Good Afternoon,
My car recently got a code for the camshaft sensor after my car died in the middle of street and the engine light turned on. I had gotten it replaced. In fact, I had both (left and right) camshaft sensors replaced and we changed out the crankshaft sensor as well. Then, a new problem comes up.
My car does not accelerate as strongly as it used to. In first gear (car is automatic), my car seems to struggle to get in 2nd gear. Imagine the feeling of your car when you keep it in 1st gear (in a stick-shift) and you KNOW that’s the point of having to shift into 2nd, but you keep driving anyway. Then, once it does shift gears, my car jolts forward with a big drop in RPM. Imagine the feeling of finally shifting your manual transmission into 2nd gear and feeling that “relief” in the engine as it doesn’t seem to struggle anymore. What’s worse is that at higher speeds/gear my Pathfinder won’t go beyond 4000 RPM. I’m driving at around 65 mph and the car is at 2500 RPM. When it hits 4000 RPM, the RPM just ticks before it and my car stutters back and forth as if I’m playing a beat with my car by hitting the breaks.
An example scenario, I’m driving on the highway and there’s a slower car in front of me. I just want to pass the person and be on my way but as I press on the gas, my RPMs don’t really increase as it normally would when applying more gas to go faster. Once I do finally get to 4000 RPM, my car starts to stutter or rock back and forth as if hitting an invisible wall. Are there tons of reasons that this could happen?
On the other hand, I tested my car, in park, to see if my engine would rev pass 4000 RPM, and it does. So, the problem presents itself only when I’m driving.
Thank you in advance,
Clu3lessDriv3r
Does the rpm gauge ever rapidly increase without a corresponding increase in the speed of the car? If so, that’s usually an indication of an automatic transmission problem.
If the engine just seems to bog down for no reason during attempted acceleration, that could be caused by several things, like a sticking egr, plugged cat, etc.
One other idea, the torque converter could be going into an alternating locking/unlocking state for some reason.
Problems with the ignition system and fuel system could cause this too. Are there any diagnostic codes now?
I feel like the current issues are a result of changing out the sensors. I could be totally off track here.
But no, the rpm gauge does not increase without the speed increasing as well. If the torque converter was the issue, is that what causes the engine to feel like it’s having a hard time shifting to the 2nd gear? At this time, there are no codes nor is the Check Engine light on.
Would these parts you are referring to cause the stuttering effect at higher speeds too?
TC shudder is a common problem reported here and tends to occur around 35 - 60 mph.
It could very well be something to do with replacing the cam and crank sensors too, and unrelated to the transmission. It might be missing for example, which would cause this same type of symptom. Missing means that the explosion inside each cylinder which moves the car forward isn’t happening in one or more cylinders, or isn’t happening consistently or forcefully enough.
For that explosion to occur there has to be the correct amount and mixture of air and fuel in the cylinder, it has to be compressed properly, get a good hot spark at the right time, and the exhaust gasses have to be expelled out the tailpipe without restriction. The sensors you had changed could be affecting the spark in some adverse way. But it could be caused by any of those things above, so don’t assume it is the sensors without a proper diagnosis. Missing is usually detected by the computer, and diagnosed by a mechanic using the stored diagnostic codes.
I will have my mechanic friend diagnose for missing. I will get back to you when I get the results.
Sounds like clogged cat or fuel pump pressure. They could have left off a hose or connector during the repair.