When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hey there, just saying hi basically and gonna tell ya lil about my journey with LSJ Cobalts. First off, I will tell ya if you ever see me asking questions. I will have A. Done exstensive research into the question for answers. B. I’m asking because I really just don’t know. C. Looking for personal experiences with the questions I present. This is my second LSJ, I love it even more then the first. There are issues with this car from previous owner neglect; but a dedicated owner and enthusiast (ME) with love, blood, sweat, tears, and a lil bit of pocket change; will bring her back to her former glory and be built out to a nice, daily/street car at the end of the day! 06 SS/SC, mods: injen intake (horrible), ebay 2.5 full exhaust system (horrible), B&M short throw (not bad), lowering springs (horrible), EBay Headlights, and supposedly a new fuel pump (can hear it, so I know it works atleast). All mods were done by previous owner, a long with all the problems that have come to my acknowledgment. Let’s dive in: down stream O2 is not even hooked up due to wiring coming out of O2 (just found out 2 days ago), an exhaust stud is broke off, exhaust manifold gasket is leaking, the intake tube is beat to hell and I’m sure has a leak in it (piping was loose), no MAF hooked up, a hole in the intake coupler to the TB (duct tape is what keeps it shut), TB is shot (have tried cleaning and still persists), intake manifold gasket has started leaking, IC Pump is faulting in & out, heat exchanger leaks at bleeding nipple on top, bad ball joint driver side, (replaced and 4 new tires), rear calipers have started to leak, AC blows but not cold (Compressor is what I’m told), a million and one vacuum leaks from dry rotted lines (salvaged every inch I could, zip ties around conjunctions, and I’ve managed to restore 17hg of vacuum which is almost there; few minor things still), I’m thinking either my clutch is going or TOB is... (if I rev car out, I lose pressure most times, sometimes it gains hella pressure and is slapping me back in the face; any insight would be appreciated) EVAP solenoid has failed (bypassed for now), fuses (think I’ve replaced almost all of em), relays, some wiring issues that I’ve managed to work out (praying for no more hidden treasures), clutch pressure switch, the linkage in shifter was a hair off causing my 5th gear to be on outside of lockout wall (adjusted and now is fine), 17 codes were being thrown at time of delivery. And that was discovered upon finally getting coolant back in her (ran dry or sat too long and it all evaporated), oil was changed due to being a white sludge, and white smoke pouring out the back end (head gasket issue I assumed). Did an oil change. Put some BARS Head Gasket Sealer in with the first round of coolant, let it sit for a day, flushed it and put new coolant in. Replaced plugs, and BADDA BOOM BADDA BANG BABY! Cars running, no smoke, no oil burning, no coolant burning, no leaking of either, car was driveable enough to get to autozone. Car runs on a closed loop from my understanding with no MAF nor downstream O2, no way for it to monitor AFR, intake temps are prob running a lil high considering the IC pump and heat exchanger, car runs rich but not like pig rich or anything, suspension components suck but hold now and my steering wheel is straight again after a nice alignment. My goal is to repair her back to factory spec of health, then tastefully mod the M62 set up out to 300hp, then move on up to TVS and go with F40 trans and shoot for 400, then maybe later do a turbo swap, maybe go twincharged, or just have ZZP build me a race ready block that I can just swap in and out and go track racing. I enjoy the build process and want to see this time around what all the LSJ really has to offer. Stay posted, I’ll keep up to date with the car as I go. I’m like a kid in a candy store living on a cupcake mountain, with caramel rivers below me flowing so beautifully. Haha lata gents, and pleasure to be here.
-Austin
Welcome to CSS.net Sounds like your car was ridden hard and put away wet by the previous owner. Way the oil and coolant was I would recommend doing a compression test just to make sure the engine didn't get hurt before pouring too much money into it. Like you said first order of business is repairing all the faults that are causing drivability issues and tripping your CEL. First thing I would rectify would be the MAF sensor. I'm surprised you can even drive the thing without a MAF plugged in.
