Removing my Vararam VRB2
Thread Starter
Melting Slicks
Joined: Jul 2010
Posts: 2,503
Likes: 33
From: McGrady NC
St. Jude Donor '15-'16
Removing my Vararam VRB2
I'm tired of fighting the constant Check Engine lights for lean conditions as a result of installing a Vararam. I'm using the stock air bridge with the MAF in the stock location and the Check Engine light pops on every time I crank the car when it's hot with DIC codes P0171 and P0174, both lean codes. I've tried the VR Power Bridge, moved the MAF close to the throttle body, etc. with no real improvement so, unless I'm missing something that will make it work for me, off it comes.
I don't want to spend more money on a tune at the moment just to make it work so I'm seriously removing it (watch the Parts for Sale section soon). I just spent a pile on fixing a dropped valve after a valve spring failure to I'm tapped out at the moment.
Can I just pull it out from the top after disassembling it down to the basic sections or do I have to run back through the installation steps backwards, which is a real pain? I intend to replace the stock air cleaner assembly for now.
Does anyone have any experience with this?
I don't want to spend more money on a tune at the moment just to make it work so I'm seriously removing it (watch the Parts for Sale section soon). I just spent a pile on fixing a dropped valve after a valve spring failure to I'm tapped out at the moment.
Can I just pull it out from the top after disassembling it down to the basic sections or do I have to run back through the installation steps backwards, which is a real pain? I intend to replace the stock air cleaner assembly for now.
Does anyone have any experience with this?
Last edited by CaseyJones; Mar 29, 2016 at 09:06 AM.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Have you tried cleaning the MAF, checking for air leaks between the MAF and TB?
How many miles on the car. Are the O2 Sensors failing. A sluggish O2 sensor can cause this issue.
Find someone with a scanner with LIVE SENSOR Monitoring capabilities or some one with EFI Live or HP Tuners and check those functions.
Your O2 sensor/s should be cycling from (APPROX) 100milliamps to (approx). 900 milliamps.
How many miles on the car. Are the O2 Sensors failing. A sluggish O2 sensor can cause this issue.
Find someone with a scanner with LIVE SENSOR Monitoring capabilities or some one with EFI Live or HP Tuners and check those functions.
Your O2 sensor/s should be cycling from (APPROX) 100milliamps to (approx). 900 milliamps.
Le Mans Master
Joined: Dec 2005
Posts: 8,475
Likes: 332
From: Port Arthur, Texas 77642
Halltech is supporting vendor. I copied / pasted the below from their website. The product is $49.99.
Halltech Honeycomb 1/8" Cell Laminar Flow Straightener is a direct 1 minute plug and play high flow straightener designed for the C5 Corvette style Delphi MAF meter; It also fits the 2005-2007 C6 base car LS2 (not the LS7). This unit will eliminate lean codes on the 2001-2004 C5 Z06 in all aftermarket intake applications. It can also replace the 1/16" honeycell on the LS1-LS2 MAF, which is very restrictive. (See Larger Pics section) These aluminum honeycomb screens are very fragile and cannot be returned.
Interestingly, this eliminates lean codes on many intakes made by Vararam, and other turbulent bottom breathers. The two MAFs shown in the picture are for illustration of stock vs. our honeycomb flow straightener. You are purchasing only the honeycomb and using your stock MAF meter.
>Halltech Honeycomb Laminar Flow Straightener
>Fits ALL Delphi 85 MAF sensors
>Completely eliminates lean codes common with aftermarket intakes when used on the C5 Z06
>Eliminates surging caused by turbulence at the MAF on the 01-04 C5 Z06
>Aluminum honeycomb
>Easy to install in 1 minute
http://www.halltechsystems.com/Hallt...r-p/hc.125.htm
Halltech Honeycomb 1/8" Cell Laminar Flow Straightener is a direct 1 minute plug and play high flow straightener designed for the C5 Corvette style Delphi MAF meter; It also fits the 2005-2007 C6 base car LS2 (not the LS7). This unit will eliminate lean codes on the 2001-2004 C5 Z06 in all aftermarket intake applications. It can also replace the 1/16" honeycell on the LS1-LS2 MAF, which is very restrictive. (See Larger Pics section) These aluminum honeycomb screens are very fragile and cannot be returned.
