unleaded din) and mas malala nangyari (one of them nawala yung power). rather than lose a longtime volume customer, the owner decided to reimburse me for my gas and repairs for the vehicles affected. good thing tumawag siya kasi i was about to seal a deal with another petron station across the street hehehe.P.O. system kasi ako sa petron for my personal vehicles and my delivery trucks.
by the way, pag naubos na yung current gas mo and maglalagay ka ng bagong gas, after the fill up palit ka na ng fuel filter dahil malamang nagbara narin yan due to bad gas. yung fuel injectors tsaka mo nalang palinis kung may knocking ka parin naririnig after changing the fuel filter. im not sure about the fuel filter of the altis pero kung plastic type yan medyo mura lang, pero kung metal type with the brackets pa ang mahal sobra. fuel filter ng innova ko costs almost 3k (genuine)

[rsscertified]

just spoke with the owner of the petron station na pinagkakargahan ko ng gas, turns out my innova has ingested bad gas nga dahil nung time na nagpakarga ako nag maintennance sila ng mga pumps, nalagyan siguro ng dumi at nagbara yung fuel filter ko.2 of my other delivery vehicles also nagpakarga din nung araw na yun(xtra unleaded din) and mas malala nangyari (one of them nawala yung power). rather than lose a longtime volume customer, the owner decided to reimburse me for my gas and repairs for the vehicles affected. good thing tumawag siya kasi i was about to seal a deal with another petron station across the street hehehe.P.O. system kasi ako sa petron for my personal vehicles and my delivery trucks.
by the way, pag naubos na yung current gas mo and maglalagay ka ng bagong gas, after the fill up palit ka na ng fuel filter dahil malamang nagbara narin yan due to bad gas. yung fuel injectors tsaka mo nalang palinis kung may knocking ka parin naririnig after changing the fuel filter. im not sure about the fuel filter of the altis pero kung plastic type yan medyo mura lang, pero kung metal type with the brackets pa ang mahal sobra. fuel filter ng innova ko costs almost 3k (genuine)

thanks Bratski - naku mahal pala ung fuel filter. problem ko din di ko alam kung san nakalagay ung fuel filter. san po pede magpapalit kaya nito sir kung sakali?

[lazyfoot]

i experience a slight fuel knock with my altis, i use unleaded. i only notice it during hard accelerations and only if my window is down, otherwise i don't notice it at all. is it ok to have slight knock? i use unleaded fuel.

[normanenoza]

i experience a slight fuel knock with my altis, i use unleaded. i only notice it during hard accelerations and only if my window is down, otherwise i don't notice it at all. is it ok to have slight knock? i use unleaded fuel.

all gasoline available in the market are unleaded. please specify the exact brand and octane rating you used.

[bratski]

thanks Bratski - naku mahal pala ung fuel filter. problem ko din di ko alam kung san nakalagay ung fuel filter. san po pede magpapalit kaya nito sir kung sakali?

most fuel filters are located in the engine compartment, you will know its a fuel filter dahil yun line ng gas from the fuel tank diretso sa kanya and another line coming out directly sa fuel injectors. medyo easy fix lang pag sa engine compartment siya located,some fuel filters are located underneath the vehicle naman.but a friend who has a 1.8 altis told me that yung fuel filter niya is located very near or on top of the fuel tank itself kaya kailangan pang ibaba yug fuel tank niya to access the filter (eto madugo sa labor charges).

[lazyfoot]

all gasoline available in the market are unleaded. please specify the exact brand and octane rating you used.

Shell unleaded 93 octane

[daimaoh]

engine knocking is usually heard from when the car is not moving or at very low speed then going into accelaration and/or when going uphill. not by doing 130kph.

engines have a minimum required octane rating. check your manual. if knocking persists, have your timing adjusted or switch to a higher octane fuel.

[RepotSirc]

anyone here using Petron Xtra Unleaded for their Mazda 3 1.6V variant?

I wonder if you can post your review here.

thanks in advance.

[s_quilicot]

most fuel filters are located in the engine compartment, you will know its a fuel filter dahil yun line ng gas from the fuel tank diretso sa kanya and another line coming out directly sa fuel injectors. medyo easy fix lang pag sa engine compartment siya located,some fuel filters are located underneath the vehicle naman.but a friend who has a 1.8 altis told me that yung fuel filter niya is located very near or on top of the fuel tank itself kaya kailangan pang ibaba yug fuel tank niya to access the filter (eto madugo sa labor charges).

hmmm. the fuel filter of the 1.8 altis (i have the same model) is can be replaced without taking the fuel tank.

tanggalin mo lang yung upuan sa likod and bang. fuel filter na.

i had mine repalced sa speedyfix. mejo pricey lang ang fuel filter (grnuine) for altis.