Bustang523
Junior Member
- Joined
- Jun 21, 2020
- Posts
- 9
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Hi guys new to the forum. So I picked up a 05 mustang 4.0 auto trans with 88k miles on the clock for a good deal. but after a few months of owning I'm starting to have issues. With the drive train. I was doing an 800 mile road trip and all was fine until at one point I started to hear the timing chain. when i first heard it i was gassing it to pass someone on the interstate and half way through the pull it felt like i lost all power for a brief second and i even felt the nose of the car go down. Being me I said send it and finished the road trip just fine. One thing I did notice around that time was when I pushed the engine the engine would rev to around 5k rpm but the trans wouldn't shift. The check engine light would also flash as if it were for a misfire. It felt as if the car lost all torque and the trans didn't want to shift up a gear until I let off the gas. otherwise normal driving it was just fine i could drive it just fine other than the timing chain. I figured since both issues rose around the same time the issue was that the engine just couldn't crank high enough due to the timing chain guide breaking and thus wouldn't shift unless it reached peak power.
I pulled the engine and replaced the timing chains no problem. (this design sucks BTW) when I dropped the engine back in the car the engine ran fine. after letting the chains break in I tried to do a pull. The engine revved better and smoother with no timing chain noise. The issue now is around 5k-5.5k rpm the trans still doesn't want to shift while at wide open throttle. Occasionally the engine will throw a misfire code while doing a full pull but doesn't come back after i let off.
Here is where I'm at with my thinking. Either the engine is not making peak power for whatever reason and the car doesn't want to shift until the engine reaches peak power thus no shift at WOT. OR the trans also developed an issue at the same time and doesn't have enough fluid pressure to change gears. I'm think I might have to pull the drain plug and check the fluid level but if it is only marginally low is that enough to prevent me from shifting at full power.
Basically long story short the major question is why does my car not want to shift at it's top rpm.
Thank you for any advice in advance
I pulled the engine and replaced the timing chains no problem. (this design sucks BTW) when I dropped the engine back in the car the engine ran fine. after letting the chains break in I tried to do a pull. The engine revved better and smoother with no timing chain noise. The issue now is around 5k-5.5k rpm the trans still doesn't want to shift while at wide open throttle. Occasionally the engine will throw a misfire code while doing a full pull but doesn't come back after i let off.
Here is where I'm at with my thinking. Either the engine is not making peak power for whatever reason and the car doesn't want to shift until the engine reaches peak power thus no shift at WOT. OR the trans also developed an issue at the same time and doesn't have enough fluid pressure to change gears. I'm think I might have to pull the drain plug and check the fluid level but if it is only marginally low is that enough to prevent me from shifting at full power.
Basically long story short the major question is why does my car not want to shift at it's top rpm.
Thank you for any advice in advance