Sometimes hits rev limiter at 120-125mph

[mnsrt10]

hi all, question on my truck it sometimes does this and drives me nuts just knowing it does it. Wide open throttle and O/D is suppose to kick in by 120 mph and sometimes the truck will not shift into O/D on its way up in speed and it will bounce off limiter till you let off throttle a little bit and then it will shift into O/D and let you go beyond 120... any ideas??

 

[mnsrt10]

mods include: borla exhaust, k&n drop in, jtsvp throttle body, sct tuner. Rest of gears at WOT shift great no issues. Just the damn O/D shift it sometimes holds out on me and will say screw you till you let off the gas a tiny bit.

 

[caveman]

I have no idea why your truck is doing this. On a different note, you drive really fast.

 

[TheMoparConnection]

possibly just a throttle valve cable adjustment. that's what I would check first

 

[mnsrt10]

Someone mentioned TV cable before in regards to it but wouldn't that affect other gear shifts to? aren't bands used for shifts except for O/D that uses a clutch? at any other throttle shifts into O/D perfectly.

 

[Arska2]

How To reset the shifting and idle with an aftermarket Throttle Body:

1. Disconnect all three PCM connectors for about 10 minutes. By doing this, you are erasing the PCM adaptive memory. The PCM is located on the firewall directly above and behind the passenger side front wheel.

2. Disconnect the TPS (throttle position sensor) on the driver’s side of the throttle body. Ensure all wire connections are correct.

3. Disconnect the IAC (idle air control motor) on the air plenum located on the passenger side directly behind the air filter. Ensure all wire connections are correct.

4. With the PCM disconnected, make sure the throttle cable and throttle linkage is adjusted properly for wide-open throttle. The driver’s floor mat should be removed as it can inhibit accelerator pedal travel.

5. After wide-open throttle is verified or adjusted, reconnect the PCM, TPS and IAC connectors after 10 minutes has elapsed from the start of this procedure.

6. Turn the key to the "on" position, but DO NOT start the engine.

7. With the drivers floor mat out of the truck, slowly press the accelerator to full throttle, then repeat. By doing this, you are showing the TPS (throttle position sensor) full throttle. Without this information in the PCM, it will not correctly calculate how to make the engine run properly.

8. Turn the key off then start the truck without touching the accelerator.

9. Let the engine idle for approximately 2-3 minutes.

10. After idling, drive easy, then progressively harder over the course of about 10-20 minutes.

11. The truck will drive differently during the first 20-40 miles because the PCM is learning the new adaptives.

Stolen from another forum years ago and it worked on my and other trucks !

 

[shorty]

Sorry, your post was not clear to my muddy brain but when I am WOT up to say 60 or 70 and I let off the gas it keeps in whatever gear I am in for a short time, sometimes for 3-5 seconds and feels like it is hung----then it shifts. Could be this is what you are talking about. :dontknow:

 

[Arska2]

No, what i understand and what i also had is, that all shifts are fine up and down, but the shift under kick down or wot (whatever you call it) from 3 to 4 wont do and it feels like it hits the rev limiter.

When you let off gas, it shifts and you can push the pedal again.....

With the procedure above, you can solve the problem

 

[mnsrt10]

arska2 you are correct exactly what i'm talking about. I will give that a try again, thought they reset it when they put on the TB but maybe not.

 

[mnsrt10]

when you had the issue was it 3 to 4 also? seems so odd that all other gears under WOT run spot on even with the rpm climbing much faster, but 3 to 4 (O/D) is the only one that it does it with.

 

[Arska2]

Absolutely the same.

We have had 5-6 QC with the same issue here in Germany including mine.

All cured with the procedure above.

Arne

 

[VENOMOUS1 RACING]

when you had the issue was it 3 to 4 also? seems so odd that all other gears under WOT run spot on even with the rpm climbing much faster, but 3 to 4 (O/D) is the only one that it does it with.

Ok are you racing/driving fast with tow/haul engaged? Does it change when not engaged? I agree withit likely being throttle valve cable adjustment. Make a small change in adjuster then try. Mark your original position for reference.

 

[Arska2]

Its not tv cable. Tried it several times, before i unplugged everything and followed the procedure.

As mentioned before, all shifts are fine 1-2, 2-3, 3-2, 2-1.
3-4 under wot it will hit rev limiter....

 

[mnsrt10]

will try it tomm arska2 thanks, do you know if ill need to reload my tune after doing this or does it just affect the shift/idle.

 

[Arska2]

On my side, it just affected the shift/idle as it resets only the "learning" part and not the "memory" part of the control units.

If you understand my german/englisch

 

[VENOMOUS1 RACING]

On my side, it just affected the shift/idle as it resets only the "learning" part and not the "memory" part of the control units.

If you understand my german/englisch

Interesting info Arska. Your English is fine sir

 

[Pirana131313]

How To reset the shifting and idle with an aftermarket Throttle Body:

1. Disconnect all three PCM connectors for about 10 minutes. By doing this, you are erasing the PCM adaptive memory. The PCM is located on the firewall directly above and behind the passenger side front wheel.

2. Disconnect the TPS (throttle position sensor) on the driver’s side of the throttle body. Ensure all wire connections are correct.

3. Disconnect the IAC (idle air control motor) on the air plenum located on the passenger side directly behind the air filter. Ensure all wire connections are correct.

4. With the PCM disconnected, make sure the throttle cable and throttle linkage is adjusted properly for wide-open throttle. The driver’s floor mat should be removed as it can inhibit accelerator pedal travel.

5. After wide-open throttle is verified or adjusted, reconnect the PCM, TPS and IAC connectors after 10 minutes has elapsed from the start of this procedure.

6. Turn the key to the "on" position, but DO NOT start the engine.

7. With the drivers floor mat out of the truck, slowly press the accelerator to full throttle, then repeat. By doing this, you are showing the TPS (throttle position sensor) full throttle. Without this information in the PCM, it will not correctly calculate how to make the engine run properly.

8. Turn the key off then start the truck without touching the accelerator.

9. Let the engine idle for approximately 2-3 minutes.

10. After idling, drive easy, then progressively harder over the course of about 10-20 minutes.

11. The truck will drive differently during the first 20-40 miles because the PCM is learning the new adaptives.

Stolen from another forum years ago and it worked on my and other trucks !

:congrats::congrats::congrats::congrats:

 

[Psycho1122]

I'm so glad to have a manual transmission.

 

[shorty]

I'm so glad to have a manual transmission.

Hold on to your manual as an article on FOX this am said in the not too distance future there will be no more manuals. Auto's get better milage and shift a lot better than a human when set up properly. :chain: Sorry

 

[NightRunnerRC]

You should learn to drive stick problem solved lol