GenVibe - Community for Pontiac Vibe Enthusiasts

So recently I have put in a SRI in my 2006 base vibe. I have it attached correctly and all and it has been mostly what I had expected it to be. Since installing it though it seems my car is taking a little longer to shift into the next gear upon acceleration. It doesn't jump or jerk into gear or anything just taking a little longer to switch, should I be worried about this? I continue to have my check engine light come on and have checked the code myself which i believe was to be p171 or something. But the code was a "system too lean, too much oxygen in the exhaust". Its confusing because there aren't any leaks. When I had gotten the SRI the maf sensor didn't fit into the intake tube so I had the widen the hole ever so slightly. The MAF sensor fits into the tube very well and I highly doubt that it has a leak around it. Just really confused on why I keep getting the system too lean code. Any help or advice would be appreciated!!

When you say "shifting takes longer" do you mean there is a lag going from one gear to the next , or do you mean "it revs higher before the up shift occurs"?

Normally when the P0171 gets triggered it is because it sucks in air after the MAF sensor and before the intake valve. That's what we call a vacuum leak. Make double sure that you have all vacuum hoses properly attached to the intake. Make sure the PCV system is working properly and has no vacuum leak either. It even could be possible the oil filler cap leaks air into the intake system via the PCV. I doubt that is the case though.

With modifying the intake you could have another issue: the airflow is different and it may not hit the MAF sensor straight on, therefore the sensor gets not cooled enough which the PCM interprets as low air flow. The result is less fuel injected and that leads to excess O2 at the HO2 sensor, hence the message: lean condition!

I would have to see the set up to better guess what's happening.

vibrologist wrote:When you say "shifting takes longer" do you mean there is a lag going from one gear to the next , or do you mean "it revs higher before the up shift occurs"?

Normally when the P0171 gets triggered it is because it sucks in air after the MAF sensor and before the intake valve. That's what we call a vacuum leak. Make double sure that you have all vacuum hoses properly attached to the intake. Make sure the PCV system is working properly and has no vacuum leak either. It even could be possible the oil filler cap leaks air into the intake system via the PCV. I doubt that is the case though.

With modifying the intake you could have another issue: the airflow is different and it may not hit the MAF sensor straight on, therefore the sensor gets not cooled enough which the PCM interprets as low air flow. The result is less fuel injected and that leads to excess O2 at the HO2 sensor, hence the message: lean condition!

I would have to see the set up to better guess what's happening.

Sorry for the confusion, it revs higher before the up shift occurs. The intake was originally for a Matrix but with little modification I was able to fit it to my vibe. The breather hose that was going from the engine was suppose to be replaced by a tube in the SRI kit. The tube that came with the kit was too small but I was able to shorten the original and feed some of the newer tube into the older breather hose. It is a very tight fit so it is hard to believe that is the cause of the problem. I checked the hoses and tubes today to make sure they were snug. The breather hose was tightly attached at both ends and the rubber sleeve that holds the intake pipe onto the throttle body is tightened down to both the intake and the TB. Im gonna keep looking at it to try to find the leak if there is one.

It also seems that when I accelerate it is hesitating a little instead of taking off right away.

Definitely, it is running to lean. The belated shifting could be caused by the same fault. The torque may be lower as it should and therefore the PCM waits for the up shift.

Use a piece of garden hose to listen for hissing sounds. Or use a flammable spray (carb cleaner) and spray that around tube connections and other suspect areas. Listen for a change in idle. If it does change the leak is near the sprayed area.

When you put the SRI in, did you reset the PCM? You can do that by disconnecting the battery negative cable, then stepping on the brake for a few seconds. The closed brake light circuit will drain any remaining voltage from the computer's capacitors and that resets it. It has to start over with the learning. If you have not done that do it now. Expect some roughness but it should get better over time as the computer learns the tricks.

Here is another thought, and it is only a thought because I cannot see your specific set up: Maybe the air is a bit turbulent right there where the MAF is located. See if there is an air flow straightener available for that set up. I learned about that issue in the Mazda forum.

I hate to be this guy... But it sounds like something is definitely wrong with your intake and your engine is suffering in performance. I know you don't want to hear it but maybe the stock intake is a better option. Aftermarket intakes often hurt performance more than they help. Oily K&Ns or high flow dry filters let more dirt pass by them dirtying the mass air flow sensor which hinders the computers ability to keep the engine running at peak performance.

