Help: Engine crank but fails to start

[t2erns]

hay naku ano naman kaya magagawa ng planta sa kaso na ito. share ko lang, last week I had a 2006 civic no start then galling casa, ang naging problema ay bad ground lang (the 12v supply sa crankshaft sensor ay dropping out, catched the glitch by oscilloscope).
i'm not saying na yan problema ng civic nyo but it will help to check all powers and ground.

[clei_torres]

noted po t2erns. tnx

[clei_torres]

Casa's mostly operate with apprentice, maybe 2 or 1 are the only real mechanic that you wouldnt really call experts. They are only good reading codes and troubleshooting by the books. Those experienced and good mechanics were long gone working abroad. You'd sometimes better off with roadside talyer having more experience in troubleshooting.

TS, if you're suspecting immobilizer shutting your injectors then start working with the immobilizer. Possibilites are your computer got fried or needs reprogramming. Swapping parts could be the best way to check. Dalhin mo yan sa banawe, tapos na yan.

Sir meron po sila spare computer box and sensors. na try na daw nila i swap pero ayaw talaga, aside from that nakiki communicate daw yung computer ko sa computer nila.

[t2erns]

Sir meron po sila spare computer box and sensors. na try na daw nila i swap pero ayaw talaga, aside from that nakiki communicate daw yung computer ko sa computer nila.

that's a good indication that the issue is more likely a wiring issue (power and grounds as I posted earlier)

in my case IIRC it's the ground G101 (hidden beside the throttle body), that ground supplied the ground for the pcm, being intermittent the pcm loses power momentarily. that's the reason the ground supplied by the computer to the coil side of the pgmfi relay is also lost and that will skew the readings of the sensors like crankshaft position sensor and thus the no start condition. the glitch is very intermittent and very fast that no digital tester can catch (I used oscilloscope to catch the glitch).

[clei_torres]

that's a good indication that the issue is more likely a wiring issue (power and grounds as I posted earlier)

in my case IIRC it's the ground G101 (hidden beside the throttle body), that ground supplied the ground for the pcm, being intermittent the pcm loses power momentarily. that's the reason the ground supplied by the computer to the coil side of the pgmfi relay is also lost and that will skew the readings of the sensors like crankshaft position sensor and thus the no start condition. the glitch is very intermittent and very fast that no digital tester can catch (I used oscilloscope to catch the glitch).

Sir na quote ko napo yung message nyo sa SA ko, ang sagot sakin na check na namin, update nalang daw po ako kung umandar na kotse...ewa ko ba kung ano pa gagawin nila

[ampiang]

Pa F1 naman po ako

Meron po akong problema sa mitsu El carburetor type kapag coldstart po kasi in the morning pag start mamamatay din agad unless sabayan mo ng acceleration ano po kaya pinaka possibleng problema ng itlog ko mga sir's please pa F1 po ako tnx more power sa lahat ng may itlog

[t2erns]

binalikan ko yung first post nyo, bago nasira alternator maayos naman andar ng car? how about the alternator, original ba ang pinalit? may ginawa ba conversion sa wiring ng alternator? na try na ba paandarin na tanggal ang wiring ng alternator?

[clei_torres]

Ngayon lang na detect sira. Sira daw po catalytic converter kaya ayaw umandar makina. Mahal ng quote ng casa for catalytic converter P42K! San po kaya makakamura? Re alternator, denso po nabili ko, kamukhang kamukha po ng stock na alternator at same ang spec. na mitsubishi ang tatak ng oem alternator. Wala pong ginalaw sa wirings. Maayos din po andar nya before

[s10pao]

Ngayon lang na detect sira. Sira daw po catalytic converter kaya ayaw umandar makina. Mahal ng quote ng casa for catalytic converter P42K! San po kaya makakamura? Re alternator, denso po nabili ko, kamukhang kamukha po ng stock na alternator at same ang spec. na mitsubishi ang tatak ng oem alternator. Wala pong ginalaw sa wirings. Maayos din po andar nya before

sira catalytic converter pero wala ka CEL related sa O2 sensor? ung iba nga tinatanggal talaga ang catalytic converter umaandar pa rin naman kotse nila.

[clei_torres]

Ewan ko nga sir. Pero sabi ng SA nung tinangal catalytic converter umandar daw makina

[t2erns]

Ewan ko nga sir. Pero sabi ng SA nung tinangal catalytic converter umandar daw makina

so na cho-choke ang engine and hindi makahinga (simple mechanical problem). they could easily catch that if they use a vacuum gauge sa engine.

about the pcm not throwing a code MAYBE walang oxygen sensor (not so sure about that) ang Honda after the catalyst so walang catalyst efficiency monitor. very common sa Japanese cars dito sa atin na walang downstream oxygen sensor.

having a working catalytic converter will help the environment but will rob your wallet, he he

am glad to hear na finally na nail down na ang problema.

[s10pao]

Ewan ko nga sir. Pero sabi ng SA nung tinangal catalytic converter umandar daw makina

barado na agad? ang bilis naman. check mo rin kung catalytic converter talaga ung barado, baka kasi may tumarantado sayo at binarahan ung exhaust mo.

patanggal mo muna tapos hanap ka ng surplus.

[clei_torres]

Noted mga sirs. Thanks po sa mga input