Howdy folk, we back with another day in the life of a TL user. Issues have risen once more.

So for about 3 weeks now i have been experiencing a noticable loss of power leaving a stop, to the point where it doesn't feel safe to pull out without a completely clear lane free. It started off when i got a check engine light for the camshaft position sensor and the car was in limp mode, i cleared that and it was driving fine for a week-ish. It never came back no other codes have appeared either.

So once this problem started getting more frequent i figured let me start with the most obvious issues with the car rather than spending so much on the sensor and the painful work of doing that repair, so i checked others sensors, vacuums, i replaced my pcv valve because it was leaking, found out all three of my rear spark plug tubes were filling with oil so i fixed that as well, also tried multiple ecu resets.

So at this point i must fall back on replacing the cam sensor...... Did not solve the issue either as i had feared, I'm not really sure where to turn at this point as I've stumped multiple mechanics with this issue and have just proceeded to replace what seemed like the obvious solution to no avail. I should note my battery voltage stays between 13-14v while driving as it should. If anyone here might be able to help a brother out, please do. I'm at a loss here

 

do you have a scanner? Looks at your short term and long term fuel trims. Look at the air flow sensor and let us know what it is reading.

Is your TL burning oil? Does the exhaust smell like rotten eggs or fuel? Hows the oil and trans fluid level? It could be your trans failing so check the fluid, should be bright pinkish red.

 

So, STFT stays between +2 and -7 anywhere between and the LTFT usually stayed around 0 to -6, both bank 1 and 2 are reading the same steady. MAP sensor reads 11 inHG at idle usually.

Not burning oil and no unusual smells from the exhaust, my pre cats are gutted and my 3rd cat has the delete from the PLM j pipe. Oil changes about 2 weeks ago it's still good, trans fluid is a darker than ideal but as for shifting and such it all feels fine and doesn't feel like it's slipping (when it struggles to take off the rpms don't climb freely so I don't think that would be slipping?) but I'm not a trans expert myself i just feel like the engine isn't making the power to spin and let the rpms climb as it should but once i get past a certain threshold of rpms it starts to pull as if nothing was even wrong with the car.

I checked my tps % as well just in case maybe that was reading wrong and causing the ECU to tweak out but that seems to be accurate and my throttle plate opens freely.

Edit: Best way i could describe the feeling is like imagine trying to take off with strong wind pushing straight against you, seems like it just doesn't have the power to push past until the rpms get higher

 

Auto or manual?

If auto, you already know the answer.

 

Lol so with the only two symptoms being darker fluid and occasionally slow takeoff we are gonna say the trans is dead? Idk. I can add now that this issue isn't present with the ac off. Yes i know ac can rob you of power yea i get that but this is not a normal robbing of power from ac feeling at all

 

I mean, failing to accelerate at a moderate rate, to the point where you said "doesn't feel safe" is a pretty huge symptom.

Are you burning any oil?
A compression test, and further more a leak-down test, will tell you the overall health of the engine. That should direct you which path to venture down; engine or tranny.

 

Yeah that sounds reasonable and I'll get around to doing that when i get a chance. Any idea why it still pulls hard in higher rpms like nothing is wrong? As well as it not being repeatable with the ac off? That does seem more like something engine related wouldn't it?

 

Well since it doesn't do it without the AC, I would start there. It could be the AC Clutch is seizing up causing a drag on the serpentine belt. Higher RPMs could compensate, which is why you don't feel it at higher RPMs.

Here's what I found after a quick search:

https://forum.allaboutcircuits.com/t...ched-on.32468/

https://www.quora.com/How-do-you-fix...n-the-AC-is-on

 

Gotcha, thank you 🙏 gonna give that a look this weekend hopefully. I will add my serpentine belt has been a bit worse for wear so on break at work today i replaced it and I haven't had a chance to drive it yet but i can say i have a voltage meter and when my ac was on full blast idling with my phone connected to the radio (every other accessory like lights and such was off) my voltage stayed low it was 13.1-13.2 and if i added anything like turning full lock, turning on lights, music the voltage would drop to mid-low 12v. Now after replaced idling with the ac on it stays around 13.4-13.6 and doesn't seem like it drops below 13 with any extra load so maybe that could be something of value? Not sure but i figured i would throw this information out there..

 

I second this....