Rough idle and sputtering at about 1500 rpms
06-02-2016, 06:40 PM
#1
Teching In
Thread Starter
Join Date: Jun 2016
Location: Los Angeles, CA
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
Rough idle and sputtering at about 1500 rpms Im having a problem with my 1998 z28. When in idle its a lil rough. And when i start driving and is at 1500 rpms it starts hesitating/ sputtering until about 2000 rpms but when WOT it runs perfectly fine. Only rough when low rpms. Ive cleaned the MAFs, changed spark plugs and sparkplug wires already.. Dont know if this will help but ran a scanner on it like 2 months back and P0442 code came up. Thanks in advance
06-08-2016, 12:23 AM
#4
Emissions will vent when intake is under vac, so around idle since that is when it will pull in. Sounds like something is leaking or something stuck open, so you are getting dirty and/or unmetered air causing a run issue. As you get up in RPM vac goes down so it draws less from there and at WOT it will draw almost none from it, so it would run normal.
12-27-2017, 02:52 PM
#5
Im having a problem with my 1998 z28. When in idle its a lil rough. And when i start driving and is at 1500 rpms it starts hesitating/ sputtering until about 2000 rpms but when WOT it runs perfectly fine. Only rough when low rpms. Ive cleaned the MAFs, changed spark plugs and sparkplug wires already.. Dont know if this will help but ran a scanner on it like 2 months back and P0442 code came up. Thanks in advance
Anyone thought about the throttle positioning sensor? I know it’s old but people still come around looking for answers. I’m having this problem right now and am frankly shocked not to see the tsp as a solution. Hope this helps someone
09-25-2022, 02:13 PM
#6
Registered User
Join Date: Sep 2022
Posts: 1
Likes: 0
Received 0 Likes
on
0 Posts
1500 RPM and 2000 RPM rough I am starting to think ita the AFM in the automatics for Gen 5, I have a 2010 SS, only 40,000 miles and the engine and exhaust run smooth in both feel and sound. When I am maintaining speed at 1500 rpms or 2000 rpms the exhaust sounds rough and there is someone of a rough feel to the engine. If I am accelerating it is smooth and sounds solid. Sometimes while braking the downshift will bounce a bit. But leaning towards the AFM and poaaibly the torque converter S I have heard other had that issue diagnosed.
