Car Miss-fires above 50mph
03-27-2013, 08:55 PM
#1
Teching In
Thread Starter
iTrader: (2)
Join Date: Aug 2012
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
Car Miss-fires above 50mph I recently put a different cam in my car and 42lb injectors.
We tuned the car on the dyno, had no issues. Then when I went out to drive it, it started to act up.
I will be driving along on the highway and the car will fall on its face just staying at a steady pace. I give it throttle, it wont accelerate, just miss and pops. If I come to a stop and let it idle for a bit it will clear up and i'll be on my way.
-It does it very randomly on the highway. Some of the time it does it, sometimes it wont.
-When I go up a slight incline is when it does it the worst.
-Plugs look great
-Smells of gas very bad when it does it
-Short term fuel trims add a whole lot
-o2$ have around 3k miles on them at the most
-Wiring is checked to make sure I didn't mix up bank 1 and 2 o2$.
-Wideband reads full lean(wideband on bank 2)
-HP tuners showed it was adding a lot of fuel to bank 1 in short term fuel trims
-Long Term fuel trims are +-2%
-I can get it on if it is not doing the problem and get to redline. It wont mess up.
-Only does it at part throttle
I have already changed out to some different injectors and maf to try to cure the problem. I did get a p0101 which threw a red flag that it was a maf. So I replaced my SLP maf with a stock unit and it still did it.
My thoughts:
On the old tune that never had this issue, lean cruise was off. We turned it back on after the dyno runs. It is set at 55mph.
Short in wiring? Injectors on bank 1 loosing power? - Checked fuses, replaced with a 25 just for grins
If it wont do it under 50mph wouldn't it be the lean cruise? How would that cause it?
Thanks in advance! Any help is appreciated!
We tuned the car on the dyno, had no issues. Then when I went out to drive it, it started to act up.
I will be driving along on the highway and the car will fall on its face just staying at a steady pace. I give it throttle, it wont accelerate, just miss and pops. If I come to a stop and let it idle for a bit it will clear up and i'll be on my way.
-It does it very randomly on the highway. Some of the time it does it, sometimes it wont.
-When I go up a slight incline is when it does it the worst.
-Plugs look great
-Smells of gas very bad when it does it
-Short term fuel trims add a whole lot
-o2$ have around 3k miles on them at the most
-Wiring is checked to make sure I didn't mix up bank 1 and 2 o2$.
-Wideband reads full lean(wideband on bank 2)
-HP tuners showed it was adding a lot of fuel to bank 1 in short term fuel trims
-Long Term fuel trims are +-2%
-I can get it on if it is not doing the problem and get to redline. It wont mess up.
-Only does it at part throttle
I have already changed out to some different injectors and maf to try to cure the problem. I did get a p0101 which threw a red flag that it was a maf. So I replaced my SLP maf with a stock unit and it still did it.
My thoughts:
On the old tune that never had this issue, lean cruise was off. We turned it back on after the dyno runs. It is set at 55mph.
Short in wiring? Injectors on bank 1 loosing power? - Checked fuses, replaced with a 25 just for grins
If it wont do it under 50mph wouldn't it be the lean cruise? How would that cause it?
Thanks in advance! Any help is appreciated!
