engine stalls intermitently

[yebo]

ehem, mawalang galang na po. ako naman ang magtatanong... car is mitsu lancer mx 2001 A/T, 38500km on the odo.

starting last august my ride would sometimes stall in the morning. di ko kasi gawa ang mag-warm-up so pag start as soon as the lights on the panel go off i shift into D, slow speed (up to 20-30 kph only) until the engine warms up then ok na. this was fine until starting last july/august the car would stall after going for a few hundred meters or more. i need to crank it up maybe 2 or 3 times then rev up to 2000+rpm for a minute before it will be ok again. di naman na mauulit for the whole day, even if the engine cools down later. this did not happen every day, siguro 1 every 2 weeks lang. and it only happens when the fuel level in the tank was less than 1/4 and when it was humid the night before (rainy season na nung nag-start ang problem).

i thought maybe i got bad fuel in the tank, first thing to suspect di ba. i was thinking that condensation was getting into the fuel tank at night since i had not been filling to full tank since the price of gas went up. so i had my fuel filters replaced last october and true enough there was water in the fuel filter. i also drained the gas tank a little (not completely, just a few liters) to check if there was still water in the gas tank. i put the gasoline inside a plastic bottle to settle and checked it the next morning. wala naman ako nakitang water, not a single drop. so i thought maybe i was right to think that it was just condensation that got into the tank during the night then eventually accumulated in the filter (hot tank after driving, then cool humid night = condensation in the tank, right?). it was ok after that.

lately it happened again, starting last january. it was not the usual once every 2 weeks but more frequently, siguro every 5 days or so. i did not mind it, wala ako time to fix kasi. but then my wife stalled 3 times already last week (she just learned to drive last november, so ang car na every month ang waxing e 5 na ang gasgas!) same conditions were present:

1. engine is still cold, having driven only a few hundred meters
2. it will be the first time to drive it for the day. it does not matter now if it is morning or afternoon, pero once it happens di na nauulit for the whole day.
3. after cranking again 2 or 3 tries it will fire up, need to rev a bit then ok na

some other symptoms but may be a different problem:
4. i would sometimes observe the idle speed go up and down after starting, then even out to 800 rpm. the engine sound is also more "bass" than the usual "baritone", parang naka-pineapple can free flow exhaust na (stock po lahat pati driver). this is very seldom. is this the ecu not being able to find the idle speed? sensor problem? it does not matter if the AC is on or not.
5. mileage is considerably down, nasa 6.8 km/l city and 12km/l highway na lang ako. before it was up to 10-11+/km/l city and 16+km/l highway on a light to moderate foot.
6. also, no check engine warning light. i do not know if there is an error code stored, pero wala naman check engine light kahit minsan. just the usual oil pressure and battery warning light when the engine stalls.

things done already since the problem appeared first:
1. changed fuel filter
2. change air filter
3. checked for water in the gas tank, none found
4. replaced spark plugs. the old ones were still in pristine condition, just a little carbon and yellowish-rust on the ceramic crown, probably from the bad fuel.
5. reset ecu. i disconnected the battery for 30 minutes then reconnected. i only allowed it to idle for less than 5 minutes after reconnecting the battery. i know it should be 20-30 minutes idling after the battery is reconnected but mahal na gas e hehehehe... do you guys think hindi nag-reset ng husto ang ecu and the minimum idle setting was not reassumed by the ecu that is why the engine would rough idle sometimes?

when i get home next week i plan to do the ff:
1. drain the gas tank completely, change the fuel filters again
2. clean the throttle body. i plan to completely remove it from the intake manifold para mas maganda ang linis. chance to make kalikot na din.
3. put injector cleaner in the gas tank

any other suggestions? do you think the servo is also at fault?

tia!

[boybi]

i've had a similar problem with my patrol a few years ago. kaso lang diesel fuel ito. the engine would stall after a few seconds, i have to pump the fuel filter para swabe ang start ng engine. when i replaced my fuel filters, wala sa tamang place yung o-ring which might have caused air to be sucked in from the fuel filters. but after replacing the fuel filters, hindi agad nawala yung problem. after around a week yata, bigla nalang bumalik sa normal

[StraightSix]

Mawalang-galang na rin ... 'di naman kasi ako mekaniko at iba rin ang sasakyan. Pero halos pareho ang problema ko nuon - engine stalls getting more frequent and rough idles. Upon restarting, naka-"limp mode" yung engine - mahina hatak at walang kabuhay-buhay. Walang ring error display sa panel.

I've checked the plugs, filter and used injector cleaners. I also tried to reset the ECU by disconnecting the battery. In the end, I had the ECU diagnosed for error codes and the culprit was the camshaft sensor.

[m_ron]

Mawalang-galang na rin ... 'di naman kasi ako mekaniko at iba rin ang sasakyan. Pero halos pareho ang problema ko nuon - engine stalls getting more frequent and rough idles. Upon restarting, naka-"limp mode" yung engine - mahina hatak at walang kabuhay-buhay. Walang ring error display sa panel.

I've checked the plugs, filter and used injector cleaners. I also tried to reset the ECU by disconnecting the battery. In the end, I had the ECU diagnosed for error codes and the culprit was the camshaft sensor.

You must have a euro car? base on the limp mode.

[m_ron]

Have the ecu scan for error codes.It could be a cam or crankshaft sensor.

[theveed]

My guess:

1) Dirty or defective MAF sensor
2) Dirty or near death injector
3) Cracked distributor cap or something with the distributor.

[NazQ]

5. reset ecu. i disconnected the battery for 30 minutes then reconnected. i only allowed it to idle for less than 5 minutes after reconnecting the battery. i know it should be 20-30 minutes idling after the battery is reconnected but mahal na gas e hehehehe... do you guys think hindi nag-reset ng husto ang ecu and the minimum idle setting was not reassumed by the ecu that is why the engine would rough idle sometimes?

may similar situation ako last weekend. I had scheduled a maintenance check for my gf's 7g galant last saturday, but I found out na naiwan sa reverse (R) yung shifter (matic). so drained yung battery, whew!

So ginawa ko tinangal ko yung batter sa auto ko (lancer 97-ck4a) and installed it in the 7G tapos pina-charge ko yung battery while I was having the car checked.

nung binalik ko yung battery sa lancer, di ko masyado pina idle (to let the ecu reset). ang result is namamatayan ako (engine stalls, head lights stays on, battery indicator on dash lights up).

ginawa ko ni-reset ko ng maayos yung ecu, disconnected/reconnected battery, idle for approx 15 mins with AC on, tapos nung wala na yung weird ticking sound oks na yung takbo.

pwede mo din check kung mahina na yung battery or madumi na yung posts. had this experience a year ago (similar to yours).

hope this helps..

[yebo]

ok thanks sa replies. i will add those things to my check list.

keep them coming guys, more ideas the better. tia!

[mazdamazda]

Hmmm... parang ganyan din ang 323 namin... out of the blue minsan bumabagsak ang RPM... kailangan lang ng alalay sa accelerator pedal para hindi mag stall.

Yung last time, talagang bagsak na ang RPM & undriveable na. Ginawa namin ni ian_rex ay baklas yung air intake... tapos binugahan ng carb cleaner yung throttle plates. Kaso nasobrahan yata nabuga at hirap mag start yung engine. Pero pagkatapos ng mga 6 tries, ayun... nag start na din ang makina.

[StraightSix]

You must have a euro car? base on the limp mode.

Yes, an early E46.