Hesitation 2,000-3,000 RPM Confused!!
08-03-2011, 08:12 PM
#1
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Hesitation 2,000-3,000 RPM Confused!! I just got a 2000 WS6 And I'm in need of some help now.. I got it and the engine light was on for a fuel system too lean because of a vacuum leak that i found and fixed.. Now the engine light is off and i have no codes in the computer..
Now i have a hesitation between 2 & 3,000 Rpm then it snaps out of it and takes off like crazy. I have a really good scanner at work and i have looked at all the live data for the O2 sensors, MAF and about anything else that i could think of that would cause this issue, Checked Fuel pressure. (its good) everything seems normal.. but its not running like it should and i know that for sure.. anyone have any suggestions? Oh and Fuel Filter is new, I have cleaned the MAF seemed like it was better for a day or so but didn't ever go away completely...
Sorry for the long post but i want all the info i have to be out there about my problem to save some time
Thanks
Jason
Now i have a hesitation between 2 & 3,000 Rpm then it snaps out of it and takes off like crazy. I have a really good scanner at work and i have looked at all the live data for the O2 sensors, MAF and about anything else that i could think of that would cause this issue, Checked Fuel pressure. (its good) everything seems normal.. but its not running like it should and i know that for sure.. anyone have any suggestions? Oh and Fuel Filter is new, I have cleaned the MAF seemed like it was better for a day or so but didn't ever go away completely...
Sorry for the long post but i want all the info i have to be out there about my problem to save some time
Thanks
Jason
08-03-2011, 08:48 PM
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Try disconnecting the battery for 10 to 15 mins completely, then hook it all back up and let your computer learn the air/fuel settings again, 10 to 15 mins should let the PCM reset itself.
08-04-2011, 06:00 AM
#4
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Thread Starter
thanks... I will let you know how it goes today after work
Ok I put the car on a scanner this afternoon and went on my lunch break.. while on my drive it quickly set a Cat efficiency code P0420.. which is new. My fuel trims were way way way out of the ordinary LTFTB1 178 LTFTB2 178 STFTB1 -28 STFTB2 -20
Im assuming it was because I didn't reset them after i fixed the massive vacuum leak..
once i reset the adaptive learns on the PCM They went LTFTB1 -8 LTFTB2 -8 STFTB1 0 STFTB2 0
but i still have the hesitation I think its the MAF to be honest
Ok I put the car on a scanner this afternoon and went on my lunch break.. while on my drive it quickly set a Cat efficiency code P0420.. which is new. My fuel trims were way way way out of the ordinary LTFTB1 178 LTFTB2 178 STFTB1 -28 STFTB2 -20
Im assuming it was because I didn't reset them after i fixed the massive vacuum leak..
once i reset the adaptive learns on the PCM They went LTFTB1 -8 LTFTB2 -8 STFTB1 0 STFTB2 0
but i still have the hesitation I think its the MAF to be honest
08-04-2011, 07:53 PM
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I'm dying to hear what you come up with, because my 2000 Trans Am is doing the same thing. Falls on it's face between 2k-3k RPMS but no check engine light. I found out my MAF looked like this,
and even after cleaning it I am still having the exact same problems. Replaced all O2 sensors and driver side CAT and same problems (cat efficiency code). I want this damn thing fixed because I can barely peel the tires out of the hole and it just feels slow unless im WOT.
and even after cleaning it I am still having the exact same problems. Replaced all O2 sensors and driver side CAT and same problems (cat efficiency code). I want this damn thing fixed because I can barely peel the tires out of the hole and it just feels slow unless im WOT.
08-04-2011, 08:24 PM
#6
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Thread Starter
My MAF looked about like that when i cleaned it out and it seemed to clear it up a little bit for a few days... but it never went away completely, but the good news is that it did change it so i do believe its the MAF sensor.. The reason for me thinking its the MAF is because that is one thing along with O2 Sensors that will really screw with your fuel trims, and other than when i had the vacuum leak i never had any CAT codes until today, and i believe they were set because i never reset the adaptive learns on the computer after i fixed that..
I'm going to put mine on a lab scope tomorrow.. Hopefully there will be some apparent fault in the wave form...
I'm going to put mine on a lab scope tomorrow.. Hopefully there will be some apparent fault in the wave form...
08-04-2011, 09:02 PM
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I'm dying to hear what you come up with, because my 2000 Trans Am is doing the same thing. Falls on it's face between 2k-3k RPMS but no check engine light. I found out my MAF looked like this,
http://i53.tinypic.com/1zvpy0j.jpg
and even after cleaning it I am still having the exact same problems. Replaced all O2 sensors and driver side CAT and same problems (cat efficiency code). I want this damn thing fixed because I can barely peel the tires out of the hole and it just feels slow unless im WOT.
http://i53.tinypic.com/1zvpy0j.jpg
and even after cleaning it I am still having the exact same problems. Replaced all O2 sensors and driver side CAT and same problems (cat efficiency code). I want this damn thing fixed because I can barely peel the tires out of the hole and it just feels slow unless im WOT.
