car stumbles in low rpms when driving

[Zen S14]

My car is a turbo automatic. After some racing today I noticed the car start to stumble at light throttle acceleration at anywhere from 1000 - 1500 rpm range. It also poped once at 3000rpm while going about 50mph. Also the car does not want to accelerate quickly unless I press the gas almost halfway.

What could be the culprit? The lowly automatic dying? Spark issues? Fuel injector? How should I go about finding out the source?

[Destructo]

Try pressing the gas pedal harder.

[IGSDann]

I'm gonna say torque converter... Maybe tranny fluid.

The best way of fixing that is doing the 5 speed swap :bigok:

[ghambino]

WHAT? turbocharged automatic, theres no fun in that, do the manual swap as soon as possible, for the price you'll probably spend to diagnose and fix the problem you could convert to manual instead.

[s13gonwild]

props for the automatic turbo. just wondering if you have checked for a boost leak? that could have been the pop it made at 3k....iono check around see if its an oviouse problem like something coming loose....

[Zen S14]

Actually its quite fun when you run brackets at the drag strip. I have a consistently fast car and with good reaction times I beat more than half of the people I run against.

Could one year old spark plugs be the culprit? I don't think I've changed the spark plug since the car has gone turbo. Its been through about 300+ runs down the quarter mile.

I don't think its boost leak because vacuum is showing -20 to -10 when I have the stumbling. I'll check all connections just in case. The car has been really good until today. One year of turbo with no headaches and no issues.

[Whiplash Willy]

You may want to check the Distributer cap and rotor. I was having similar problems and thoes were shot.

[s13gonwild]

wow...yes get new sparkplugs,along with cap and rotor please LOL

[Zen S14]

Thanks for the tips. The motor has over 150K so I will check the cap and rotor as well. I am going to upgrade the tranny to enhance its ability to handle additional power as well, but I would not want to be forced into it.

Hoping its only the spark related problem. :x:

[Zen S14]

Well, problem solved. It was a cracked number four cyclinder spark plug. A new set of plugs solved the stumbling problem. The tranny seems fine but I'll do a service on it just in case.