supercharger emission testing

[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

[Hotsauce]

The new inspection(at least for AWD) is not with the tail snifter, they just plug into the OBD2 port and look for codes. Any code and you fail, no matter what tailpipe is doing.

John C.

[Tone]

They have passed in CA with aftermarket exhausts many times and for intial certification. Might want to clear codes before taking it in...or fix the problem - it is not the supercharger or the exhaust. Intial CARB testing and certification was done with stock airbox in place.

[Hotsauce]

That particular series of codes usually sets only during high vacuum decelleration, you probably can clear the code just before testing and test clear. Then you will be able to solve the reason without being under the gun.

You can borrow my scantool.

John C.

[nater]

Personally, I would start with new intake gaskets, check to make sure the fuel pressure regulator modification was done properly, and try again. (Yes, the S/C has to come off again for this). This seems to be the more likely culprit than sensors, injectors, etc.

Anyone else have better insight? (Agree/ Disagree?)

Nate