post Procharger install issue - car pegged rich - undriveable

[nick97ns]

I just recently installed a Procharger d1sc stage two kit on my 16' GT. Before install, everything was running perfect (i was running a FBO setup). My prior tune was done with Lund so I decided to use them again for this setup. Before the first startup after the install, I obviously loaded up my new base map for the car. But upon first start up the car wouldn't idle properly, the car would die out unless I gave it some throttle and when I did give it throttle, the RPMS would surge all over the place. The car had minimal throttle response at a standstill.

Lund has sent me multiple different tunes after I send them logs, and no matter what the car keeps behaving the same way. They keep saying the car is pegged rich and something is off fueling wise. Finally, they found the tune from the guy that I bought the ProCharger system off of and they sent me basically his tune with some slight modifications to fit my car since i do have an 18 mani.

Upon startup, the car immediately died, but on the second startup I gave it some throttle and it began to idle well and everything was seemingly running well at this point. I then took it for a drive around the block and the car immediately started hesitating and had 0 throttle response once I tried driving it. I thought we had made some progress but it seems as if we're back at square one. Car is just pegged rich. AFR reading super high.

I've smoked the car out with a smoker and there are no vacuum leaks, I've triple checked the MAF to make sure the wires/pins are all intact and that it's not facing the wrong way (theres only one way to screw it in), Ive taken the injectors out and had lund verify that they are indeed DW95 injectors & I've gone over the entire install and everything we added multiple times and the ProCharger system itself is all working well.

Lund is now suggesting I try replacing the front O2 (wideband) sensors, even though I haven't touched those since my longtube install over a year ago. Ill give that a go but I honestly don't have much hope for that. Does anyone have any suggestions on what might be going on? Or has anyone had a similar experience and found a fix?

If anyone asks, the current mods are:
Stage 2 Procharger sytem (D1SC unit)
DW95 injectors
VMP bap
TSP longtubes, w/ xpipe and axleback
Ported 18' manifold IMRC locked out

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[aleccesarenriquez]

I had this issue when I was using a charge pipe that was the wrong size for the maf housing. Pegged rich, couldn't idle until I created an induced vacuum leak, and even then it was still undriveable. Ended up fabbing a charge pipe with the right diameter and it worked like a champ.

Could try throwing the stock air box on to see if it'll idle nicely. If it does, that'll be a good clue.

Edit: forgot this was a procharger. Not sure if your car will run without the procharger connected since it's belt fed. I remember my Paxton couldn't

 

[ahl395]

The O2s weren't touched from install so I think that's an unlikely cause. The MAF was though however. Even if the pins are right the MAF could be bad. I would replace it.

Did you install a BAP? Try disconnecting it from the system if so.

 

[80FoxCoupe]

Maf intercooler or throttle body pipe?

 

[nick97ns]

Maf intercooler or throttle body pipe?

maf in tube!

 

[nick97ns]

The O2s weren't touched from install so I think that's an unlikely cause. The MAF was though however. Even if the pins are right the MAF could be bad. I would replace it.

Did you install a BAP? Try disconnecting it from the system if so.

Thats also what i was thinking as well, I have a MAF waiting for me at my local ford. But my tuner is saying that the MAF is reading fine, and that i should start with the oxygen sensors first. I do have a vmp BAP so ill give that a go and see if it makes any difference.

 

[nick97ns]

I had this issue when I was using a charge pipe that was the wrong size for the maf housing. Pegged rich, couldn't idle until I created an induced vacuum leak, and even then it was still undriveable. Ended up fabbing a charge pipe with the right diameter and it worked like a champ.

Could try throwing the stock air box on to see if it'll idle nicely. If it does, that'll be a good clue.

Edit: forgot this was a procharger. Not sure if your car will run without the procharger connected since it's belt fed. I remember my Paxton couldn't

The charge pipe im using is the one supplied from procharger specifically made for these cars, and the MAF fits in it perfectly. So i dont really think thats the problem here, but its a great point and could be a possible cause. And yeah i dont think i could run it with the stock airbox like that, plus i dont even have it anymore lol.

