[Z06] VR Power Duct making car run lean
Thread Starter
Instructor
Joined: Jan 2007
Posts: 178
Likes: 2
From: Lorton VA
VR Power Duct making car run lean
I just installed the VR Power Duct (where the MAF Sensor is moved close to the throttle body) to my existing Blackwing intake. After driving for about 45 minutes (both city & highway), I get the Check Engine light. The DIC indicates that it's running lean (P01071 & P01074 Codes). Is this normal? I'm assuming the duct is now delivering more air (hence the code) or is it because the MAF is closer to the throttle body?
I read in the Forum that a lot of guys with the VaraRam CAI are getting the same codes but I just have the VaraRam Power Duct only (not the whole intake). Do I need to get this car tuned or will it adjust after a while (I also read somewhere in the Forum that the car's computer senses this change in air volume and eventually adjust after a while)?
Thanks.
I read in the Forum that a lot of guys with the VaraRam CAI are getting the same codes but I just have the VaraRam Power Duct only (not the whole intake). Do I need to get this car tuned or will it adjust after a while (I also read somewhere in the Forum that the car's computer senses this change in air volume and eventually adjust after a while)?
Thanks.
Last edited by taegee2; Apr 26, 2009 at 12:02 PM. Reason: spelling
Race Director
Joined: Sep 2005
Posts: 11,060
Likes: 291
From: Pasco WA
I have a modded car with H/C Fast, and tuned. I added the Powerduct and relocated my MAF and got codes too. I reset them a couple of times, and finally just ignored the friggin' light. It went off on it's own after a few starting cycles, and hasn't returned yet.
Drifting
Joined: Apr 2006
Posts: 1,876
Likes: 0
From: Edmond OK
I had a Vararam CAI, and when I added the power duct, got the same lean codes. I reset them and haven't had any issues.
I've been taking it a little easier, and when I install my headers in a week or so I'll be getting a tune anyway.
Good luck.
I've been taking it a little easier, and when I install my headers in a week or so I'll be getting a tune anyway.
Good luck.
Race Director
Joined: Mar 2008
Posts: 12,413
Likes: 502
From: Rio Rancho NM
I'm getting the same exact codes and I can reset the check engine light but it just comes back on. I'm afraid to get on it now since it's saying it's running lean. I also live 5,600 ft above sea level and it's even less air up here. I have had it on for a few weeks and it hasn't gone away. What do you guys suggest and do you have links to the others that where having issues?
Melting Slicks
Joined: Jul 2008
Posts: 2,000
Likes: 2
I have the same problem. Took the car up to a local vette tuner and he said that the stock air bridge really limits air flow and that with my Vararam intake in combination with the Vararam air bridge I really should get a tune to correct the lean codes. I was getting the codes multiple times each outing so I put the stock bridge back on.
Race Director
Joined: Mar 2008
Posts: 12,413
Likes: 502
From: Rio Rancho NM
Well I can say it's doing it's job then. I'm assuming the tuner will have to add some fuel in somewhere to compansate for the extra air? I figured I would wait untill i get a set of headers and then tune so I might as well put the stocker back on till then.
Instructor
Joined: Sep 2008
Posts: 239
Likes: 0
From: the woodlands tx
same year and color with 27100 miles 
, same intake and vr tunnel port, and same codes.
I've noticed they don't come on anymore with the weather now up to 80 degrees. When it was in the 60-70's, would throw the same 2 codes every start up. Have arh headers and puttin them on this week, then tune time.
, same intake and vr tunnel port, and same codes.I've noticed they don't come on anymore with the weather now up to 80 degrees. When it was in the 60-70's, would throw the same 2 codes every start up. Have arh headers and puttin them on this week, then tune time.
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Thread Starter
Instructor
Joined: Jan 2007
Posts: 178
Likes: 2
From: Lorton VA
Thanks for the inputs from all. I guess I have several options here. Just leave it alone and see if it goes away. Have it tuned (maybe even a new header...any suggestions on headers?), or as a last resort, go back to the stock air bridge and keep the same Blackwing intake (never had problems with this layout).
Melting Slicks
Joined: Aug 2008
Posts: 3,451
Likes: 27
From: Bay Area CA
You need to have it tuned. The larger airbridge is making the car run too lean and the ECM cannot compensate. Some have suggested to swap to a C6 MAF (with screen), but in my opinion, that's a band-aid fix. Get the car tuned and pick up 10-15rwhp.
Le Mans Master
Joined: Jun 2001
Posts: 7,331
Likes: 518
From: Admit Nothing, Deny Everything, Make Counter Accusations.
