Finished Supercharger and Valve cover Gaskets - now getting the P0171 System Lean

[jimmyrecluse]

Bank One. The live data on the 02 looks good, I sprayed a can of brake cleaner looking for vacuum leaks. MAF is clean. No codes before the installation.

Seems to be a common issue with all sorts of possible solutions.

I'd like to keep the stock fuel system

I've searched, but do we have any definitive steps to take? I dont want to throw parts at it until it's solved.

 

[spartacus]

P0171 lean likely a vacuum leak.Make sure all the hoses are connected and some have reported a port on the back of the supercharger needing to be capped. There is a little plug goes on the left of the manifold of the charger, right next to the throttle body that needs to be capped. Some even say it's a learning curve and will go away.

 

[LittleCaesar]

What exactly are the short and long term fuel trim numbers when warmed up? How old are the O2 sensors?

 

[jimmyrecluse]

P0171 lean likely a vacuum leak.Make sure all the hoses are connected and some have reported a port on the back of the supercharger needing to be capped. There is a little plug goes on the left of the manifold of the charger, right next to the throttle body that needs to be capped. Some even say it's a learning curve and will go away.

Thanks for the reply, the kit came with 2 And both are placed in the correct spot. I sprayed brake cleaner all over the hoses and where the supercharger bolts to the manifold, no change in idle, but a vacuum leak is what i suspected. I do have this high pitch whistle under load and past 1/3 throttle that gets progressively higher pitched as the throttle goes closer to the floor. I can't replicate it with the car sitting still while under the hood, but it sounds like a vacuum leak causing the whistling. I think it's coming from the air hose where that hard plastic nozzle comes off, I didn't include it in my original post because I didn't want to sway anyone to thinking it was that

 

[jimmyrecluse]

What exactly are the short and long term fuel trim numbers when warmed up? How old are the O2 sensors?

I've owned the vehicle for about 5 years and put on 45K miles during that time period I had never change the MAF nor 02 sensors, I don't know when or if they had been replaced before that

There were no issues before the supercharger

Trim levels are, 3.3 and 3.9% at idle. The levels range between negative 12% and 10% on up to 19% while revving the engine

 

[Lamer]

not sure if these will help, but this was my vacuum line map I made for my supercharger install

 

[jimmyrecluse]

I appreciate this. I followed the diagrams in the back of the installation booklet and everything else went back where it was, I will cross reference with your diagrams.

Did you have any issues using the stock fuel system?

 

[gamefreakgc]

The P0171 isn't because the engine doesn't have enough fuel. You've got a vacuum leak. +19% when revving the engine (not even under boost yet) means there's air getting in.

Double check your vacuum hose routing, it's year specific so consult the manual. If that doesn't show any issues tighten down the two nuts and three bolts that hold down the supercharger a bit more. I had a leak there once because I left one of those bolts too loose.

To reiterate and put your mind at ease, this is not a fuel delivery issue. It's a vacuum leak caused by a misplaced hose or gasket on wrong or too loose.

 

[mtbtim]

I appreciate this. I followed the diagrams in the back of the installation booklet and everything else went back where it was, I will cross reference with your diagrams.

Did you have any issues using the stock fuel system?

I don't know if you know about our video for this install but maybe it will help you notice something you could have missed.

<iframe width="560" height="315" src="https://www.youtube.com/embed/7RmHXvEQwXs" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

 

[jimmyrecluse]

I don't know if you know about our video for this install but maybe it will help you notice something you could have missed.

<iframe width="560" height="315" src="https://www.youtube.com/embed/7RmHXvEQwXs" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

Yes I checked it out and it was a big help but got murky in areas because of the used kit. It's on and it runs but now I've got this code.. I suspect a stubborn vacuum leak that existed before but it's so minor I'm having trouble finding it

 

[jimmyrecluse]

The P0171 isn't because the engine doesn't have enough fuel. You've got a vacuum leak. +19% when revving the engine (not even under boost yet) means there's air getting in.

Double check your vacuum hose routing, it's year specific so consult the manual. If that doesn't show any issues tighten down the two nuts and three bolts that hold down the supercharger a bit more. I had a leak there once because I left one of those bolts too loose.

