Turbo +Boost Issues

[nicholas tiratsuyan]

So basically we recently got the car tuned and we had an issue with the car not holding boost. The car would rev up and only boost up to 2 psi. We have the carbon canister hooked up to the car and only when we unplug the MAF and clog the vacuum line (EVAP line) that goes to the carbon canister does it make its normal amount of boost. We've tried unplugging the MAF and keeping the carbon canister plugged in, we've tried clogging the carbon canister and keeping the MAF plugged in and we've tried plugging the MAF in and the vacuum line into the carbon canister but we still only get 2 psi. The only way we can hold boost is if we clog the vacuum line and unplug the MAF. Any ideas?

 

[ctuinstra]

I'm not the expert here but I have a few questions. During the tune, did they look at the MAF output and see anything unusual? Unplugging it uses defaults or goes into a different mode. Could it possibly be turned around and not installed facing the right direction?

 

[nicholas tiratsuyan]

The guy who did the tune calibrated the MAF so it read accuratly and it did read normaly. We checked that it was installed in the right direction.

 

[Briann1177]

Certain engine codes will disable boost. If that happens you'll basically be running off wastegate spring pressure which means it won't go any higher than about 5 psi.

EDIT. I didn't fully read your last two sentences.

 

[Desert Sasqwatch]

I'm not the expert here but I have a few questions. During the tune, did they look at the MAF output and see anything unusual? Unplugging it uses defaults or goes into a different mode. Could it possibly be turned around and not installed facing the right direction?

Or wires swapped? Is the waste gate being activated when the car is in boost?

 

[nicholas tiratsuyan]

Or wires swapped? Is the waste gate being activated when the car is in boost?

Yes. We hear the waste gate open up very shortly after the boost starts to build

 

[nicholas tiratsuyan]

Certain engine codes will disable boost. If that happens you'll basically be running off wastegate spring pressure which means it won't go any higher than about 5 psi.

EDIT. I didn't fully read your last two sentences.

Lonnie told us the same thing. The weird thing is that it only goes up to 2 rather than 5

 

[BaltimoreHokie]

I assume you do not have the old tune...or another computer. But, thats one route to try to see if it holds boost and it's not tied to the tune.

 

[nicholas tiratsuyan]

I assume you do not have the old tune...or another computer. But, thats one route to try to see if it holds boost and it's not tied to the tune.

It did it before and after the tune

 

[Desert Sasqwatch]

The boost reference supplied to the wastegate coming from the diverter valve on the intake manifold hooked up correctly?

 

[nicholas tiratsuyan]

I am pretty sure we never touched them this is how they came when we bought it.

 

[Briann1177]

The boost reference supplied to the wastegate coming from the diverter valve on the intake manifold hooked up correctly?

That is for the compressor bypass valve.

 

[nicholas tiratsuyan]

Would it have something to do with the computer?

 

[Briann1177]

If it held boost before the tune and now it doesn't, that tells me something is funky with the tune work.

I'd check for codes and if all else is clean, send it back to the tuner to put the stock tune back on. Then I'd find another tuner.

 

[nicholas tiratsuyan]

If it held boost before the tune and now it doesn't, that tells me something is funky with the tune work.

I'd check for codes and if all else is clean, send it back to the tuner to put the stock tune back on. Then I'd find another tuner.

The weird thing is that it did it before the tune as well

 

[Amack1970]

My car started doing the same thing today after filling it with gas. I haven't changed anything? No engine codes. If I start the car I'll have boost for a minute or two. Then it goes away. Shut it off and start it again the boost comes back? Not sure what's going on? Ideas

 

[nicholas tiratsuyan]

My car started doing the same thing today after filling it with gas. I haven't changed anything? No engine codes. If I start the car I'll have boost for a minute or two. Then it goes away. Shut it off and start it again the boost comes back? Not sure what's going on? Ideas

If you'd like you can give us a call and we can compare notes. We found a way around it by disconnecting the MAF sensor and plugging the evap line.

Phone Number: 9146715554