I know what the problem is, but I already stated my opinion up top.

You should have waited til I was around.
Also double check your harness connection to the TB, sometime it's not fully engaged and will throw the car into limp mode.

 

Checked it, it's connected. The problem happened before the car was tuned so I know it's not the tune. I think the TPS is faulty.

Made an appointment with the dealer for Friday. They told me they need the car all day to get it right. Great. Also told me I need an injector cleaning service every 15k Get the **** outta here. Anyway car goes in Friday and should be covered under warranty. We'll see what happens.

 

I know what the problem is, go back to your tuner and hopefully he realizes the mistake.
also double check and make sure you have no vacuum leaks.

 

How is it the tuner if the car did this prior to being tuned? I had the crankshaft re-learn done, but the issue is still there. It is throwing a p0121 code iirc, something to do with the throttle position sensor. I am certain I have no vacuum leaks, I doublechecked and triplechecked all of my connections. Also, when the code comes up and power is reduced, the car fixes itself if I jiggle the plug around that sits under the TB. I also noticed the gray plastic clip is broken off of that plug. Is it possible that the plug isn't in there all the way, so when the car is wide open the computer freaks out from low voltage and cuts the power?

Car goes to the dealer friday but I would rather not bring it in if it is something simple that can be fixed.

Going to try zip tying the connector on tonight since the plastic clip is broken off. I'll update on this later.

Also thanks paul for giving me the heads up about the p0068 code. I'll talk to who tuned my car and see if he changed the value to 8000.

 

yeah didn't know the clip was broken til I just spoke to you, but I'm almost 100% positive that it's that, just grab some zipties and that should do the trick

 

Zip tied cobalt FTW

Sitting at work until 8 FTL.

Got the CEL and reduced power again.. I didn't have a chance to zip tie it on though. Does anyone know if I could get the clip for the connector somewhere? It's fine during normal driving but as soon as you get high in the RPM's and put your foot down it's game over.

 

chances are without buying a new connector or finding a wrecked cobalt in your area to take the sensor out of i don't think you can just buy the clip.

 

The clip's been broken off ever since I did the silencer holes and it was fine then. It started after I put the 3.0" pulley on and reinstalled the SC. But I am almost positive its something to do with it since the CEL goes away if I disconnect the batt and jiggle the wire around. THen it comes back during hard driving and goes into reduced power mode. I don't think the dealer will know what they are doing with it.

Anyone? I don't think I am going to take it to the dealer, be a big waste of time IMO.

Just took it for a drive. I jiggled the connection around but didnt unplug the battery, and the reduced power didn't come on. but the CEL did. I drove it normally, and nothing. As soon as I got onto the throttle a little harder than normal it hit reduced engine power. THIS IS PISSING ME OFF TO NO END. I have a stage 2 + car yet I can't floor it! USELESS!!!!!!

bumpp

 

bump for today.. drove to work with the thing in limp mode

 

Zip tie the damn thing.....

 

I ran out of zip ties

I'm buying the clip from a member here. Hopefully that will take care of the issue...

I just jacked some big ass metal industrial strenth ties from work. If these don't hold the connector in place then idk what will..

 

well i hope it is the clip. today my brother who owns a stage 2.5 cobalt ss/sc had to drive his in limp mode as well. but we got a nice little handy portable code scanner so every 3 minutes he was clearin the codes. he might be having the same issues as you.

 

Is his an 07? Just curious...

I used that metal tie thing I got from work.. I didn't get on it too hard but I did go wide open for a few short bursts and it didn't kick into limp mode. I can only hope this is the problem... *crosses fingers*

 

no his is an 06 i'f im not mistaken but the funny thing is the same thing he just started having problems. you know the car is screwed up when a more or less stock 2.4 takes a stage 2.5 ss/sc off a light, i beat him by like half a nose. and he's also a damn good driver. we all had a good laugh about it at the club.

 

damn, my car has never once ever gone into limp mode...odd

 

It's definitely that stupid connector, at least on my car. I was hammering on it for a while and it was fine.. WOT in 2nd, 3rd.. took it to 100 at WOT. I went 1-2 hard and it kept going, hit redline in 2nd and BAM.. engine power reduced I guess the connector must have came a tiny bit loose again. Thing is very sensitive. Tightened it back up and it's been OK so far.

 

ya definetly sounds like its your connector causing this. i know my bro still hasn't figured what is causing his. but he's a mechanic and with all the other techs we have at the shop it shouldn't be too hard.

 

Yeah. I can't believe how much more ***** the car has now over stock. It's amazing.. low-midrange is GREATLY improved. IT actually pulls now in low RPMS as opposed to kind of just bogging out. Oh, and that blower scream is something else.

 

ya i wish. i've got the ss/na and right now its been acting really weird. likes to jerk when i let off the gas, running a little rich, misfires on 2 and 3, maf going all weird, and hesitation, as well as i'm pretty sure something is grounding out my A/C cuz my a/c relay command is initiated when i the hvac is in the floor position.

 

I hate how every new car is so computer controlled.. all it takes is 1 little sensor to be slightly off (or loose.. lol) and the whole car goes haywire. I want my 88Z24 back!!!!

 

ya i made a thread in the problems section for some fresh idea's above what i've tried already. and from what i've tried already everything seems to be dead on

 

Yeah. Mine's definitely that stupid connector. Did some WOT pulls and it's been fine. Swizzie!!

 

nice. now just get that new connector and your golden.

 

I have seen some problems with the TB on 2.2/2.4 but not that many on the 2.0 but there's not that many around here and that gray clip is made to keep the connector engaged during hard driving so I would say that is the problem but what do I know I'm only a GM master tech And you guy's hate dealerships so much I must be the spawn of the devil and if you don't think you need an injector flush take off your injectors and look at the valves are they cover in deposits if yes a GM top engine clean will clean that crap off if there not than a bottle of fuel system cleaner will keep them clean

 

ya thats my next step is a fuel system clean. and i work at a chevy dealer in the shop myself (just waiting for my apprenticeship at the moment). if after the fuel cleaner its still doing it, then i'm gonna try carb cleaner and throw in a crankcase cleaner as well. and if that don't work then i'm waiting for our really good driveability tech to get back from vacation and consulting with him. also listed in my thread is what i've tried so far to no avail.