Results 1 to 12 of 12
Thread: Possible closed loop issues
-
08-02-2010, 12:56 PM #1
Possible closed loop issues
I finally got my exhaust sealed up and fixed and I am going for a tune on wednesday and I have something I want to see If I can iron out beforehand.
The exhaust pressure coming out of the pass side exhaust it noticeably weaker than the driver side (I am running true duals and no mufflers so there is no blockage). I originally thought I might be down a cylinder or actually random firing on a cylinder, as I had issues with 1 coil after putting the headers on basically firing when it wanted to.
I thought I got that fixed and I pulled the wire and put in a plug and it seemed to be firing fine comparable to another coil. Weird thing is that there is no code being thrown for a misfire. also the car doesnt feel like it has the power it should.
Now today I noticed that at cold startup both sides were equal as far as pressure. But as it warmed up, and I am assuming hitting closed loop, the pass side is noticeably weaker.
Is there anything i can look into before my tune so we dont hit a wall?
I pulled the front plug on pass side (the 1 i had coil trouble with a while back,I have since changed the plugs and they only have 100 miles on them) and it was darker than the other one I pulled. So it would seem that its not firing properly for some reason.
Again weird part being that its only when the car warms up does this happen.
Any suggestions on places to start troubleshooting before I waste time for the tune?
Thanks in advance.94 m6 Formula - Sold
2000 NHRA Formula - Always For Sale
-
08-02-2010, 12:59 PM #2
-
08-02-2010, 01:08 PM #3
-
08-03-2010, 07:30 AM #4
2018 Tahoe - Silver - OEM
2008 Z06 - Velocity Yellow - BBE exhuast - Airaid CAI **sold**
2002 Z06 - Electron Blue Metallic - D1 - E85 - 701 rwhp 687 rwtq **sold**
2002 Z28: M6 NBM - cam and boltons - 396rwhp 357 rwtq **sold**
-
08-03-2010, 07:52 AM #5
-
08-03-2010, 08:56 AM #6
-
08-03-2010, 09:44 AM #7
Well as i said at cold start it is the same. after it warms up its definitly noticeable...kind of hard to explain the difference in feel... if i had to guesss, the pass side feels the same 1 in away from the pipe compared to about 8 inches on the driver side away from the pipe.
The more I think about it the more it seems like its probably not an issue. I hope the tune will either fix this or at least tell me why. I wouldnt be as concerned if it didnt feel the same at cold but different when warm.
-
08-03-2010, 10:11 AM #8
-
08-03-2010, 10:23 AM #9
-
08-03-2010, 10:43 AM #10
pretty darn close. where the pass side would normally be shorter, its actually crossed over after the axle, behind the back bumper, and run out the driver side exit in the bumper.
Im assuming the person who did the duals did so in order to keep the pipes closer to the same length instead of having the driver side being longer.
-
08-03-2010, 10:54 AM #11
- Join Date
- Jul 2009
- Location
- North of the Motorcity
- Posts
- 2,612
Custom Swirly Black- 2001 WS6 M6
The passenger side has an extra turn it or 2 in it? sounds like a couple of 90 degree turns (2 45's to get over the axel)
This will obviously slow down the flow compared the driverside, I'm not sure it would slow it down as much as you a feeling, but the actual pressure might be in the range of "normal opertation." I'm not sure how much difference in pressure there is in "normal operation." And since I'm no tuning expert either, I think it's possible with a good tune the flows should be balanced out. It's hard to say, as most people I know with true dual exhaust have a X or H pipe. Your tuner might be able to answer those questions as well before you actually get the tune done.
From my understanding you ideally want the same flow (backpressure) with your exhuast. It may be affecting your overall performace having them mismatched. But, all my expereince with exhaust true duals has been with and x or y pipe.
-
08-03-2010, 11:41 AM #12
Yeah I hear ya....it really is boggling, and concerns me, as at a cold start or open loop both sides seem equal in pressure. then after warming up, my guess going to closed loop, the pass side drops off quite a bit as compared to driver side.
And yes at the rear there are a couple extra 45 turns for pass side but with it just running through open pipe it shouldnt cut down the pressure that much. also wouldnt make sense that it matches the driver side at cold idle.
I am really hoping the tune will help or at least reassure me that it is no big deal.
My concern though was that if it was happening when going to closed loop is that it then uses different inputs from the car to adjust vs open loop. Might be an o2 sensor i guess, but i would think a code would be thrown for that.
Thread Information
Users Browsing this Thread
There are currently 1 users browsing this thread. (0 members and 1 guests)
Similar Threads
-
Open/closed loop
By c5z28 in forum Computer & TuningReplies: 6Last Post: 08-02-2010, 02:27 PM -
Help: i can't get the car into closed loop
By blackonblackws6 in forum General HelpReplies: 3Last Post: 01-12-2009, 11:45 AM -
Closed from Feb 20-25
By Sam Strano in forum Suspension and HandlingReplies: 5Last Post: 02-21-2008, 04:15 AM -
What is used for closed and open loop?
By glock22_40 in forum LT1Replies: 4Last Post: 06-29-2006, 06:28 AM
Bookmarks