March 15, 2025, 11:11:01 PM

Author Topic: LT1 runs perfect until it warms up then stumbles A LOT  (Read 9185 times)

Offline FCs Rule

._________________________
|.....Overnight.....................| ||
|........Japan Parts................||'|";,___.
|_..._...____________======||_|_|...,]
"(@)'(@)""'''''''''''''"'''"**|(@)(@)*****"(@)

hate to say it but i told you so!

Offline gadzooks

  • Supporting Member
  • Launching!
  • Posts: 1347
  • Got Torque?
  • View Gallery
    • View Profile
Re: LT1 runs perfect until it warms up then stumbles A LOT
« Reply #31 on: December 30, 2010, 02:51:28 PM »
don't get the Bosch ones, especially if you're running headers, the heating elements are not very good, I've personally had good luck so far with NTK's
1987 Base/Light Weight with '95 Firebird LT1/T5

Offline Nyt_Muves

Re: LT1 runs perfect until it warms up then stumbles A LOT
« Reply #32 on: December 31, 2010, 01:27:24 AM »
DING DING DING
We have a WINNER
It was the O2 sensors. 
Unplugged them and drove around.  It is a whole different car now. 
Even unplugged, I didn't get a code until I had been driving around without them for over 20 Min. 

Thank you all SO much for all of the help and ideas.  Funny thing is that it was more than one problem.  It was the O2 sensors, but also the intake issue.  Crazy. 
Built by Mazda, Shaken by PONTIAC
LT and T56 going in!! Ford 5.0L and AOD for sale.  lol :D

Offline whitehot

Re: LT1 runs perfect until it warms up then stumbles A LOT
« Reply #33 on: December 31, 2010, 01:43:56 AM »
I've had no problem with the Bosch ones. When I bought my car it was running super rich and was acting the same way you described. When I finally hooked the Tunercat up it was throwing codes for both of them. New ones and it was like a different car.
-Scotty
-88 TII -- forged 355 LT1/T56

Offline skinnies

Re: LT1 runs perfect until it warms up then stumbles A LOT
« Reply #34 on: January 04, 2011, 03:44:21 AM »
DING DING DING
We have a WINNER
It was the O2 sensors. 
Unplugged them and drove around.  It is a whole different car now. 
Even unplugged, I didn't get a code until I had been driving around without them for over 20 Min. 

Thank you all SO much for all of the help and ideas.  Funny thing is that it was more than one problem.  It was the O2 sensors, but also the intake issue.  Crazy.
No problem, I've messed with A LOT of lt1's over the years and seen this come up a lot.
1st gen rx7 -  76mm junkyard 5.3, 8.65 at 167.9, first stock shortblock ls in the 8's!
1985 Ford LTD - 9.7 at 144, junkyard 5.3/76mm on 235 drag radials, 10.25 at 142 on street tires(no drag radials)