weird idle
03-20-2008, 02:34 AM
#1
Member
Thread Starter
weird idle
I have a 2001 4.6.
In December 07 i put on a true dual 2.5" setup with no mufflers, only the 4 cats. The rest of the motor is completely stock. Since then, sometimes when the engine is cold, or even some other times, when the motor is at idle, it will not idle at a steady number of rpms. It kind of revs up and down from about 700 to about 900 rpms. (Or maybe it is 600 to 800). It kind of sounds like it is running out of gas. But it runs great at under any other rpms.
Any ways... I was wandering what might cause this. I am almost wandering if an intake wouldn't fix it. I kind of think that the motor is letting out to much air compared to what it is able to suck in.
In December 07 i put on a true dual 2.5" setup with no mufflers, only the 4 cats. The rest of the motor is completely stock. Since then, sometimes when the engine is cold, or even some other times, when the motor is at idle, it will not idle at a steady number of rpms. It kind of revs up and down from about 700 to about 900 rpms. (Or maybe it is 600 to 800). It kind of sounds like it is running out of gas. But it runs great at under any other rpms.
Any ways... I was wandering what might cause this. I am almost wandering if an intake wouldn't fix it. I kind of think that the motor is letting out to much air compared to what it is able to suck in.
Last edited by 2001stu; 04-07-2008 at 12:41 AM.
04-04-2008, 09:43 PM
#3
hummmmm
Join Date: Jan 2008
Location: Texas
Posts: 393
Likes: 0
Received 0 Likes
on
0 Posts
I have a 2001 4.6.
In December 07 i put on a true dual 2.5" setup with no mufflers, only the 4 cats. The rest of the motor is completely stock. Since then, sometimes when the engine is cold, or even some other times, when the motor is at idle, it will not idle at a steady number of rpms. It kind of revs up and down from about 700 to about 900 rpms. (Or maybe it is 1600 to 1800). It kind of sounds like it is running out of gas. But it runs great at under any other rpms.
Any ways... I was wandering what might cause this. I am almost wandering if an intake wouldn't fix it. I kind of think that the motor is letting out to much air compared to what it is able to suck in.
In December 07 i put on a true dual 2.5" setup with no mufflers, only the 4 cats. The rest of the motor is completely stock. Since then, sometimes when the engine is cold, or even some other times, when the motor is at idle, it will not idle at a steady number of rpms. It kind of revs up and down from about 700 to about 900 rpms. (Or maybe it is 1600 to 1800). It kind of sounds like it is running out of gas. But it runs great at under any other rpms.
Any ways... I was wandering what might cause this. I am almost wandering if an intake wouldn't fix it. I kind of think that the motor is letting out to much air compared to what it is able to suck in.
04-09-2008, 11:51 PM
#5
Junior Member
Join Date: Apr 2008
Posts: 11
Likes: 0
Received 0 Likes
on
0 Posts
I have a 2001 4.6.
In December 07 i put on a true dual 2.5" setup with no mufflers, only the 4 cats. The rest of the motor is completely stock. Since then, sometimes when the engine auto body part is cold, or even some other times, when the motor is at idle, it will not idle at a steady number of rpms. It kind of revs up and down from about 700 to about 900 rpms. (Or maybe it is 600 to 800). It kind of sounds like it is running out of gas. But it runs great at under any other rpms.
Any ways... I was wandering what might cause this. I am almost wandering if an intake wouldn't fix it. I kind of think that the motor is letting out to much air compared to what it is able to suck in.
In December 07 i put on a true dual 2.5" setup with no mufflers, only the 4 cats. The rest of the motor is completely stock. Since then, sometimes when the engine auto body part is cold, or even some other times, when the motor is at idle, it will not idle at a steady number of rpms. It kind of revs up and down from about 700 to about 900 rpms. (Or maybe it is 600 to 800). It kind of sounds like it is running out of gas. But it runs great at under any other rpms.
Any ways... I was wandering what might cause this. I am almost wandering if an intake wouldn't fix it. I kind of think that the motor is letting out to much air compared to what it is able to suck in.
04-10-2008, 11:40 PM
#6
Member
Thread Starter
i changed plugs boots and 2 coilpacks at 95,000 mi. and i change the oil every 3000. it has done it over the past 2 or 3 oil changes
04-11-2008, 02:01 AM
#7
I Voted For Bill and Opus
You need to get a code reading to see what is going on. Wondering idle can be vacuum leaks causing lean surge, one of your engine sensors is bad. Did you replace the O2 sensors when you changed out the exhaust system etc. Don't start throwing parts at it see if the ODS can tell you anything first.