Once you start to tear into it, document your process on here and we will be able to better lend assistance along the way. One other thing I can recommend is prioritize your repairs while also considering what is easy to replace at the same time.
Sure looks nice from the outside considering the amount of abuse and disregard that the powertrain has experienced.
Thank you for the reply and insight. It’s holding compression to my knowledge; only time it stutters out is stopping and upon start ups (hope just replacing the TB will solve this issue since cleaning hasn’t), a test wouldn’t hurt to see for sure tho. If anything big is hurt, I’d assume the head being warped if anything. I agree it’s amazig the car starts and runs phenomenal considering all of the issues it has. True work of wonder! I have full boost at WOT, only a pound will disappear here and there. I will check back regularly as it moves forward more and I dive deeper into it. So here’s my priorities for car as it stands right now.
1. Compression test
2. Pull codes again
3. Replace IC pump & H/E *OEM and ZZP*
4. Replace EVAP Purge Solenoid (possibly the purge valve and canister also)
5. Replace both O2’s, and incorporate a wide band to monitor AFR (gotta look into a lil more)
6. Replace MAF and MAP sensors *OEM, and OEM SCIP, TMAP, barometric*
7. Replace CAI *ZZP 3”*
8. Replace TB *ZZP LS4*
9. Replace exhaust *ZZP Midlength header and exhaust combo 3”*
10. Replace all gaskets except for head (unless need be) *ZZP*
11. Replace vacuum lines (found a set of precut ones, thought about just grabbing a couple feet and cutting down to size myself)
12. Replace cooling lines (if need be; all hold right now)
13. Transmission worked over (need insight when that time arrives)
14. Whole suspension and brake system worked over *better springs or coils, control arms, axles, wheel bearings, big brake kit all the way around, master cylinder, brake lines*
**if all is going well at this point in saving the car and has fixed my issues; I’ll grab a PCM update from ZZP, or go to someone for tuning to atleast run top notch (all issues should be worked out hopefully)**
15. Lighting (headlights, tail lights, fogs, interior all LED)
16. Body work (She’s dented everywhere, clear coat fading in places too) *will replace any body panels that are not able to be fixed, will do carbon hood and trunk here*
17. Remachine the LSJ wheels and have em re sprayed in black chrome (want to grab an LNF SET TOO)
18. Enjoy her at a starting point of a solid car
19. Then start going for power
SIDENOTE: I figured I would grab the few upgraded parts along way so I’m killing two birds with one stones throw. Considering they really aren’t that much more then just OEM parts.
I would bump the MAF up to ahead of IC pump and H/E. I wouldn't even drive the thing until you have a functioning MAF sensor and damn sure wouldn't be going into boost. Intake air temps aren't that big of deal until you are boosting anyway. Without the MAF though your ECU is going to have a hard time guessing how much fuel to dump without being able to monitor airflow and it's just not a good idea to run it without it. Then I would get the O2 sensor replaced. Also MAP sensor if it isn't functioning properly. If it is working right I would just leave it. Fueling is way more important than cool intake temps.
Your throttle body may be fine. It could just be running like crap because of no MAF sensor. Also if you go to LS4 TB it will hinder the drivability and you will also need a tune for it to even work right. LS4 TB is more like an on off switch and gives you much less precise throttle control. Good for drag racing but that is about it.
