2003 chevy malibu 3.1 liter V6 MAF sensor

You need the MAF sensor, don’t try to bypass it, and the air temp sensor does little other than to tell the computer how warm the air going into the engine is so it can make minute fuel trim changes. The MAF is the major player in determining fuel trim, so it needs to stay in the loop. If you are going to add anything to the stock engine, you may need adapters to keep the MAF sensor connected in the proper place.

Is the intake system you want to use designed for this particular application, or are you trying to make it work? A link to the component you are looking at will help determine if it’s feasible or not.

Do not bypass any of the sensors on the engine, they are all there for a reason.

The following is based on my experience, of having just installed a Weapon R Dragon intake on my 1999 Chevy Prizm.

I installed a short ram intake that was designed specifically for my car. The OE maf sensor fit perfectly into the Weapon R intake. The hose from my evap system got connected in via a hose they sent me to reach the new location. Everything looked perfect.

Anyone worried yet? Yes, the directions with the intake were kind of hard to follow, but everything logically went together. Within 2 days I had all kinds of EVAP codes on my Check Engine Light (CEL). I thought, well, I had an EVAP code for 9 years that I couldn’t resolve, until I saw under my factory air box the disconnected/broken hose. Shouldn’t this have fixed it?

A couple weeks later of following the Weapon R instructions to not really step on it, to warm up the car first, I managed to drive over 300 miles with no incident. My early morning drive to work and the codes were back (I thought maybe it was the cold air). Lots of reading on forums later, one key phrase stood out. This series of EVAP codes can be caused by the EVAP system not being grounded.

Duh!

I had pulled all these grounded EVAP systems off my original air box and had not re-grounded them to the car.

So, long story short, if Weapon R designed it for your car, I think find everything hooks in right, but be prepared for my solution. Put a bolt through your flailing EVAP system components, hook them up to a grounding wire and hook them to ground.

I look forward to giving further feedback when I drive enough to see if my solution worked. At that time, I’ll also include the P codes, I didn’t want to guess, I have a print out of them, but they aren’t right on hand. Okay, an incomplete list from my phone pic’s, I have print outs to share more of them later: P0420 P0446 P0441. The last 2 refer to the EVAP system purge flow. Hopefully, now that they’re grounded they’ll be “happy”. 🙂 The P0420, I still worry if it’ll come up due the short ram air intake getting more air in my car…anyone have experience with that? Thanks to a fancier OBD II at AutoZone, I saw the system believes my O2 sensor bank 1, or the upriver 02 sensor, is in working order, but it is noticing a problem. I have about 110k to 120k miles on that sensor though. . . or is it 90k miles? I’m at 165k miles now so it’s been a while.

[quote=”redfury” post=218]As far as the line goes, you don’t have to use the one on the new intake if the purpose is already resolved by the intake manifold. All that hose is there for is to allow the engine block to circulate air through the PCV valve and back into the intake. You are better off having the non PCV side of the system either being dumped into your air cleaner box or after the throttle body to avoid things from getting mucked up with oil residue.[/quote]

Leaving it stock, I’m not sure how he could do that. It’s going to go in before the throttle body but after the air clearer, if my experience serves. Yes, it’ll get sort of an “oil dust” look on the throttle body after a while. I recently bought throttle body cleaner and it cleaned right up easily. My throttle body looked clean before my K&N Air filter at about 80k to 90k, so maybe oil based filters do make more of a mess…but hey the K&N Air Filter got me a few miles per gallon and is cheaper in the long run. I don’t think it’s a big deal to just clean the throttle body now that I’ve done it 85k later.