 

[80FoxCoupe]

maf in tube!

Is it possible that maf is scaled for use in intercooler?

 

[nick97ns]

Is it possible that maf is scaled for use in intercooler?

I really don't think so, the tuner knows the MAF is in the tube. The data was so skewed the first few times that he even made me verify that it's in the tube by sending a picture of it. Not to mention the tune name says MAF in tube on it. Good suggestion though, i wish it was that simple :(

 

[Torinate]

They’re positive they have the correct injector data for the tune? If they have 72s in by accident and you’ve got 95s on the car, would act the same as you’re describing.

Duh... reread your post... already checked... sorry


Stabbing in the dark...

 

[nick97ns]

They’re positive they have the correct injector data for the tune? If they have 72s in by accident and you’ve got 95s on the car, would act the same as you’re describing.

Duh... reread your post... already checked... sorry


Stabbing in the dark...

if only it was that simple :/

 

[SheepDog]

The charge pipe im using is the one supplied from procharger specifically made for these cars, and the MAF fits in it perfectly. So i dont really think thats the problem here, but its a great point and could be a possible cause. And yeah i dont think i could run it with the stock airbox like that, plus i dont even have it anymore lol.

Is it possible that the MAF pipe is installed backwards, so the MAF sensor is facing the wrong way? When you say AFR's are high, what do you mean exactly? high numbers indicate a lean condition, not rich. What are your STFT's?

 

[nick97ns]

Is it possible that the MAF pipe is installed backwards, so the MAF sensor is facing the wrong way? When you say AFR's are high, what do you mean exactly? high numbers indicate a lean condition, not rich. What are your STFT's?

There's only one way to install the MAF into the tube due to the orientation of the screw holes, and yes it is facing the correct way. That was the first thing I double-checked.

To be completely transparent, I'm not well versed on what's what data-wise. But here's the screenshot my tuner sent me. The STFT's are in there as well. This is all a learning process for me.

 

[SheepDog]

There's only one way to install the MAF into the tube due to the orientation of the screw holes, and yes it is facing the correct way. That was the first thing I double-checked.

To be completely transparent, I'm not well versed on what's what data-wise. But here's the screenshot my tuner sent me. The STFT's are in there as well. This is all a learning process for me.

Take a short log at idle, once the engine is warm. no throttle input. .63 AFR does indicate a rich condition, but the fact that your log shows LTFT and STFT are a perfect 1.0 Lambda is unlikely. Do you have any codes stored? Even if the check engine light isn't on, there could be history codes saved. If the PCM isn't receiving a good signal from the primary O2 sensors, it will add fuel in an effort to protect the engine from running lean. There are very few things mechanically that can cause a rich condition, but generally it is caused by bad O2 sensors or a bad/dirty MAF. Does the engine misfire?

Also, I see you have long tube headers. Be certain that the O2 sensors are plugged in completely and that whatever wiring extender you are using hasn't failed.

 

[nick97ns]

Take a short log at idle, once the engine is warm. no throttle input. .63 AFR does indicate a rich condition, but the fact that your log shows LTFT and STFT are a perfect 1.0 Lambda is unlikely. Do you have any codes stored? Even if the check engine light isn't on, there could be history codes saved. If the PCM isn't receiving a good signal from the primary O2 sensors, it will add fuel in an effort to protect the engine from running lean. There are very few things mechanically that can cause a rich condition, but generally it is caused by bad O2 sensors or a bad/dirty MAF. Does the engine misfire?

Also, I see you have long tube headers. Be certain that the O2 sensors are plugged in completely and that whatever wiring extender you are using hasn't failed.

Thanks for all the amazing insight. This weekend I'm going to check out the O2 sensors/harness and potentially replace them as well. I'll check for the stored codes as well and get back to you on that. And no the car isn't misfiring.

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