supercharger emission testing

[Raque Thomas]

I would think that a missing O2 sensor and/or a missing MAF sensor would have your check engine lit up - no, I know that those things missing would throw a code, unless the wiring has been chaged (ie, you can add resistance and fool the system into thinking the MAF is present and working). I'm with Cyrk - I doubt the installer would have removed these items; to do so would open them up to pretty large fines. Did you try another testing location?

[nater]

Intake Gaskets! Intake Gaskets! Intake Gaskets!

They are likely leaking, letting air in that is unmetered. The O2 sensor code is probably a side affect.

It could also be the fuel pressure regulator isn't high enough, but this engine is notorious for Intake Gaskets leaking. If you reused the old ones for the S/C install, there is your likely culprit.

Nate

[Hotsauce]

I did the installation.

I agree, intake or more likely EGR leak.

John C.

[Triathlete]

When my non-SC'd VX was reading lean in bank 1 I had a clogged fuel rail. Tapped on it to loosen it up and ran some injector cleaner through the system and it has been fine ever since.

[Medman]

Thanks for getting back to me. Tell me more about these intake gaskets. Now that I think about it, about three months ago I needed to have a gasket replaced by my local Isuzu dealer. What happened was that my truck would putter and nearly stall unless I nearly pushed the gas pedal to the floor, and the surge of gas would get the truck moving again. If I came to a stop, the car would stall. I had it towed to a dealer, they replaced some sort of gasket . . . . problem solved. Lately, the same symptoms have been happening. The engine would putter and nearly stall unless I give it a fair amount of gas, then the truck would start moving normally. The dealer said something about the fuel line being clogged and the gasket having something to do with it, and by flooring the pedal I was forcing gas to clear any obstruction and the truck would go.

Do you think this could have anything to do with this "EGR gasket"? Could a blown EGR gasket cause all these emission error codes? If I get the gasket replaced like last time, do you think the truck would pass emissions? Tell me what you all think. Thanks in advance for any suggestions.

[SGT.BATGUANO]

Did you bring it in with the check engine light lit? Is this an active or a stored code. I'm pretty sure all your sensors are in place, but may not be working properly. You may have an intake or egr leak . Search those topics for more info

[Corey872]

What were your numbers on the emissions test? If your O2 sensors and MAF are really gone (or non functional) the computer is probably in open loop mode (not getting any feedback from the sensors) and dumping in a little extra fuel as a failsafe. In this instance, your HC and possibly CO would probably be high, NOX would probably be low.

If you have an intake gasket issue, this would allow unmetered air into the engine and result in a lean condition. NOX would probably be high with low HC and CO. Likewise with the ERG, if it is failed or plugged it will show up as high NOX, too.

HTH - Post the actual #'s and limits if you can.

Good Luck
Corey