I have a 98 with the 4.0 and an auto. When under a load (hard thottle or climbing a hill) the trans doesn't want to shift. It will shift if you let of the gas. But around 3500 rpm the engine completly falls on its face. I took it to the local transmission shop and they think the trans probably needs to be rebuilt. Evidently i have a japco (think that is right) trans and will be 2300 or more to be rebuilt. The question i have is if it is just the trans why is the engine not still pulling strong at these rpms? I guess i am just looking for anything other than the trans to be wrong. Sorry so longwinded and any help will be greatly appreciated.
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HELP
- Thread starter joker4802
- Start date
jeepdude10000
NAXJA Forum User
- Location
- LaLa land!
Ok when your going up hill you have the thottle most of the way down, so the tranny should not shift, it is designed that way.
When there is trouble with a tranny, is when it does not engage properly or when it shifts and slips(the engine rves high then engages when shifting up).
Tell more on how tranny works when cold and level driving.
When there is trouble with a tranny, is when it does not engage properly or when it shifts and slips(the engine rves high then engages when shifting up).
Tell more on how tranny works when cold and level driving.
On flat ground mod throttle shifts fine. With higher throttle it stays engaged in each gear to long, past 4000 rpm. I pulled the pan replaced the filter and fluid, filter was clean, fluid didn't smell burnt, and no metal shavings. The reason i think it is something other than the trans is the engine falls on its face over 3500 rpm. If it was the trans just not shifting it should still pull strong. I'm going to start with the cat maybe being clogged and then on to making sure the fuel pressure is correct. Sound right to you?
- Location
- Near Rochester NY
Sounds like a good starting place to me.
jeepdude10000
NAXJA Forum User
- Location
- LaLa land!
I would check the Tv cable too, sounds like it is over tight.
lawsoncl
NAXJA Forum User
- Location
- North Idaho
You have an Aisin Warner AW4 transmission. Of course a tranny shop is going to insist you need a rebuild. Don't. First, your problem is likely not the tranny itself. Second the AW4 doesn't take well to rebuilds, even by a good tranny shop. Third, $2300 is a serious rip off.
The TV cable on the AW4 does not affect the shift points, just the shift firmness. It's easy to adjust and you should probably do it anyway. The shift points are decided by transmission computer, based on the throttle position (TPS sensor) and the shaft speed sensors on the tranny itself.
If it is not shifting correctly, more than likely, you simply have a bad TPS sensor. This is a very common problem as it is a mechanical sensor which can wear out or get damaged if water gets inside. It's located on the side of the throttle body and very easy to change. Figure about 10 minutes to change and $30-50 for the sensor depending on model year and where you buy it. I would try replacing that before going back to the questionable transmission shop.
As for the engine losing power, I start with a basic tune-up with new plugs, plug wires, cap and rotor. Especially if they've never been done. I would also consider replacing the front O2 sensor if it's still the original and you're getting poor mileage. Should be under $100 for parts.
The TV cable on the AW4 does not affect the shift points, just the shift firmness. It's easy to adjust and you should probably do it anyway. The shift points are decided by transmission computer, based on the throttle position (TPS sensor) and the shaft speed sensors on the tranny itself.
If it is not shifting correctly, more than likely, you simply have a bad TPS sensor. This is a very common problem as it is a mechanical sensor which can wear out or get damaged if water gets inside. It's located on the side of the throttle body and very easy to change. Figure about 10 minutes to change and $30-50 for the sensor depending on model year and where you buy it. I would try replacing that before going back to the questionable transmission shop.
As for the engine losing power, I start with a basic tune-up with new plugs, plug wires, cap and rotor. Especially if they've never been done. I would also consider replacing the front O2 sensor if it's still the original and you're getting poor mileage. Should be under $100 for parts.