See the thing is tho, I’ve replaced the MAF once, fixed it for 2-3 weeks, car will not run with MAF hooked up as of this time in life. It will run for 2-3 mins if connected and go into limp mode. Yes, I would agree; it along with the O2’s being replaced would be beneficial first. Only issue being I’m not sure if once I hook them up, they throw the car into limp mode because AFR; Yeah it would stabilize at its Intended levels, TB being shot tho as well will continue to not allow proper stabilizing of it though. EVAP as well and now that I’m thinking I should prob do a smoke test on the EVAP system once I do replace the solenoid. It’s bypassed right now, but there’s my fuel aspect of AFR. It’s a mess man. Idk if there’s a tune on the car that’s allowing it to run right now, I have full power band, normal coolant temps as far as I can monitor, runs a lil rich but nothing serious. As for the LS4, I’ve planned on running the OEM one as long as it’ll last for now, regularly cleaning, get the vacuum aspect all prepped for a single day of labor, get the fuel aspect prepped for the next, and cooling aspect sometime in between. It’s all gonna be thought out in debth As whole projects to make sure I cover everything. I’ll just grab an OEM TB for now in mean time. So for starters: Intake coupler, MAF, O2’s, TB, EVAP solenoid. and IF PCM is flashed factory still or is flashed to factory spec; I should see improvement in car. Vacuum lines being replaced as just a preventive maintenance deal so I don’t have to worry later. My idle for vacuum is right where it should be according to gauge on pillar. I know my STFT AND LTFT’s are prob not right consider of EVAP bypass. Question tho? Would you agree the gaskets for Intake & Exhaust, also valve cover gasket (forgot to mention one stud is also broke on valve cover) considering they would allow for unaccounted air.... Its cooler this week temp wise where I’m at in OK, since it’s cooling down, should I be okay staying out of boost and not having to worry to much about hurting the motor furthermore then what might be hurt? I have to drive it considering life has made it my DD. Life happens tho ya know? I really don’t get on it ever because of the problems, it’s taken me almost 9 years to finally be able to get another one. Definitely don’t want to destroy my baby, but if she ends up giving out, I’ll just end up doing a heart transplant. Im about to go pull codes, will post pics of motor and all it’s crazy shenanigans, along with video of startup and driving. Just wanna get her healthy again and back up tip top shape so I can really enjoy the car to it’s fullest.
Another thing when it comes to tuning... if need be; because who knows honestly how she is going to run with parts finally being repaired, and replaced if.... IF... Major IF HERE! If the PCM does have some wacky tune on it that runs almost similar to factory parameters but has been tweaked for car to run; can I just simply reflash it, or would it be best to get all the equipment for monitoring the car as well and go with HPTuners and have someone do I guess “real time” tuning on car instead of running off pre files. Say the car reacts fine to the repairs tho in opposite; would a reflash just be needed then to have stored memory codes wiped so it all resets and functions together properly?
See the thing is tho, I’ve replaced the MAF once, fixed it for 2-3 weeks, car will not run with MAF hooked up as of this time in life. It will run for 2-3 mins if connected and go into limp mode. Yes, I would agree; it along with the O2’s being replaced would be beneficial first. Only issue being I’m not sure if once I hook them up, they throw the car into limp mode because AFR; Yeah it would stabilize at its Intended levels, TB being shot tho as well will continue to not allow proper stabilizing of it though. EVAP as well and now that I’m thinking I should prob do a smoke test on the EVAP system once I do replace the solenoid. It’s bypassed right now, but there’s my fuel aspect of AFR. It’s a mess man. Idk if there’s a tune on the car that’s allowing it to run right now, I have full power band, normal coolant temps as far as I can monitor, runs a lil rich but nothing serious. As for the LS4, I’ve planned on running the OEM one as long as it’ll last for now, regularly cleaning, get the vacuum aspect all prepped for a single day of labor, get the fuel aspect prepped for the next, and cooling aspect sometime in between. It’s all gonna be thought out in debth As whole projects to make sure I cover everything. I’ll just grab an OEM TB for now in mean time. So for starters: Intake coupler, MAF, O2’s, TB, EVAP solenoid. and IF PCM is flashed factory still or is flashed to factory spec; I should see improvement in car. Vacuum lines being replaced as just a preventive maintenance deal so I don’t have to worry later. My idle for vacuum is right where it should be according to gauge on pillar. I know my STFT AND LTFT’s are prob not right consider of EVAP bypass. Question tho? Would you agree the gaskets for Intake & Exhaust, also valve cover gasket (forgot to mention one stud is also broke on valve cover) considering they would allow for unaccounted air.... Its cooler this week temp wise where I’m at in OK, since it’s cooling down, should I be okay staying out of boost and not having to worry to much about hurting the motor furthermore then what might be hurt? I have to drive it considering life has made it my DD. Life happens tho ya know? I really don’t get on it ever because of the problems, it’s taken me almost 9 years to finally be able to get another one. Definitely don’t want to destroy my baby, but if she ends up giving out, I’ll just end up doing a heart transplant. Im about to go pull codes, will post pics of motor and all it’s crazy shenanigans, along with video of startup and driving. Just wanna get her healthy again and back up tip top shape so I can really enjoy the car to it’s fullest.
