New 02 GTP Anniversary Issues

[02GTPanniversary]

Hey guys, I just bought a mint condition 02 GTP Anniversary, with a new trans/engine. Also told S/c was new as well but I don't believe it, for 5500$. Anyway when I rev up the engine the boost gauge is only showing half boost, same with then I floor it. I have messed with the Boost Bypass Actuator and when I have somebody hold it down, and i rev up the car, the boost guage shows full, Could it be my Actuator causing the reason I do not get full boost? The car does not bog at all or anything when I get on it, I just think it does not get full boost, I feel like it should be faster, Also I have a check engine light that is reason to low of air flow/MAF needs to be cleaned, If I replace my MAF sensor could that help? Thanks guys I really appreciate it.

[kuntzie]

The gauge doesnt read full boost like that, and the car is stock it's proably not that quick

You need a new maf most likely

[02GTPanniversary]

So my boost gauge should only fill up halfway? On other videos it shows it filling up full, and I have had other people tell me it should, and I know Its not that quick lol. But then why would it show full boost when I hold the actuator lever down? I dont think It touches the bottom all the way. And a new sensor or mass air flow itself

[blueguy]

The gauge doesnt read full boost like that, and the car is stock it's proably not that quick

You need a new maf most likely

yes on the MAF...and no on the gauge. If your going by the DIC gauge...even stock it will go all the way up...boosting 7 LEGO's YAY! But if it isn't...most likely the issue is pertained to that MAF sensor OR there is a vacuum leak.

So my boost gauge should only fill up halfway? On other videos it shows it filling up full, and I have had other people tell me it should, and I know Its not that quick lol. But then why would it show full boost when I hold the actuator lever down? I dont think It touches the bottom all the way. And a new sensor or mass air flow itself

You can always go to your local junkyard and yank a new BBV off of a supercharged Series II/III car...they are all the same from '97+. You could also have a vacuum leak...check all of the rubber "T" fittings around the BBV, to the FPR, to the LIM (under the supercharger snout) and back to the MAP sensor...they all tend to dry rot...and I've seen some that don't leak until there is boost applied thoughout the system, but don't appear torn or rotted...

[02GTPanniversary]

Yay okay, yeah I had a fit with the Ts, I had one come off under the map sensor abd couldn't find it lol, I got It though the one under the altenator has a crack in it, but I taped It all up, but gauge is still showing the same, i hope its the mass air flow sensor thats only a 120$ fix.

[02GTPanniversary]

And where can I buy the rubber ts would like to have new ones.

[blueguy]

You can get the vacuum fittings from your local dealership...

[deadcell608]

my car had the same problem, was a bad boost solenoid. cost me 20 bucks from the dealership i work at. gauge would only go up halfway and lack of power. mine had set a p1646 in the pcm which did not turn on the MIL, here is the circuit description from the online service manual, Output Driver Modules (ODMs) are used by the PCM to turn on many of the current-driven devices that are needed to control various engine and Transaxle functions. Each ODM is capable of controlling up to 7 separate outputs by applying ground to the device which the PCM is commanding ON. Unlike the Quad Driver Modules (QDMs) used in prior model years, ODMs have the capability of diagnosing each output circuit individually. DTC P1646 set indicates an improper voltage level has been detected on the output circuit which controls the supercharger Boost Control Solenoid.

[02GTPanniversary]

Holy moly sounds confusing. Can I just get a solenoid and replace that? Lol.

[02GTPanniversary]

Hey when I disconnected the vacuum line to the solenoid I got full boost and was quicker, would it be bad to run with it disconnected till I get a new solenoid ?

[deadcell608]

it wouldnt be bad per say, but fuel economy would suffer. you could do it temporarily but i would recommend replacing the solenoid as soon as possible.

[02GTPanniversary]

By leaving it unplugged, would it suck stuff in?

[deadcell608]

If you're worried about that could could just cap it off.

[02GTPanniversary]

I thought about it, but its a vacuum line so It sucks in. If I cap It off won't the boost not get full potential

[txslow6]

Hey when I disconnected the vacuum line to the solenoid I got full boost and was quicker, would it be bad to run with it disconnected till I get a new solenoid ?

You mean the boost bypass valve? What solenoid are you referring to?

If you do mean the BBV yes some will just cap it off and bypass it completely. It won't hurt anything.

[02GTPanniversary]

Yes the solenoid below the Bybass Valve, with the sensor plugged into it, I just disconnected the vacuum line, that has the T's on it. And left that unplugged runs great, still great gas mileage, bout 22mpgs. And hauls ass.

[Fivefingerdeathpunch]

um thats a bad idea to leave the vacuum lines unplugged, your cars running SUPER lean.

22mpg is pretty bad really, seeing how I can get 30ish and 24ish mixed.

You should fix the issue for real this time.

[02GTPanniversary]

Well I just got the car about 2 weeks ago, so I haven't driven it long enough to get up that high in mpg. I have been kinda getting on it seeing as I have a 45 min ride to work, I also only run 89 octane. Alls I'm doing is unplugging the vacuum line connecting to the left side of the solenoid, it still runs acts fine, and gets just about full boost, like one block away from full.. It'll get to full takes a mintue, you think if I just replace the solenoid it'll fix the issue?

[02GTPanniversary]

I'm only leaving the one unplugged from the solenoid, nothing else