Hard 1-2 shift
08-08-2014, 08:13 AM
#11
Cant this thing go faster
Thread Starter
IIRC about 14v at idle, but I will take a meter to it this afternoon to verify. I'm using Castrol transmax Mercon V for the flushes.
A couple other things that might help: It has the slight rough idle that is common for the 4.6, but I think this is caused by the FPDM. I tried to reset the computers by disconnect the battery. This made the symptoms go away for a couple of short drives last night but its back this morning. The good news is that it only happened once when I was accelerating during a right turn.
A couple other things that might help: It has the slight rough idle that is common for the 4.6, but I think this is caused by the FPDM. I tried to reset the computers by disconnect the battery. This made the symptoms go away for a couple of short drives last night but its back this morning. The good news is that it only happened once when I was accelerating during a right turn.
08-08-2014, 09:55 AM
#12
IIRC about 14v at idle, but I will take a meter to it this afternoon to verify. I'm using Castrol transmax Mercon V for the flushes. A couple other things that might help: It has the slight rough idle that is common for the 4.6, but I think this is caused by the FPDM. I tried to reset the computers by disconnect the battery. This made the symptoms go away for a couple of short drives last night but its back this morning. The good news is that it only happened once when I was accelerating during a right turn.
When's the last time you changed the plugs and cops?
Misfires feel just like a tranny issue, they can be very misleading..
08-08-2014, 10:07 AM
#13
Cant this thing go faster
Thread Starter
Plugs were replaced in March with new boots and springs put on the COPs. Also, when it happens while turning, it only does it on right turns. Would a misfire be the cause if it happens while going straight and the tach shows the RPMs going a little higher than the normal shift point then it shifts hard into second?
Last edited by technokami; 08-08-2014 at 10:09 AM. Reason: Words, how do they work?
08-09-2014, 08:55 AM
#14
Plugs were replaced in March with new boots and springs put on the COPs. Also, when it happens while turning, it only does it on right turns. Would a misfire be the cause if it happens while going straight and the tach shows the RPMs going a little higher than the normal shift point then it shifts hard into second?
Its sporadic occurrence makes me still think its not the transmission. I would still evaluate the charging system, the coil on plugs, the TPS and throttle body controls, and even quite possibly the brakes.. If it does turn out that non of the above are your issue, then I would certainly switch my focus to the transmission valve body..
08-09-2014, 10:38 AM
#15
It sounds like you have Sticking or damaged check ball-valve or
Sticking 1-2 shift valve. From what I have seen most of the time it's the shift valve in the valve body. That is the one that gets used the most and just wares
out over time. you can find a good rebuilt one on ebay and comes with everything you need. They are not hard to replace. you don't have to drop the trans out of the truck.
Sticking 1-2 shift valve. From what I have seen most of the time it's the shift valve in the valve body. That is the one that gets used the most and just wares
out over time. you can find a good rebuilt one on ebay and comes with everything you need. They are not hard to replace. you don't have to drop the trans out of the truck.
08-09-2014, 12:58 PM
#16
Cant this thing go faster
Thread Starter
A misfire will feel like a stumble or tremble.. If its over-revving and then shifting at low cruising speeds then it could still be the TPS, or even the accelerator peddle... Have you tried disconnecting the battery yet for a PCM reset?.
Its sporadic occurrence makes me still think its not the transmission. I would still evaluate the charging system, the coil on plugs, the TPS and throttle body controls, and even quite possibly the brakes.. If it does turn out that non of the above are your issue, then I would certainly switch my focus to the transmission valve body..
Its sporadic occurrence makes me still think its not the transmission. I would still evaluate the charging system, the coil on plugs, the TPS and throttle body controls, and even quite possibly the brakes.. If it does turn out that non of the above are your issue, then I would certainly switch my focus to the transmission valve body..
What signs of trouble should I be looking for in the charging system, throttle body and accelerator?
As for the valve body, it might be the cause but the PCM reset makes me think especial is on the right track. It seems the PCM is learning to shift a little later and hard to compensate for something.
08-09-2014, 05:34 PM
#17
I disconnected the battery Thursday night for about an hour to reset everything. This made the problem go away or at least way less obvious for the two short test drives I did afterwards. Friday morning it was back and doing the same thing again. What signs of trouble should I be looking for in the charging system, throttle body and accelerator? As for the valve body, it might be the cause but the PCM reset makes me think especial is on the right track. It seems the PCM is learning to shift a little later and hard to compensate for something.
The TPS sensor is still the only part I'd go ahead and throw at that throttle body since it is what I would consider a wear item... The slight rough idle IMO is the other clue that leads me to believe that something on that throttle body is the cause of your issue...
I say just try a new TPS sensor and see if it works.. If it doesn't work you can always return it.. It's around $40 for a new one.
08-09-2014, 06:03 PM
#18
Cant this thing go faster
Thread Starter
It might be $40 for you but here in Canada they go for $120, good thing I live close to the border. Should I go with Motorcraft or is aftermarket OK for the TPS?
08-09-2014, 06:49 PM
#19
Senior Member
A lot of places won't take returns on sensors and electrical components. I would check the return policy before buying. Just a heads up from my personal experience.
08-09-2014, 09:59 PM
#20
That sucks.
Motorcraft or Standard.. Preferably motorcraft... I've had good luck with returns at autozone and advanced auto.
Buy online with coupon codes at advanced auto and save a lot of money.. I usually buy a few extra things I normally need and get the price up so the bigger coupon codes work..
HUGE50 and TRT41 are good codes for orders approaching $100 or more..
WD32 is 35% off any purchase..
Motorcraft or Standard.. Preferably motorcraft... I've had good luck with returns at autozone and advanced auto.
Buy online with coupon codes at advanced auto and save a lot of money.. I usually buy a few extra things I normally need and get the price up so the bigger coupon codes work..
HUGE50 and TRT41 are good codes for orders approaching $100 or more..
WD32 is 35% off any purchase..
Last edited by Especial86; 08-09-2014 at 10:01 PM.