Unless you think the intake manifold has been removed I would not suspect you have a bad IM gasket. I would leave that, exhaust and valve cover (unless oil is leaking out) gasket alone for now. Honestly, if I were in your shoes the very first thing I would do is make sure everything is returned to stock before trying to diagnose anything. Mainly pulley, injectors, intake and tune. That way you can rule out an incorrectly configured tune. Your car is going into limp mode because something is so far out of whack it is trying to protect itself. Your MAF probably isn't the actual problem. A good start would also be to share your engine codes but with that many there is most likely a number of things that need rectified and until you eliminate variables like a wrong tune it will be very difficult to troubleshoot.
I concur man. I’m getting codes ran right now at autozone just to see.... again.... I know there’s gonna be a lot. As far as reflashing the PCM and making sure it’s back at factory parameters, I will do once I can get the lil first things like MAF, O2’s, Coupler, TB, MAPs, and EVAP to atleast have basic components working again that are attributable to the problem. I’ll finish replacing the relays for everything along with fuses, and vacuum lines as a precautionary measure and peace of mind. And I’ll go from there at that point. Intake manifold gasket I suspect is shot because under WOT, dipstick pops up and shoots oil everywhere under hood. Have read that tends to be the culprit. A big mess. Should it be zip tied shut, NO NOT AT ALL. Temp solution to just make sure I’m not losing oil out of it if it does pop up under mild throttle situations like merging or passing. I will post the codes, I’m seeing show up, can prob find another enthusiast with a scanner and have him run them too. I have a walk around video of car to show you the essentials of problems (whole shin dig honestly) the infamous plug of MAF and the MAF Sensor sitting in the intake tubing, along with start up and running at idle (on cluster, at exhaust, and at motor) with an aggressive rev as well to hear it. I did forget to get the upstream O2 in it and the two studs broken (valve cover and exhaust). Did find a interesting discovery with downstream O2, I’ll let ya see for yourself, maybe help me out with why?!!?!? And a lil moderate drive video. Welcome to the weird occurances that I go through and am amazed daily by this car. How do I go about posting these videos here so y’all can see?
Usually to post videos you'd upload to youtube or something and then post the link and it will embed. Also dipstick flying out under WOT is a sign of massive blowby or a clogged/plugged breather port on your valve cover. Is your breather port on your valve cover plugged off? It should be a little nipple sticking out that has a hose connected to it that routes over to your intake tube.
And yessir it goes into limp mode as a fail safe; but what’s weird is it only goes into limp mode when MAF is connected. Only thing I can just ponder on is something along lines of the tune. Won’t know till time comes to bandaid. And here are the codes being thrown, this car started with 17, I will try and find paper that had that many on it; I am now down to 4.
