Need Help!! idling problem

[blacksun25]

Hello Everybody. I am just new here and I need your help. I just purchased a second hand car, a 1992 Nissan Sentra ECCS. Namamatay kasi makina ko pag hindi naka-ON yung aircon or kapag nag-automatic shut-off na yung compressor. Giniginaw na ko sa aircon pero di ko naman ma-turn off kasi namamatay makina ko. Tsaka there are times na ayaw ko talaga mag aircon for fuel economy reasons. Any inputs will be highly appreciated. Can you also recommend a good shop? Thanks.

[istan]

Sounds like my sentra months ago. What I did was go to the casa, let them fiddle around with my throttle cable. Found out that your neighborhood mechanic should not touch those cables because if they're out of alignment, engine won't run well.

Anyway, Take your Sentra to the casa, let them check out the throttle cable, w/c is in front to the ECCS. Let them check via computer, your compression and sensors. LEt them clean your sensors too.

Cost me less than 2k to do it. But after that...ok na ok ang car.

Oh yeah, also let them check your spark plugs. You might have the wrong sparkies... ie Cefiro type/Platinum - Inde raw pwede yun sa 1.6L ECCS engine

[niky]

Sounds like a cable or your idle screw isn't set right.

Kung under 2k yung service na yun... sulit na... which casa was that?

[afrasay]

Advice ko lang sa mga bumili ng EFi (with computer) na engine na may problema o kahit na yun wala, dalhin sa casa for a one time check-up and computer diagnostic. after that don't tinker with your car. it takes out the guess work of troubleshooting plus you'll know your car is running up to specs. the TS made the right decision.

[blacksun25]

maraming salamat po sa lahat ng nag-advise. i think you guys are right, i'll try to bring it sa casa for diagnostics and check-up. It makes sense to leave the tinkering to the professionals who have the right equipment and training.

Sir Istan, saang casa po yung pinagpagawaan niyo?? i'm afraid kasi pumunta sa mga casa, baaka tagain lang ako at papalitan ang hindi naman kailangang palitan which was my experience before with my previous car. meron ba kayong mai-rerecommend na casa and contact person?

salamat po ulit and more power!!!

[niky]

Never did like Mantrade. Too crowded, so you don't get good service... but my problem was I lived very far away, so hindi ko sila kayang tutukan. It might be different now, though (we sold our Nissan five years ago.

Ang tip ng uncle ko who did get good service at Mantrade? Go in with the car on your first visit, and if the job looks like it'll take a while, offer smokes and/or drinks to the service crew working on the car. A little PR goes a long way.

[blacksun25]

just to update you guys: Dinala ko kahapon sa Nissan Commonwealth/ Prince motors yung car ko for diagnostics. They found that the "AAC valve" is not functioning properly. apart from that they also suggested to replace the following parts:

power steering suction aand return hose
distributor oil seal and gasket
valve cover gasket
high tension wires
replace plugs
fuel filter

I have asked about the estimated cost. The AAC valve alone costs P7,000. Sabi ko ay mag-try muna ko maghanap sa mga japan surplus shop. I paid the diagnostic fee (P680) and went on my way to Banawe to look for the AAC valve.

On my way home, napansin ko na hindi na namamatay yung makina ko kahit hindi ako naka- aircon!!

Hindi ko alam kung ano nangyari??? Ang napansin ko lang ay medyo tumaas yung RPM ko. Minsan kahit naka idle lang ay tumataas siya ng 1300 rpm. pero minsan ay bumababa naman sa normal 900-1000rpm.

Question: Kailangan ko pa rin kayang palitan yung AAC valve ko? Or kaya nang ayusin ng tune-up yung pagtaas ng RPM ko?

Meron ba kayong alam na makukuhaan na surplas ng AAC valve, if so magkano kaya?

Thanks po ulit sa lahat.

[afrasay]

What is the AAC sensor for? What does it sense? What does it look like? What does AAC means? Where is it? These are the questions you should've ask when they gave you their findings. Try mong mag canvass sa mga Nissan parts dealer, like Nisway 6473746. The other parts they mentioned puwede na sa labas pagawa. Pakiramdam ko aircon related ito (AAC) like an idle up sensor. IOf this is what I think it is mga 150 to 350 php lang ito surplus. BRW, your normal rpm should be around the 750 to 800 range, wiht or without aircon. Malamang they made a few adjustment to compensate sa aircon load mo kaya di na namamatay engine when it is off.