Interestingly, this eliminates lean codes on many intakes made by Vararam, and other turbulent bottom breathers. The two MAFs shown in the picture are for illustration of stock vs. our honeycomb flow straightener. You are purchasing only the honeycomb and using your stock MAF meter.
>Halltech Honeycomb Laminar Flow Straightener
>Fits ALL Delphi 85 MAF sensors
>Completely eliminates lean codes common with aftermarket intakes when used on the C5 Z06
>Eliminates surging caused by turbulence at the MAF on the 01-04 C5 Z06
>Aluminum honeycomb
>Easy to install in 1 minute
http://www.halltechsystems.com/Hallt...r-p/hc.125.htm
Thread Starter
Melting Slicks
Joined: Jul 2010
Posts: 2,503
Likes: 33
From: McGrady NC
St. Jude Donor '15-'16
No leaks for sure and I will clean the MAF. The car has 74K miles on it. I'm getting lean conditions on both banks so would that point to both primary O2 sensors going bad?
Thread Starter
Melting Slicks
Joined: Jul 2010
Posts: 2,503
Likes: 33
From: McGrady NC
St. Jude Donor '15-'16
Halltech is supporting vendor. I copied / pasted the below from their website. The product is $49.99.
Halltech Honeycomb 1/8" Cell Laminar Flow Straightener is a direct 1 minute plug and play high flow straightener designed for the C5 Corvette style Delphi MAF meter; It also fits the 2005-2007 C6 base car LS2 (not the LS7). This unit will eliminate lean codes on the 2001-2004 C5 Z06 in all aftermarket intake applications. It can also replace the 1/16" honeycell on the LS1-LS2 MAF, which is very restrictive. (See Larger Pics section) These aluminum honeycomb screens are very fragile and cannot be returned.
Interestingly, this eliminates lean codes on many intakes made by Vararam, and other turbulent bottom breathers. The two MAFs shown in the picture are for illustration of stock vs. our honeycomb flow straightener. You are purchasing only the honeycomb and using your stock MAF meter.
>Halltech Honeycomb Laminar Flow Straightener
>Fits ALL Delphi 85 MAF sensors
>Completely eliminates lean codes common with aftermarket intakes when used on the C5 Z06
>Eliminates surging caused by turbulence at the MAF on the 01-04 C5 Z06
>Aluminum honeycomb
>Easy to install in 1 minute
http://www.halltechsystems.com/Hallt...r-p/hc.125.htm
Halltech Honeycomb 1/8" Cell Laminar Flow Straightener is a direct 1 minute plug and play high flow straightener designed for the C5 Corvette style Delphi MAF meter; It also fits the 2005-2007 C6 base car LS2 (not the LS7). This unit will eliminate lean codes on the 2001-2004 C5 Z06 in all aftermarket intake applications. It can also replace the 1/16" honeycell on the LS1-LS2 MAF, which is very restrictive. (See Larger Pics section) These aluminum honeycomb screens are very fragile and cannot be returned.
Interestingly, this eliminates lean codes on many intakes made by Vararam, and other turbulent bottom breathers. The two MAFs shown in the picture are for illustration of stock vs. our honeycomb flow straightener. You are purchasing only the honeycomb and using your stock MAF meter.
>Halltech Honeycomb Laminar Flow Straightener
>Fits ALL Delphi 85 MAF sensors
>Completely eliminates lean codes common with aftermarket intakes when used on the C5 Z06
>Eliminates surging caused by turbulence at the MAF on the 01-04 C5 Z06
>Aluminum honeycomb
>Easy to install in 1 minute
http://www.halltechsystems.com/Hallt...r-p/hc.125.htm
Melting Slicks
Joined: Feb 2001
Posts: 2,804
Likes: 358
From: Northville, MI
At 74K you also need to replace the O2's. When our cars were built the O2's were based on regular gas, with almost all areas using 10% ethanol, GM redesigned the O2's to withstand the higher alcohol content. When I replaced mine at 33K I could see the difference on my scan logs in how fast they were reacting and the extra swing in ma's.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
I could say YES! They are bad but,,, UNTIL, you scan them and actually see them react (cycle) it would just be a guess. With 74k on the clock,, there no spring chickens!
I can say that if they are weak, installing new ones will make the engine run much better and give you much better fuel economy.
I added VARARAL and Headers to my 02 Zo6 and I didn't get one DTC or light! Even without a tune.