To reiterate and put your mind at ease, this is not a fuel delivery issue. It's a vacuum leak caused by a misplaced hose or gasket on wrong or too loose.

I suspect a vacuum leak and have tightened down the 3 bolts and two nuts holding the supercharger on but also realize I have talking to other people that are just as sure as yourself that it could be sensor's or further down-the-line a fuel issue. Vacuum leak is number one on my list because I'm certain I have something somewhere even before the install
But I'm having major trouble finding it. Like I said before the super charger, when I gave it gas, throttle, 1/3 of the way to the floor under load while on a street I could hear a loud whistle and it sounds like an air whistle. Doesn't do it parked in the driveway with me under the hood

 

[jimmyrecluse]

I believe I've resolved it

Part of the issue was that I was given a step by Magnuson, who have been great and responsive through this, that applies to a different year vehicle

While looking around and going over the hoses that I connected, I saw something at the back of the supercharger where it bolts on to the throttle body. Lo and behold there is an inlet that was not connected to anything

In the diagrams in the back of the manual it shows that it connects to the vacuum throttle opener

Under the guidance of the manufacture I had capped the vacuum throttle opener, which is why I didn't have a corresponding end to end place to connect a hose at the back of the supercharger

Such as stupid oversight, but so far. No code and runs better

 

[eddielasvegas]

Good news.

Please post your impression of the SC after a few weeks of driving.

I really want to do this to my T4R3G but seeing these types of threads always gives me pause as I value reliability and dependability above all else.


Eddie

I believe I've resolved it

Part of the issue was that I was given a step by Magnuson, who have been great and responsive through this, that applies to a different year vehicle

While looking around and going over the hoses that I connected, I saw something at the back of the supercharger where it bolts on to the throttle body. Lo and behold there is an inlet that was not connected to anything

In the diagrams in the back of the manual it shows that it connects to the vacuum throttle opener

Under the guidance of the manufacture I had capped the vacuum throttle opener, which is why I didn't have a corresponding end to end place to connect a hose at the back of the supercharger

Such as stupid oversight, but so far. No code and runs better

 

[jimmyrecluse]

[MENTION=289564]eddielasvegas[/MENTION]

So far it feels like a V8. Obviously well made unit. Boosts at the rights times, can drive conservatively and it feels close to stock.

For the cost, it comes down to your use. I take mine into the hills, large freeway inclines and steep paved climbs as well as off road. Will def help on freeway inclines and going up the 330 to big bear.

As far as reliability, my thinking was this was at one point TRD branded and offered as a dealer option. But I dont expect it to prolong engine and trans life, if you know what I mean

 

[Lamer]

[MENTION=289564]eddielasvegas[/MENTION]

So far it feels like a V8. Obviously well made unit. Boosts at the rights times, can drive conservatively and it feels close to stock.

For the cost, it comes down to your use. I take mine into the hills, large freeway inclines and steep paved climbs as well as off road. Will def help on freeway inclines and going up the 330 to big bear.

As far as reliability, my thinking was this was at one point TRD branded and offered as a dealer option. But I dont expect it to prolong engine and trans life, if you know what I mean

I would look into adding an external trans cooler inline with your radiator. and a trans fluid temp sensor if you don't have one already. Tim makes a great install video

 

[eddielasvegas]

Thanks jimmyrecluse.

You're pulling me back in to the land of SC's. Hahaha.

The hunt for a used 2nd gen is on.

Eddie

[MENTION=289564]eddielasvegas[/MENTION]

So far it feels like a V8. Obviously well made unit. Boosts at the rights times, can drive conservatively and it feels close to stock.

For the cost, it comes down to your use. I take mine into the hills, large freeway inclines and steep paved climbs as well as off road. Will def help on freeway inclines and going up the 330 to big bear.

As far as reliability, my thinking was this was at one point TRD branded and offered as a dealer option. But I dont expect it to prolong engine and trans life, if you know what I mean

 

[jimmyrecluse]

I would look into adding an external trans cooler inline with your radiator. and a trans fluid temp sensor if you don't have one already. Tim makes a great install video

I've installed a larger, all aluminum, radiator

Trans temp sounds good, is on the list.