[blacksun25]

sir afrasay, sabi nung mekaniko "Auxilliary Air Control" valve ang ibig sabihin ng AAC. I don't know what it does since this is the first time that I have owned an EFI car. Puro carburator type car ko before. Nagtanong-tanong ako sa Banawe kahapon pero wala ako nahanap na AAC valve

[afrasay]

Does it have two terminal for wiring and input and output hose connection?

[blacksun25]

Does it have two terminal for wiring and input and output hose connection?

Di ako sigurado sir afrasay kung ilan terminal and hoses. double-check ko mamaya at try ko picturan. Salamat po ulit.

[afrasay]

Eto ba siya?
http://autorepair.about.com/library/faqs/bl612f.htm

[blacksun25]

sir afrasay, sorry hindi ko alam kung parehas ng AAC valve sa diagram mo yung sa car ko. DI ko siya mapicturan ngayon kasi iniwan ko sa bahay yung car. I have inserted 2 images (from the classified sections). I have marked the AAC valve as the mechanic pointed out. Sorry at medyo malayo. I'll try to get better pictures later pag-uwi ko.

[yourman]

i had similar problem with my xtrail, rough/low idling when the aircon is on. I guess your problem is the opposite that the idle is too low when the aircon is off. but both problem is caused by the AAC. The AAC controls the airinflow to the engine that controls the idling when the aircon is on/off. Unlike the carburator type, the efi engines' idling is controlled/maintained at the same level whether the aircon is on or off.

Mine was fixed with the cleaning of the AAC since its just 3 yrs old. Yours needed to be replaced.

But maybe cleaning can fix your problem. But if ever you choose to replace it, dont go for surplas sir, baka in a month or too, labas na naman problem mo. If you plan to keep your sentra for a long time, replace it with the new one. however, my old mits montero had the same problem also, rough idling when the aircon is off, i forgot the name of the part for mitsu but same as the aac of nissan. got a surplas replacement from banawe since i was about to sell it anyway, fixed it and sold it.

or if the change in idling doesnt annoy you, you just increase the idling so when the aircon is off, your engine will not stall.

just my 2 cents...

[afrasay]

Ah, the equivalent part for that in an M111 engine of a C class Mercedes-Benz is the Idle Control Valve. It cost 25 thou new. So there you have it, go for a new one as mentioned by yourman.

[blacksun25]

Salamat po sa mga advise niyo sir afrasay and yourman. Tomorrow ko na lilinisin yung AAC valve ko along with the other sensors. Pag-nakuha then good for me. pag-hindi, then my pocket would be P7000 lighter! hehehe.

[knight21]

nangyari na sa akin 'to.

kailangan lagi naka-on yung aircon otherwise mamatay makina kapag tumitigil. i tried to clean the aac valve pero ganun pa rin. nung nagpalit ako ng surplus, nag okay na ulit yung idle.

you can try to clean the aac first and see kung may improvement. if not then it's time to replace the aac valve.

[blacksun25]

update ko lang kayo mga sirs. nalinis ko na yung AAC valve ko pero ganoon pa rin idling ko. looks like kailangan na talagang palitan.

Sir knight21, saan kayo nakakuha ng surplus na AAC valve and how much? Thanks.

[afrasay]

if you intend to keep the car with you for a long time go brand new. na check mo na ba yun mga air hose mo?

[blacksun25]

if you intend to keep the car with you for a long time go brand new. na check mo na ba yun mga air hose mo?

na-check ko na rin sir. yung ibang malutong na hose, napalitan ko na rin. I really plan to keep the car for a long time that's why i'm trying to fix all the mechanical problems. I really wanted to restore her former glory and make her road worthy again.

naisip ko kasi kung makakakuha ko ng surplus na AAC valve for 1K that works (compared to brand new which costs 7K), I would still have budget for other parts that needs to be repaired/ replaced. Anyways, tuloy pa rin ako sa pag-canvas ng parts. balitaan ko kayo kung ano man maging desisyon ko.

salamat po ulit sa lahat ng advise. malaking tulong talaga ang tsikot.com sa mga tulad kong newbie sa 4 wheels!