These leans codes are NOT being caused by additional airflow. They are being caused by inaccurate MAF readings, probably caused by turbulence. The MAF screens help distribute the air evenly across the heated wire in the MAF, which helps the MAF get a more accurate reading.
The truth of the matter is that the aftermarket airbridges and airboxes are not really flowing more air during closed loop cruising, which is when you are getting the codes.
The truth of the matter is that the aftermarket airbridges and airboxes are not really flowing more air during closed loop cruising, which is when you are getting the codes.
Melting Slicks
Joined: Sep 2005
Posts: 2,568
Likes: 264
From: Near Charlotte NC
I installed my VR power coupler in Dec and never had any trouble/codes.I've had the VR CAI for 3 years.No Codes.
Last week I got the 171 & 174 codes.I took the coupler off and cleaned the MAF.I also made sure I didn't re-oil my K&N filter very heavy with oil.
Cleaned everything,made sure all was tight and,to make sure I didn't have an air leak,I taped over the connect points on coupler & MAF.
No codes and runnin' great.
About the coupler,I'm not sure if it makes a diff,but it looks great with the VR system.
\db2
Carolina
Last week I got the 171 & 174 codes.I took the coupler off and cleaned the MAF.I also made sure I didn't re-oil my K&N filter very heavy with oil.
Cleaned everything,made sure all was tight and,to make sure I didn't have an air leak,I taped over the connect points on coupler & MAF.
No codes and runnin' great.
About the coupler,I'm not sure if it makes a diff,but it looks great with the VR system.
\db2
Carolina
Last edited by dbaker; Apr 27, 2009 at 06:16 AM.
Race Director
Joined: Mar 2008
Posts: 12,413
Likes: 502
From: Rio Rancho NM
These leans codes are NOT being caused by additional airflow. They are being caused by inaccurate MAF readings, probably caused by turbulence. The MAF screens help distribute the air evenly across the heated wire in the MAF, which helps the MAF get a more accurate reading.
The truth of the matter is that the aftermarket airbridges and airboxes are not really flowing more air during closed loop cruising, which is when you are getting the codes.
The truth of the matter is that the aftermarket airbridges and airboxes are not really flowing more air during closed loop cruising, which is when you are getting the codes.
Melting Slicks
Joined: Jul 2008
Posts: 2,000
Likes: 2
I’ve gotten the codes at different times. The times when I noticed it right away were during 3 autox runs, costing down a hill twice, during a WOT pull once, and 3 times right after a WOT pull. The many other times I just looked down and it was on. Maybe I'll throw it back on since it's warmer out and see if it does it.
All the connections were tight and everything was double checked so I don't think there were any leaks. On the other hand I did not clean my MAF before installing the Vararam air bridge only after taking it off.
All the connections were tight and everything was double checked so I don't think there were any leaks. On the other hand I did not clean my MAF before installing the Vararam air bridge only after taking it off.
Thread Starter
Instructor
Joined: Jan 2007
Posts: 178
Likes: 2
From: Lorton VA
I will probably get it tuned....question is, professional or the DIY programmer like the DiabloSport Predator? I guess both have pros and cons (the professional will probably do a more precise tune and maybe a tad more HP but I would have to go back if I want to return back to stock....the programmer probably not as much HP but I can return back to stock anytime). Any suggestions?
By the way, (going off the topic) just got accent stripes put on the front fenders (both sides) today. They are reflective red, and boy do they reflect at night. Definitely adds color and matches the red brake calipers on the Z06. These are custom made by a friend who owns a graphics shop..He put a different color on his, a subdued reflective which give it a low key look...looks like dark grey (almost black) but silver when light reflect off it (both vettes are black) and now he wants to change to red (it stands out more). Instead of the two stripes that the Vette shops sell, we added a third thin stripe...looks sharp and sporty (not that the Vette already isn't). We are doing the rear tomorrow (just seems something is missing with just the front stripes). I will try to post pics as soon as they are done. He wil have them available for sale if anyone is interested.
By the way, (going off the topic) just got accent stripes put on the front fenders (both sides) today. They are reflective red, and boy do they reflect at night. Definitely adds color and matches the red brake calipers on the Z06. These are custom made by a friend who owns a graphics shop..He put a different color on his, a subdued reflective which give it a low key look...looks like dark grey (almost black) but silver when light reflect off it (both vettes are black) and now he wants to change to red (it stands out more). Instead of the two stripes that the Vette shops sell, we added a third thin stripe...looks sharp and sporty (not that the Vette already isn't). We are doing the rear tomorrow (just seems something is missing with just the front stripes). I will try to post pics as soon as they are done. He wil have them available for sale if anyone is interested.
