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Check Engine Light Coming On After Shifting Mistakes

886 Views 6 Replies 4 Participants Last post by  crjackson
There have been three times that my CEL has come on after I've made a shifting mistake that has made the car buckle.

The first time it happened it said the upstream O2 sensor on the driver's side was bad, and I replaced the sensor. All good. But it did come on when I had almost stalled the car out due to not having enough gas when I shifted from neutral into first at a stand still.

The next time I made a similar mistake the CEL light came on; This time it said it was the passenger side upstream sensor.. So I just cleared the codes, to see if it would come back on. To this day (it's been almost a month) the light hasn't come back on.

And most recently this happened again a week ago where the car buckled after I shifted into first.. the CEL came on again. I read it, and it was something completely different.. P0030 HO2S Heater Control Circuit Bank 1 Sensor 1 .. I cleared the code again just to see if the CEL light would come back on.. Has not come back on to this day.

In the past when I had the CEL come on and I clear the codes. It will eventually come back on if the same problem exists. Plus if it was this easy then I imagine people would never have to tune their car with LTH etc. and just clear their codes before their smog test.. I could be wrong of course but I am pretty sure this isn't going to work.

The issue with me going from a standstill into first is not like when I'm at a stop light or anything. I have zero problem getting in gear and going. The problem is when I'm in a parking lot and I'm not trying to launch the car super fast.. It seems to me impossible for me to actually put it in 1st gear and go slow. I feel like it almost always wants to stall. Same with reverse.. But in reverse I always ride the clutch when backing up coz reverse seems even more powerful than 1st, and when I let off the clutch the car launches really fast in reverse, faster than I'd ever want to drive when backing up, so that's why I ride the clutch while backing up. Sometimes if on a hill and don't need any power once going I will shift to neutral. but yeah. I know riding the clutch is bad but slamming into a car behind me seems worse. lol

On a slightly different note but related to the same thing.. When this happens and I have my windows open, I hear the sound from the back as if something is banging in the back when the car buckles. I dunno if maybe it's that my shocks/springs are bad..The springs are definitely bad and I think the shocks/struts are worn. Not shot but worn.
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Get under the car and check for hanging burnt wiring harness. Might as well check the transmission mount while your there.
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Get under the car and check for hanging burnt wiring harness. Might as well check the transmission mount while your there.
that's as good a guess as any I can come up with!
Get under the car and check for hanging burnt wiring harness. Might as well check the transmission mount while your there.
What would I be looking for in the transmission mount? I am not even sure what that looks like or where it is.

Today the CEL came on for the passenger side upstream O2 sensor without any shifting mistakes and the light is not going off after I read the codes. It stays on which tells me the sensor does need to be replaced. So I will be replacing it.
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Although highly unlikely, I only say check the trans mount for if it's no good the transmissions tail end may move around and possibly wear on anything close to it. Plus you should be checking the wiring harnesses in that area as well for damage.
What code did you get this time? By your description it sounds like a wire or connector is loosing connection under certain powertrain load conditions.
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Although highly unlikely, I only say check the trans mount for if it's no good the transmissions tail end may move around and possibly wear on anything close to it. Plus you should be checking the wiring harnesses in that area as well for damage.
What code did you get this time? By your description it sounds like a wire or connector is loosing connection under certain powertrain load conditions.
I need to find a good mechanic. The current mechanic I got is an HONEST mechanic.. So he doesn't rip me off, and is super cool about me bringing my own parts etc. but I dunno how knowledgeable he is. I dunno if I want him messing with the transmission. How do I know if the trans mount is no good?

The code I got this time is P2251. but the light won't go away. Before the light would always go away when reading the code. There is no loose wiring with these coz I've looked at the wiring of both when the car was on the lift. coz after the mechanic put the driver's side upstream sensor on the car started making tapping sounds at high speed.. but I realized the previous owner instead of replacing the stone guard (it's this rubber/ plastic thing that connects to the bumper assembly to protect the engine from road debris) they put self tapping screws in it and screwed it into some other plastic thing under the car that it's not supposed to be screwed to, and I guess when they changed out the O2 sensor it got lose and the tapping sound was the self tapping screws tapping on metal as the stone guard flapped uncontrollably at high speeds.

I removed most of the screws btw, but there's still some tapping. A new one of those costs $180 so I am not in a huge hurry to get it. The one that's on there does its job but with the tapping.

But seeing that the mechanic got defensive when I pointed out the noise after he replaced the O2 sensor and he either didn't know that the screws were causing the noise or he didn't care to explore enough to find out is the reason why I'm looking for a new mechanic.
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I need to find a good mechanic. The current mechanic I got is an HONEST mechanic.. So he doesn't rip me off, and is super cool about me bringing my own parts etc. but I dunno how knowledgeable he is. I dunno if I want him messing with the transmission. How do I know if the trans mount is no good?
He’s not really going to be “messing” with the transmission much. Any high school shop trained kid can check and replace a trans-mount. If he’s honest like you say, just ask him about his experience whenever concerned about a particular job.
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