Shackleford

iTrader: (12)

Here lately, after I would go somewhere then get back in the car, as soon as I would take off, while in the lower RPMs, the car would feel really weak then all of a sudden hit the RPMs hard and take off normally. Tonight on the way to class, it did the same thing but felt like it was going to die. Just before I got it, I pressed the accelerator down a little, but the RPMs weren't really doing anything. The car just felt like it lost power for a few seconds. So, I just let it do its thing for a few seconds; then after that the car would drive just fine.

What could be the problem? Clogged cats maybe? I hope so, because that will give me the perfect excuse to get some new Magnaflow high-flows finally. lol.

NBM-LS1

iTrader: (7)

Eh sounds like it could be your o2 sensors. So you push on the pedal and it doesnt do anything then you push a bit more and it jolts? Thats what happend when my o2s were bad.

Shackleford

iTrader: (12)

Yeah, that's about right. It only does it like right after I start the car back up from going inside the store or whatever. After a few seconds, the car is fine. It does have 128K on it, so it's probably time to replace them. Crap. I know they're expensive, too. How many do I have and where?

NBM-LS1

iTrader: (7)

There are 2 on each side. two before the cats and 2 after. You might only need to replace one. Any codes showing?

Shackleford

iTrader: (12)

No codes. I was expecting some, though.

NBM-LS1

iTrader: (7)

Switch out the fronts with the backs.Take out the fronts, take out the backs, put backs in front, put fronts in back but dont plug in. (just there to plug the bung)

So what happens from there. Drive it a few times and see what happens.

Omec

iTrader: (2)

honestly if it were up stream o2's you would get a code. and i dont think down streams will work for for the up streams or maybe they will not sure. i would look at simple things like possibly sea foming, fuel filter, air filter and the like before condemming anything expensive. also try cleaning the MAF (kinda what im leaning towards) and throttle body.

Shackleford

iTrader: (12)

Yeah. I sea foamed the gas tank recently. The air filter should be good as I put in a lid a few months ago, too, but I'll check it again. I'll go ahead and buy a new fuel filter. They're not too expensive.

Rushin

iTrader: (18)

It could be a vacuum leak.

Shackleford

iTrader: (12)

Where? I could I find that?

Rushin

iTrader: (18)

Basically inspect all the vacuum hoses running around your intake and throttle body. Any kind of hole will do it. Also check you brake booster vacuum line.

Shackleford

iTrader: (12)

10-4. You don't think it's a clogged cat or two?

Rushin

iTrader: (18)

Doesn't sound like it. If they were clogged, the car would run like **** the majority of the time, not just for that brief moment.

98Z28MASS

iTrader: (6)

Check your spark plugs too, you might have one or more a little lose? Although I didnt have the exact same symptoms after I did my header install when I was at idle at a light my rpms would fluctuate as if it were going to stall and it ended up being that my spark plugs had losened a little. Also check to make sure your plug wires are on tight.

Shackleford

iTrader: (12)

We put all new plugs and wires on a couple months ago. They should be good. I'll check, though.

Shackleford

iTrader: (12)

Some other guys say it's probably the front oxygen sensors. So I would assume pre-cat. What are the good brands at the stores?

98Z28MASS

iTrader: (6)

I believe Bosch 02 sensors are pretty good and are available at most parts stores.

Shackleford

iTrader: (12)

Ok. I'll check out the prices. Where exactly are the two front oxygen sensors?

http://oxygengeek.com/RenderScriptTe...tid=oxygengeek

Red96TA

iTrader: (14)

sounds to me like something to do with plug wires. my car did this **** a couple months ago after header install because some of my plug wires werent properly seated on the coils. also if you have washed your motor off with a hose/pressure washer, it will get up under the plug wires and pool and take a couple of days to dry off. id start with the plug wires. then clean the MAF. then go to 02's. because if im wrong, you wasted 10 minutes, and have to do what you were going to anyways. if other people are wrong you wasted an hour and a nice chunk of change. no offense to anyone :-)

Shackleford

iTrader: (12)

We changed the plugs and wires a couple months ago. Why it start just now and be fine after a few seconds of acting up? The same goes for the dirty MAF. I put in a lid several months ago. If the MAF needed cleaning then, I would have done it. I'm leaning toward the oxygen sensors, unfortunately.