misfiring
 

ok ive been having this problem for a while. my cobalt is misfiring but heres the catch. it only misfires when it rains. if its dry out than my cobalt runs like a champ, but when it rains, the car wont idle right and the vacuum goes all the way down to 0 than either stalls or jumps up to like 3000 rpms than goes back down and does the same thing. idk if it has to do with the the injen intake that i have or if water is getting in somewhere or what. help please guys, thanks

07 cobalt ss/sc,,injen intake,,vibrant headers and downpipe combo,,

Check to see if the ECM connectors are well seated and sealed. I have heard of another vehicle with similar issues that had a seal issue on the ECM connector and water would get into the connector and cause issues.

Whens the last time you cleaned and oiled the filter on the injen,it might be dry and not repeling the moisture anymore and causing a issue.
Another thing buy yourself some di-electric grease and start pulling connectors and resealing them by applying the di-electric grease to the pins etc.

Also look for a coil pack grounding itself.

Is it possible the filter is passing too much moisture and allowing the MAF to get wet? I would put the hydro-shield on the filter and see if that helps.

Put a hydroshield on your injen

where are the ecm connectors located? and i put the injen on about 2 years ago and i havent really messed with it yet so that could be the problem

For the injen buy the recharge kit,comes with a solvent for removing the old oil and dirt as well as the oil to make it like new again.
Just dont over due the oil and create other maf provlems.A light pink color is good enogh of you do it on a regular basis.
2 yeaes is a bit much,I do mine every spring and late fall.

Ecm is located on you right when looking under the hood in front of the fuse box( its incased in Aluminum)

ive tried everything. it wont idle right. it keeps going from 2000 rpms to 600 rpms a couple times before it stalls out. i think i may be screwed...

Try this
https://www.cobaltss.net/forums/2-0l...inally-116051/

That is a good solution while I also have to do. But however, he could still drive his car. I am unable to even pull down the street without the car misfiring and violently jerking back and fourth. I think it may be my o2 sensor but would that really cause all this problems?

If the idle problem is there when you first start it in the morning it wont be the O2 sensor,im pretty sure the car ignores the O2 sensor until it warms up and runs off of the maf sensor and set tables in the ecm.
If you suspect the sensor unplug it and the car will run in closed loop and ignore the sensors.if it idles fine then there is most likely a sensor issue.

Did you pull the plugs yet,are the fouled(carboned up)?If so clean them.
Or are the flooded with fuel?(dripping with gas)

Clean the throttle body if you havent yet as well.

ok. and the maf is the sensor located in the intake right?
and just changed the plugs like 2 or 3 weeks ago to the iridium plugs so i should be good on that
have so many problems with mine. im leaking fuel everywhere from the fuel pump but i think i read that thats under warranty but idk i gotta check a lot of things but the misfire is the main one.

Ok so I'm gonna clean my throttle body and intake today. I know I should use throttle body cleaner for that but what should I use for the intake and how should I go about cleaning it?

My problem is somewhat like this...my car seems to misfire in the morning regardless of the temp outside. It clears itself up after about two minutes of the car running..i have performed a compression test to see if there are internal problems with the engine.also replaced ignition coil,plugs and ignition module on top of coil pack...
Changed all o2 sensors...any other suggestions would be great..