Also keep in mind that all the throttle body is is an air restricor. So at 0-99% throttle, the engine is being 'throttled' or restricted. Therefore the only time you want more air flow is at 100% throttle and let's be honest, how often are you at 100% throttle?

Thanks for the input guys. I'm gonna disconnect the battery for the reset and check for leaks.

If the inner diameter of the SRI is bigger than stock in the MAF area it will throw the reading off regardless.
I suggest you first put the stock intake back on and see if it runs right.
If you still want to mod I suggest you re-route the inlet of the stock filter box to a cold air zone,
like behind the bumper near the lower grill.
Colder, denser air produces more power and torque across the rpm band
Works well for me.

A lean code could be causing the ECM to delay shifting without other driveability issues.

TraumaForYou wrote:The breather hose that was going from the engine was suppose to be replaced by a tube in the SRI kit. The tube that came with the kit was too small but I was able to shorten the original and feed some of the newer tube into the older breather hose. It is a very tight fit so it is hard to believe that is the cause of the problem.

Get a hose that's the same inner diameter as the original breather and cut it long enough to reach the breather inlet of the intake without kinking.

If you really don't believe it could be leaking, get some carb cleaner and spray it all over where the hoses are connected together while the engine runs and where the intake hooks to the throttle body, as well as any other possible openings downstream of the MAF. It won't throw the cod unless there is a leak; it's a stupid ECM, but if it's throwing a code, there is a problem. It's probably the SRI since it didn't have issues before, and it would have to be a leak. Otherwise, it could be the MAF, O2, or an exhaust leak on the exhaust manifold or something, but it's most likely the SRI and I recommend you test that first.

lannvouivre wrote:A lean code could be causing the ECM to delay shifting without other driveability issues.

TraumaForYou wrote:The breather hose that was going from the engine was suppose to be replaced by a tube in the SRI kit. The tube that came with the kit was too small but I was able to shorten the original and feed some of the newer tube into the older breather hose. It is a very tight fit so it is hard to believe that is the cause of the problem.

Get a hose that's the same inner diameter as the original breather and cut it long enough to reach the breather inlet of the intake without kinking.

If you really don't believe it could be leaking, get some carb cleaner and spray it all over where the hoses are connected together while the engine runs and where the intake hooks to the throttle body, as well as any other possible openings downstream of the MAF. It won't throw the cod unless there is a leak; it's a stupid ECM, but if it's throwing a code, there is a problem. It's probably the SRI since it didn't have issues before, and it would have to be a leak. Otherwise, it could be the MAF, O2, or an exhaust leak on the exhaust manifold or something, but it's most likely the SRI and I recommend you test that first.

Yeah the SRI was the problem. It was most likely the crap filter that came with it. Until i sand out where the MAF sensor sits and get a better quality filter I reinstalled the factory intake.

TraumaForYou wrote:Yeah the SRI was the problem. It was most likely the crap filter that came with it. Until i sand out where the MAF sensor sits and get a better quality filter I reinstalled the factory intake.

The filter won't make it run lean because the MAF sensor can see the air flowing in. Your problem has to be something on the intake pipe between the MAF sensor and the throttle body. It may be the wraps or the worm clamps letting unmetered air get sucked in.

lannvouivre wrote:

TraumaForYou wrote:Yeah the SRI was the problem. It was most likely the crap filter that came with it. Until i sand out where the MAF sensor sits and get a better quality filter I reinstalled the factory intake.

The filter won't make it run lean because the MAF sensor can see the air flowing in. Your problem has to be something on the intake pipe between the MAF sensor and the throttle body. It may be the wraps or the worm clamps letting unmetered air get sucked in.

Yeah that's why I'm gonna sand out the port for the sensor. Its hard to believe that its the brackets, they are the same youd be getting at AutoZone.

Whelp, I sanded out the piece that the MAF sensor fits and it now fits how it should have. I have made sure that everything it tightened down nicely but I'm still getting that damn code.

TraumaForYou wrote:Whelp, I sanded out the piece that the MAF sensor fits and it now fits how it should have. I have made sure that everything it tightened down nicely but I'm still getting that damn code.

Spray carb cleaner on the joints while the engine is running.

Cool, I'll give it a try! Thanks