Today I installed a k&n filter in my stock air box with the lid re-installed
When i do a second gear / third gear pull, my car seems to hesitate between 2000 and 4000rpm

feels like it pulls then lets off then pulls.....not that exagerated but you get the picture

any ideas?

 

My car is 100% stock and it has that very hesitation. Told the dealer like 4 times and they "can never reproduce the problem". My guess is intake leaks (since you were just messing with the intake) or the MAF sensor is f'ed for some reason. Another possibility I considered on my own car is fuel pump/injector problems (eg. clogged/dying/whatever...) I'm hoping Stage 2 will fix it.

 

anyone else? 700 miles on the car

 

Disconnect the battery, mine ran really fu*ked up after installing the K&N filter until I did.

 

Disconnect the battery and wait five or ten minutes and hook it back up.

 

when i put on my jbp intake the car ran like poo, sounded like it was backfiring, sputtering, and delay in throttle, i disconnected the negative terminal on the battery for 30 min, hooked it back up and now no probs and she friken rips

 

ahhhh ok...i didnt think that would matter for just a drop in ...thanks

BTW....when i bought the car i was wondering why under the hood looked a little bare....didnt realize the battery was in the trunk LOL

 

hey guys,i had idle and rough running probs after installing a k/n drop in,eventually it kicked off a code/service engine light,i brought it to my saturn[04 ion r/l] dealer just yesterday,apparently therre is a technical service bulletin for this problem....my throttle body was replaced per tsb instructions......wow,i suddenly have my prob fixed!...theres a lot to be said for waiting until the warrenty expires to modify your car.the dealer said if there were non gm performance mods the throttle body would have cost me about 350 bucks!..im sure that the tsb applies to the cobalt ss too. colm

 

They probably just disconnected your battery while installing that and while the battery was disconnected it reset the comp to adjust to the drop-in. AKA. Them being idiots trying to get you not to mod your car!

 

still does it and i let it sit for an hour without the battery

 

ahh..

 

anymore thoughts?

 

Ignition misfire? Check the plugs.

 

i think its a driveby wire issue, some totally stock ss's do it aswell, mine does it once in a while, from vacum to boost is when you see the slight hesitation.

 

The engine will hesitate and stutter when it's not receive all it's air past the air intake sensor.

It sounds like a leak from somewhere, I had a custome made intake installed and it popped off and the car ran like **** cause it wasn't getting ANY air that was passing the sensor first. The car runs but it has trouble and stutters.

I would recheck your work.

Reset the Computer (disconnect battery for 10 mins)

Then try again.

If that doesn't solve it, it could be a spark issue. My Alero did the hesitation thing in 4th and it was because one of my spark plugs wasnt getting proper voltage.

 

well if i shift into 2nd....at first things are normal, then once i hit 3000-3500rpm i get a slight hesitation, then after 4000 its smooth as can be

i will recheck things but i didnt touch anything execpt taking the bottom of the box off

 

the way you shift plays a big roll for these cars too, if you dont slam into second shifts are always smooth, for me the slight hesitaion i have is around 2000 rpms in second then punch it, so starting from a low rpm ofcourse its not gonna feel that responsive and thats the only time it happens when it happens, search hiccups its very common and i persoabnlly think its the drive by wire system, they will are not eyt as respnsive as throttle cables so givin the way you shift you will feel it more depending on what rpm you are in.

 

took the kn filter out and the problem is fixed

but now my sc is too quiet LOL

 

put the kn filter back in (reset the battery) took it for a good rip....and the problem is back

i am thinking i am going to keep the kn filter in until i get my stage 2 in because i am hoping the larger injectors will help

i duno what else it could be

 

ya these engines are silly when it comes to modding the intake lol.

 

no kidding.

what alot of work swapping the filter 3 times

 

well i have the stage 2 in now and it did not fix the problem
everything is installed properly

i duno what else to look at

 

i just put on a 2.85 pulley from zzp and it dosnt do it nearly as much, come to think of it, it hasnt done it all day, im also boostin at around 125 kpa at redline

 

nicee i only get 100-105 at redline

i duno what the hell it is....once i am in second at the lower rpms is fine, then at 3500 i get a hiccup then after 4000 it pulls hard

 

It could be a boost leak, not just an intake leak. If the gasket for the blower is shot you will leak boost. Try this. From a stop gun it through at least 3 gears and keep a close eye on your boost gauge. During acceleration the boost gauge should not be droping down at all. Check that. It's all I can think of right now.