I can say that if they are weak, installing new ones will make the engine run much better and give you much better fuel economy.
I added VARARAL and Headers to my 02 Zo6 and I didn't get one DTC or light! Even without a tune.
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Thread Starter
Melting Slicks
Joined: Jul 2010
Posts: 2,503
Likes: 33
From: McGrady NC
St. Jude Donor '15-'16
I could say YES! They are bad but,,, UNTIL, you scan them and actually see them react (cycle) it would just be a guess. With 74k on the clock,, there no spring chickens!
I can say that if they are weak, installing new ones will make the engine run much better and give you much better fuel economy.
I added VARARAL and Headers to my 02 Zo6 and I didn't get one DTC or light! Even without a tune.
I can say that if they are weak, installing new ones will make the engine run much better and give you much better fuel economy.
I added VARARAL and Headers to my 02 Zo6 and I didn't get one DTC or light! Even without a tune.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
The ONLY sensors that do anything for the fueling of the engine are the primary sensors.
The AFTER THE CAT sensors only tell the PCM that the CATs are working fine.
SO,, Unless the after the CAT sensors are throwing DTCs, I wouldn't worry about them. I have the A.I.R. System REMOVED and those sensors tuned out!
The standard OEM/Auto parts store BOSH sensors work fine.
BC
The AFTER THE CAT sensors only tell the PCM that the CATs are working fine.
SO,, Unless the after the CAT sensors are throwing DTCs, I wouldn't worry about them. I have the A.I.R. System REMOVED and those sensors tuned out!
The standard OEM/Auto parts store BOSH sensors work fine.
BC
Instructor
Joined: Dec 2012
Posts: 214
Likes: 26
I used to always get the p0171 and p0174 with my vararam, bought a haltech honeycomb installed it, havent seen those codes since, its been 2 years. When you do install it use some gloves the edges are really sharp, also dont forget to clean your maf, and disconnect the battery or reset pcm so it can relearn.
Thread Starter
Melting Slicks
Joined: Jul 2010
Posts: 2,503
Likes: 33
From: McGrady NC
St. Jude Donor '15-'16
I ordered the Halltech screen earlier today. If that fixes my problem then the VRB2 stays. I've just had so many problems with my car over the past few months (really since last July) that I just want life to get a little easier.
Burning Brakes
Joined: Aug 2010
Posts: 1,051
Likes: 54
From: Raleigh NC
Your working it out though. By summer youll be good. Have you tried relocating the maf to a different spot on the intake?
Thread Starter
Melting Slicks
Joined: Jul 2010
Posts: 2,503
Likes: 33
From: McGrady NC
St. Jude Donor '15-'16
Le Mans Master
Joined: Dec 2005
Posts: 8,475
Likes: 332
From: Port Arthur, Texas 77642
If you visit HPT forum there are many there using the honeycomb screens. Available from another source with different thickness and honeycomb cell sizes for different applications, MAF tube sizes, etc.. They indeed do work as advertised and Jim Hall has it nailed for the C5Z 85mm MAF.
Glad to see you're going to give it a try before removing your Vararam, I think that would be a step backwards.
Glad to see you're going to give it a try before removing your Vararam, I think that would be a step backwards.
Thread Starter
Melting Slicks
Joined: Jul 2010
Posts: 2,503
Likes: 33
From: McGrady NC
St. Jude Donor '15-'16
I received my Halltech screen Saturday and installed it. I also removed the battery cable to reset the PCM. After a long drive yesterday, I only had the CEL pop up for the same Bank 1 (P0171) and 2 (P0174) lean conditions once and that was after an extended stop for church service. I immediately cleared it from the DIC and it didn't came back all day even after several shutdowns and restarts.
The car runs better but still seems to have a little hesitancy at light throttle cruising. I have new upstream O2 sensors on my workbench and will install them as soon as I get time from daily life stuff. I'm happy that the car runs better but there is still room for improvement.
The car runs better but still seems to have a little hesitancy at light throttle cruising. I have new upstream O2 sensors on my workbench and will install them as soon as I get time from daily life stuff. I'm happy that the car runs better but there is still room for improvement.
Burning Brakes
Joined: Aug 2010
Posts: 1,051
Likes: 54
From: Raleigh NC
The new O2's will probably make all the difference. Thinking of getting new ones for mine also after reading this thread! Glad you got it worked out. We've had some horror stories lately lol