Results 1 to 20 of 44
-
07-08-2011, 04:28 AM #1
idle is fine with A/C on but jumpy when its off?
Hi guys. i recently did the LS6 valley cover upgrade. Its been fine but I did noticed that when the car's a/c is off the idles tends to get jumpy. the car kinda jerks lightly but it doesn't shut off. Im just wondering why will the idle be almost perfect with the a/c on. The RPM stays steady at 800 with the a/c on and about 700 with a/c off.
Prior to the valley cover upgrade i had idle issues. I found out that the valley cover gasket was bad when i replaced the valley cover.
I have a question about the 3 way valve that sits by the PCM area. I know one vacuum line comes from the back of the intake to it. Then it splits in two: one to the inside of the car and one goes to the front of the vehicle thru the passenger side of the engine bay. Where does this line going towards the front connects to? I even capped that line and there is no changes in the idle but i wonder where does it goes to. Thanks.
-
07-08-2011, 04:51 AM #2
- Join Date
- Nov 1999
- Location
- over here...
- Age
- 45
- Posts
- 25,709
[]D [] []V[] []D- 1999 trans am
my car usually raisees the rpm by 100 or so when i turn the AC on... seems normal...
-
07-08-2011, 05:12 AM #3
-
07-08-2011, 05:47 AM #4
-
07-08-2011, 01:45 PM #5
- Join Date
- Jan 2009
- Location
- North Jersey
- Posts
- 11,496
Phantom Black Metallic- 2004 GTO M6
Could be the A/C putting a parasitic drag on the engine while the compressor is on, causing the idle to drop so the erradic idle isn't really noticed. Without the A/C running, is the idle lopey?
-
07-11-2011, 03:42 PM #6
with the a/c the idle is almost perfect I don't notice anything wrong. with the a/c off the idle feels like it spikes. it almost feels when a spark plug is bad or arcing. I changed the wired like 6 months ago. The plugs were changed around 10k ago with ngk
tr55's. Today the car spiked hard for like a second. most of the time it stays kinda spiky but is not a steady pattern. it could be fine for like 5 second and then spikes. I guess because i have poly mounts i feel it more.
I might go ahead and replace the plugs this weekend and check the wires as well. I had this problem since I own the car. It used to happen all the time even with the a/c on. Since i changed the valley cover it doesn't do it with the a/c on anymore or at least i don't notice it. No SES light.
-
07-11-2011, 04:16 PM #7
- Join Date
- Jan 2009
- Location
- North Jersey
- Posts
- 11,496
Phantom Black Metallic- 2004 GTO M6
It could be the current draw from the fans. Are the plugs TR55's or TR55 IX?
-
07-11-2011, 04:21 PM #8
-
07-11-2011, 04:38 PM #9
-
07-11-2011, 09:25 PM #10
what mods do you have and is the car tuned? Idle airflow will change when you turn the a/c on so that might be helping your idle issue. You say you had this issue before the valley cover? Same exact issue?
-
07-20-2011, 04:33 AM #11
well i noticed this morning that when I was leaving work(cold engine) I put it in drive and the rpms drop to 500. I put it in neutral and it got alittle better but I can tell something was going on. I put in reverse and same thing. I kinda of heard some clunking noise in the engine area when I tried to move but it stopped. i put it in neutral again and the rpms went back up to 800. I park and waited for a bit and everything was normal again. Drove all the way home with no issues.
Not sure if it is related with my initial post here. The car never died. im going to replace the plugs today. Im thinking maybe i shoud replace my IACV but it cost around $110.
-
07-21-2011, 04:21 PM #12
yes i had this issue before but it got better with the valley cover. Today I changed the spark plugs. They looked okay but I will post pics of them. I checked my plug wires and 4 of them showed open, now thats kinda of rare as i will think the car will missfire. Im not sure if the cables are snaping when i pull them out. I start the car and the idle is alot better.
Everytime I change the plugs and replace wires it seems to get better and then with time it goes back to the same issue. Im not sure if the cables are degrading. I will keep an eye on the idle and post updates.1998 TA 130k A4, LS6 intake, TunedByFrost, Airlid, AIR and EGR delete, Borla exhaust, front Eibach lowering springs, LS6 valley cover, UMI TQ arm, UMI LCA's, UMI panhard bar, Poly engine mounts, BMR relocation brackets, Blistein HD shocks and struts, Oil catch can, Autotrix window fix.
Now I have an 2001 F150 5.4L
-
07-21-2011, 05:04 PM #13
- Join Date
- Jan 2009
- Location
- North Jersey
- Posts
- 11,496
Phantom Black Metallic- 2004 GTO M6
Do you clean your engine and engine compartment? If you do, what do you use to clean it with?
-
07-21-2011, 05:08 PM #14
-
07-21-2011, 05:22 PM #15
- Join Date
- Jan 2009
- Location
- North Jersey
- Posts
- 11,496
Phantom Black Metallic- 2004 GTO M6
OK. I only ask as I was wondering if the stuff you used possibly ate through your plug wires.
-
07-21-2011, 07:18 PM #16
I'm nominating you second in line this week for the "my knock sensors are bad" thread These motors hate water.....nothing but bad can come of putting water on them.
How close are your plug wires to your headers? If they're close enough the headers will dry out and crack plug wires.....and it doesn't take as long as you might think. My buddy has a 98 vette and his #7 wire is right on that primary. Even with kevlar sleeves he has to replace that wire every couple years depending on how much he drives the car.
-
07-21-2011, 07:23 PM #17
-
07-21-2011, 07:48 PM #18
- Join Date
- Jan 2009
- Location
- North Jersey
- Posts
- 11,496
Phantom Black Metallic- 2004 GTO M6
You didn't overtighten those sensors...did ya? Just asking as if you under/overtighten them, they will create a "false knock".
-
07-21-2011, 07:52 PM #19
-
07-21-2011, 10:32 PM #20
did you upgrade to the 99+ sensors and harness or just replace the 98's? The 98 sensors are fairly retarded really....way more sensitive than the 99+.
Thread Information
Users Browsing this Thread
There are currently 1 users browsing this thread. (0 members and 1 guests)
Similar Threads
-
idle issues... idle high. unplugged tps runs good?
By okiels1 in forum Firebird / WS6Replies: 2Last Post: 12-31-2016, 03:36 AM -
How To Fix Idle Problems - Idle Time
By Ed Blown Vert in forum Firebird / WS6Replies: 0Last Post: 04-05-2012, 07:50 PM -
Help: intermittant rough idle, off idle hesitation
By Matto4785 in forum General HelpReplies: 1Last Post: 09-21-2009, 05:12 AM -
Brandon, i think it looks FINE.
By NE98LS1 in forum Almost Anything GoesReplies: 33Last Post: 07-20-2007, 08:38 AM -
fine for exhaust
By ttocs in forum Almost Anything GoesReplies: 17Last Post: 06-26-2006, 11:00 AM
Bookmarks