Car falls on its face when cold

[The_Ghost]

Hoping someone here can help me. I have an '08 Solstice GXP. I have Solo Race exhaust, high flow cat and a CAI. I also have a tune, but don't know who or what tune I have. It's not GMPP....I do know that. My issue is this, when my car is cold (<150 degrees roughly) it falls flat on its face when I go 1/2 throttle or more. The boost does go up to 20psi at that point, but the revs won't really go past 3000. Is this a safety feature in the tune? Am I having some sort of internal issues? Like no compression in the engine until it gets warmer? I also noticed that the exhaust does get loud so the boost is coming out the back I would assume. Is this something I'm going to have to live with?? I live in MI and planned on driving it in the winter on nicer days....but if its going to act up like this, I can't take a chance. I can't even pull out in traffic when its cold for fear it won't go! Any help is appreciated!

[Iam Broke]

Not really designed to get into boost until it's warmed up but I'm sure your tune can be improved upon. Does it accell ok at 5-10 lbs boost at 150*?

Check the plugs if more than 10k on them. Make sure they are the stock AC Delco's 41-108 or NGK 5476.

[The_Ghost]

Its fine after 140, 150 degrees. It does have the Solo Race exhaust and a high flow cat so it tends to snap, crackle and pop a little more until its fully warmed up! LOL.... It's just that initial first 5-10 minutes of driving where I don't dare pull out in front of anyone, and I don't want to let it warm up for 10 minutes with gas prices as expensive as they've been! Especially burning premium....LOL. So why would the DIC show 21psi of boost when I get on it and its cold if its not supposed to produce boost until it warms up? I will look at the plugs and see what I have...

[ovenroastedlnf]

You do know, you would probably save more gas (or at least use just as much) letting your car warm up then you would running it cold? A warm engine is more efficient than a cold engine. And if gas is that expensive to where you cant afford to warm your car up properly, then your in the wrong game here lol

I'm not trying to be a dick here, just saying let the car warm up properly and you won't have to worry about this!

[The_Ghost]

I know on the gas price thing.... I was just being funny.... So this "issue" that I think I'm having isn't an issue at all? It's normal? If it's normal, that's fine. Then I won't worry about it. I'm new to the turbo game again. I haven't had one in about 15 years....

[Iam Broke]

Check the plugs.

[Wangspeed]

Check for codes. Betting there is a boost leak if you see boost hit 5psi, hang for a sec, and then go up. Or you have poorly wired/dirty (T)MAP sensors.

[stromboli86]

I only got on my car once when it was cold and tuned(also had crimped tMap's at the time)... It did not like it to say the least. Everyone has their own opinion on how to let a car warm up in the morning. I start my car in the morning, turn whatever lights i need on, plug my ipod in and then im on my way to work.

[Iam Broke]

^^^ Me too, but even pulling out onto the state highway from my driveway, I stayed outta boost until it was 180* or so.

[The_Ghost]

I never said the car hung at 5psi and then went full boost. It goes full boost (21psi) when I get on it...there is no hang. I get full boost but it's like it hits a brick wall at 3000rpm and won't go any further even though I have 21psi of boost. You can hear the boost coming out of the exhaust, the car just won't go!!! And it is the exhaust because I have Solo Race exhaust....The only history of a code would be the O2 sensor when (whoever did it) put the high flow cat on it.... And they are the original factory (T)MAP sensors..... I've been very busy and will check the plugs tomorrow night and see what they look like....

Too be honest, it feels like it opens the blow off valve....

[stromboli86]

can you post a log of when this happens? every now and then my car will be a little rich on tip-in and you can feel the car lose power, also i here a noticeable change in exhaust tone at that point. That would be my guess as far as what you are experiencing, cars cold, boost goes up but it is bogging because its pig rich

[gn2beatu]

Keep in mind when an engine is cold, there are fuel multipliers for OL operation. So say for instance you have 14.7 for stoich, then 11.4 for boost when its warm. If the engine is cold, and is adding another 20% due to temp issues, then you probably in the 9's for AFR, which is way too rich. Since you didnt mention a wideband, Im assuming you dont have one, but if you do, what does it say when this happens?

[The_Ghost]

Finally had a chance to pull a plug and look at it. It is a 41-108 AC Delco. It looks fine.... The tip is really thin compared to that of my Mustangs! But the tip is there and everything looked good on it. The car only has 42k on it.... Any other suggestions?

[|V3nom|]

Since you didnt mention a wideband, Im assuming you dont have one, but if you do, what does it say when this happens?

the lnf comes with a wideband from the factory.

[|V3nom|]

Finally had a chance to pull a plug and look at it. It is a 41-108 AC Delco. It looks fine.... The tip is really thin compared to that of my Mustangs! But the tip is there and everything looked good on it. The car only has 42k on it.... Any other suggestions?

does it only fall on its face when its cold?

[The_Ghost]

Yes, it only does it when it's cold. And its usually the first time I get on it when it's cold. If I rev it a few times after it's been running for a couple of minutes (less then 150 degrees) it's usually okay. If I don't and I accelerate hard it just bogs right down when it gets into boost and accelerates worse then with no boost. But after that first time, it's generally okay. It does pop a lot louder between shifts until it gets above 150.

Also if I'm sitting in traffic and not going anywhere fast (like rush hour) when its up to normal operating temp, it tends to "load up" after several minutes. It doesn't flood, but it does start to idle rough until I rev it up.

[|V3nom|]

just seems to me like you need to let it warm up. you shouldnt try to go wot without it being warmed up a little since the oil isnt protecting as much as it can.

[cobaltssoverbooster]

i have a lhu swapped cobalt ss so i dont have to woory about the long period of no boost. it has extra sensors the lnf doesnt have and im verry sure the one in my oil pan helps it boost faster after start. i left it off on accident one day and it took forever like a lnf ecu does 3-5 min after start. soon as i plugged it back in she was boostin only a minute or two after start. 8) its nice having a lhu