[Z06] Surging
Thread Starter
Burning Brakes
Joined: Apr 2007
Posts: 1,030
Likes: 1
From: Douglasville Ga
Surging
Ok....i was driving down the interstate this morning (~80 mph) and had the cruise on in 6th gear. The engine was at 2000-2100 rpm. When I started going downhill the car would start to surge a little, and then it would stop when I went uphill. Was this just because she has very little power in 6th gear and was coasting downhill??
Advice!!!!
Nick
Advice!!!!
Nick
Thread Starter
Burning Brakes
Joined: Apr 2007
Posts: 1,030
Likes: 1
From: Douglasville Ga
the only mod that I have right now is a blackwing. I cut a hole in the shroud under it to let more air flow through the filter. and it probably does need a tune, but I am going to wait until I put the headers and x-pipe on this winter until i do that.
Race Director
Joined: Aug 2000
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From: Central Florida
A bit of surge is characteristic of most CAI installations.
One small step you can do is checking the air-path connections for tightness.
Tuning the PCM will not necessarily solve this minor annoyance.
Ranger
Melting Slicks
Joined: Sep 2003
Posts: 2,062
Likes: 117
Ok....i was driving down the interstate this morning (~80 mph) and had the cruise on in 6th gear. The engine was at 2000-2100 rpm. When I started going downhill the car would start to surge a little, and then it would stop when I went uphill. Was this just because she has very little power in 6th gear and was coasting downhill??
Advice!!!!
Nick
Advice!!!!
Nick
I still have it today and the results in my application are superior to some others intakes (CAI) I have tested and monitored.
Then the power the engine is doing in my sig is with the Blackwing PLUS the ICEBOX, daily driven, no surging bucking.
The only way to make your Air Filter efficient and avoid this typicall surging due to Hot Air aspirated by the engine from the underhood in decel and Ambient air aspirated by the engine on throttle through the hole in the shroud which is sending the PCM contradictory information is to mount a cover over your filter...
As simple as this, your PCM will learn his Fuel Trims (short and long term) from the Ambient Air (the PCM is build around this function) and no need for a retune...
Christian
Race Director
Joined: Jan 2006
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From: Not on either liberal coast.
I had a BLACKWING, "ice box" cover, after market air bridge, smooth bellows and open shroud. I didn't get any surging, but I got intermittent codes that drove me nuts. I'm sure it was related to the extra air and my altitude at 5,200 ft. I chose not to get a $500 dyno tune and make the 300 mile round trip to the nearest tuner. I removed mine and returned to the Z16 intake with an after market filter and slightly enlarged the air inlet...sounds the same as the BLACKWING, runs the same and I get no annoying codes.
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Melting Slicks
Joined: Sep 2003
Posts: 2,062
Likes: 117
Hi hotwheels57,
Did you search to know about or did you simply interpret your codes???
The PCM is so nicely done that those codes reported to your dashboard where the key to the solution of your problems...first work on that item!!! isn't it nice to know why a problem is there and where it is???
But it had nothing to do with the Blackwing or any other CAI...may be something wrong in the install!!! (subtil leak?)
The codes will tell it.
Christian
Race Director
Joined: Jan 2006
Posts: 10,554
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From: Not on either liberal coast.
I pulled the codes in the DIC and asked here about them...they were intermittent lean banks on both sides. I cleared them several times and they'd reappear after 50-75 miles of varied driving.
The first time I got a code, I found that the smooth/rigid after market throttle body to over sized after market air bridge bellows had a pucker beneath the throttle body that I missed during installation. I only found it with a complete examination of every clamping point using a small mirror. The pucker was maybe 1/4" long and impossible to see w/o the mirror. The oem worm screw clamp was tight, but clamping only a portion of the bellows. I now use stainless t-bolt clamps on my intake where ever possible.
The first time I got a code, I found that the smooth/rigid after market throttle body to over sized after market air bridge bellows had a pucker beneath the throttle body that I missed during installation. I only found it with a complete examination of every clamping point using a small mirror. The pucker was maybe 1/4" long and impossible to see w/o the mirror. The oem worm screw clamp was tight, but clamping only a portion of the bellows. I now use stainless t-bolt clamps on my intake where ever possible.
Melting Slicks
Joined: Sep 2003
Posts: 2,062
Likes: 117
I pulled the codes in the DIC and asked here about them...they were intermittent lean banks on both sides. I cleared them several times and they'd reappear after 50-75 miles of varied driving.
The first time I got a code, I found that the smooth/rigid after market throttle body to over sized after market air bridge bellows had a pucker beneath the throttle body that I missed during installation. I only found it with a complete examination of every clamping point using a small mirror. The pucker was maybe 1/4" long and impossible to see w/o the mirror. The oem worm screw clamp was tight, but clamping only a portion of the bellows. I now use stainless t-bolt clamps on my intake where ever possible.