P0102 MAF Sensor circuit low frequency
P0036 HO2S Hester Control circuit sensor
P0443 EVAP Purge solenoid Control circuit
P0068 Throttle Body airflow performance
soooooo another new MAF, I’ll clean the intake filter again as well, O2’s, will see if replacing the coupler from intake to TB fixes that issue before replacing the TB itself, new vacuum lines (safe measure) and the EVAP purge solenoid and then we see. Should I do the reflash of PCM at this point as well??? I’m just ordering all the parts as a whole group; Chevy dealers can reflash right? Injectors and pulley are stock as far as I can tell, bright green injectors. Pulley I haven’t tried really looking but considering I’m at normal boost levels I’m gonna assume stock pulley. Any indicators to look for without pulling it off?? I know most say on it like the size is engraved into it, if it’s factory will there be anything?
Didn't you say earlier that the coupler between TB and MAF had a hole plugged with tape? Any chance that could be a source of a vacuum leak? Whatever it is doing it sounds like it has no purpose on your setup so I would remove it and see if anything improves. Looks like your ECM might be saying there is a large vacuum leak. With the P0102 combined with P0068.
No, that tube is free flowing like it should be boss. Only things plugged are the EVAP lines.
You try blowing through it? You may have some massive blowby though that should show up on compression test. Is the theory with the intake manifold gasket that boost somehow leaks into the PCV port pushing air into the crankcase?
Compression test will be getting done this weekend when I have the funds to have someone hook it up and see. Will post back results when that’s done. And yes the Intake coupler has a hole that’s been duct taped shut to hold what air it can. Silicone piece never completely detached, so it’s not like a straight hole through but you can pull the piece up and it’s a hole then. I will make sure that hose is observed during compression test. And yes on the theory, I’ve seen people say it could be rings too. So I’m not sure 100%. Was gonna go easier route then address later. I’m cool I’m just dealing with these 4 minor problems first then gonna go from there. Recommend PCM flash at end of day as well?
Someone on here probably knows better than me about how to check if tune is stock or not. I wouldn't say you necessarily need one yet. Have you actually replaced the MAF with a new OEM unit? Is your intake tract modified or stock? Although it could just be that TB spacer plate leaking you need to figure out why the ECU is deciding the airflow is so far off. Tune won't matter if the ECU isn't reading airflow right. I would check for vacuum leaks with some carb cleaner. Spray it around suspect areas and listen for change in idle characteristics. If you spray somewhere and the idle rpm modulates at the same time you have discovered a vacuum leak.
Vacuum leaks are all accounted for, considering the downstream O2 helps with AFR, that with another new MAF that works with O2 for AFR, MAF tables are prob way out, STFT and LTFT are not proper due to EVAP, TB is failing from neglect of last owner or like you said it could be just cause the MAF isn’t being read since it’s unplugged and intake, EVAP same thing with plugged lines as well, gotta be affecting in some sense with fuel since vapors trapped in tank are now not venting. Looking at the TB code in more debth... it’s for airflow performance, I bet you are right that the coupler is causing that issue, along with no MAF since it’s not detecting airflow; as far as Intake tubing goes, it’s an Injen CAI, that’s been beat to hell hence why I’m replacing with just ZZP’s 3” CAI with new MAF (will come with coupler it states; unless going LS4 TB, which Ima see if this doesn’t fix the TB issue first). So fingers crossed, hopefully compression comes back fine (will install parts needed before test) and if all is good; Call it a day and move on to more mechanical aspects that are needing or will need to be replaced. I greatly appreciate you going in debth with these last Lil issues (hopefully) and helping me with things. I’ll check the intake gasket when I get to doing the IC Pump because I want to pull the intake itself and do spacer plate for the SC, phenolic gasket, dual pass endplate with option B, bigger H/E, oversized radiator. It’s HOT in OK most days. Haha should fix my A/C sometime too and maybe some tint would help out. Again man, I greatly appreciate all the feedback. I’ll figure out the dipstick thing one of these days, get back with my findings. Will report back after parts are installed and figure out what’s going on. And will just keep updates on the whole progress. I wanna be able to share my pride and joy with the good people who help along the way, let them know that they had a helping hand one way or another, and maybe even inspire someone to just say I can do this, just gotta want to do it.
