Issues when accelerating

[dan765]

Hello Gents.

2009 Saturn Astra, ~50,000 miles. When I try to get some quick accelerating, for example when trying to pass someone, the car kinda stumbles a bunch. It doesn't do it in normal, easy acceleration, say from a red light, but when i'm trying to pass, or maybe pulling out into traffic and need to get up to speed quickly. Any ideas?

FYI, I know I have a bad O2 sensor. Could that be it?

 

[Virtus_Probi]

I'm not sure if the O2 sensor would do that, but I do know that I had somewhat similar symptoms when my MAF sensor was fouled.
Pretty easy on most vehicles to unscrew that sensor and clean it off (I bought something just for that purpose from CRC), might be worth trying it before you deal with the O2 sensor.

 

[Jason_Michaels]

If the car has a fuel filter, it may be time to replace it.

 

[Chris142]

Spark plugs.

 

[clinebarger]

What DTC's (codes) are stored in the ECM?

 

[mclasser]

Might need a tuneup.

 

[irad]

Can be O2 sensor. Other things are an ignition coil or mass air flow sensor. You can clean the maf, but to remove it you need anti-tamper torx bits. Clean with a non chlorine spray; brake pad cleaner, maf cleaner or carb/throttle body cleaner.

 

[WyrTwister]

Air filter & intake piping OO ?

Exhaust system OK ?

Can you check fuel pressure ?

 

[KalapanaBlack]

My money goes on intake air hose. Especially if it bogs/stumbles in low-speed, high-torque situations (accelerating from a stop uphill).

 

[meep]

First thing I'd check is all high-tension circuits - ie, plugs, wire, coil, and dizzy if it has one. This is a classic arcing scenario. a way you can test this is to manually hold it in a lower gear - this symptom will be much less under higher rpms when the air/fuel mix is less dense, requiring less voltage for the spark to jump the gap. Don't throw any parts at it until you check this first.