The first time I got a code, I found that the smooth/rigid after market throttle body to over sized after market air bridge bellows had a pucker beneath the throttle body that I missed during installation. I only found it with a complete examination of every clamping point using a small mirror. The pucker was maybe 1/4" long and impossible to see w/o the mirror. The oem worm screw clamp was tight, but clamping only a portion of the bellows. I now use stainless t-bolt clamps on my intake where ever possible.
Both lean bank are significative of a leak in the intake system...can be solve by a close examination as you did.
BUT nothing related to the Air Filter (Blackwing or else), the flow of any aftermarket air filter will be so easely compensated by the PCM, your Long Term Fuel Trim are working for you on that, and margin is huge!!!
A bad mounted system breathing hot air from the inside hood and ambient air from the outside or any leak will create problems to your car...the PCM will detect the problem and will find a way to go on some "safe mode" (going lean when the MAF is receiving hot less dense air in decel in the case of this thread---then bucking) or will send you infos (the famous codes...)
Christian
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From: Lenoir City TN
St. Jude Donor '08-'09-'10-'11
Had the same problem on my 02 with the Vararam installed (was on the car when I bought it) so I installed the stock air box back in and the problem went away, I was lucky since the seller had kept the stock air box.
Race Director
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From: Not on either liberal coast.
I'm at 5,200 ft altitude with lean air as it is. It was explained to me that the PCM could not adjust enough for the increase in air intake from the cold air intake BLACKWING system as it was probably close to being outside it factory parameters as it was when stock...(maximum 24% +/_ comes to mind?). That's why I considered a professional tune.
Thinking I was still possibly taking in some warm engine compartment air, I completely resealed the "ice box" cover with fresh 1/4" foam seal. There was absolutely no manner for warm engine air to enter the covered BLACKWING...all of it was coming from the open shroud.
Anyway, I don't want to take away from the original posters question...maybe my experience will give him some insight into his issues. Thanks!
Thinking I was still possibly taking in some warm engine compartment air, I completely resealed the "ice box" cover with fresh 1/4" foam seal. There was absolutely no manner for warm engine air to enter the covered BLACKWING...all of it was coming from the open shroud.
Anyway, I don't want to take away from the original posters question...maybe my experience will give him some insight into his issues. Thanks!
Last edited by hotwheels57; Aug 3, 2007 at 07:25 PM.
Thread Starter
Burning Brakes
Joined: Apr 2007
Posts: 1,030
Likes: 1
From: Douglasville Ga
Thanks for all the input guys...I seperated the air bridge from the MAF sensor and found "TWO" puckers on the bottom. I did that after church tonight so I haven't had a chance to fix it and try it out, but I will let you know what the fix does. Again, thanx for all the advice.
Nick
Nick
Thread Starter
Burning Brakes
Joined: Apr 2007
Posts: 1,030
Likes: 1
From: Douglasville Ga
Yeah.....I bought the car with the blackwing and never thought to look for that sort of thing.
....Ok. I fixed the puckers in the bottom of the intake. They had been there for so long that the puckers were almost a permenant ripples. Anyway, i had a little scare to start off with. I had unplugged the TPS and forgot to plug it back in to start with and the DIC was giving me a "
Reduced Power" readings. I plugged it back in and went for a spin. Surging has reduced, but is still there a little and the check engine light is on. I haven't read the code yet, but could this just be that the engine is still changing the air/fuel ration??
....Ok. I fixed the puckers in the bottom of the intake. They had been there for so long that the puckers were almost a permenant ripples. Anyway, i had a little scare to start off with. I had unplugged the TPS and forgot to plug it back in to start with and the DIC was giving me a "
Reduced Power" readings. I plugged it back in and went for a spin. Surging has reduced, but is still there a little and the check engine light is on. I haven't read the code yet, but could this just be that the engine is still changing the air/fuel ration??
Last edited by Bigstik; Aug 5, 2007 at 11:10 AM.
Race Director
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From: Not on either liberal coast.
Your MAF sensor wires could be dirty from intake of the unmetered/dirty air. Pick up a can of MAF cleaner (or electrical contact cleaner), not carburetor or choke cleaner. You want a chemical that leaves no chemical residue.
You can also use a Q-tip and alcohol, but you have to be very careful of the wires.
The computer is probably trying to relearn which might take a few miles of driving to achieve.
You can also use a Q-tip and alcohol, but you have to be very careful of the wires.
The computer is probably trying to relearn which might take a few miles of driving to achieve.
Thread Starter
Burning Brakes
Joined: Apr 2007
Posts: 1,030
Likes: 1
From: Douglasville Ga
I took the car to work today (40 miles round trip). The check engine light went off, but the car is still surging, not as bad but its there. Could this be from the 102 degree air that it is sucking in from outside?
102
It really only does it when I'm going downhill.
102
It really only does it when I'm going downhill.