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Evening all,
Just had a question about something I noticed my car doing.
When cruising around I can hear and feel the car go from 1st to 2nd to 3rd fine, however.. when it goes into 3rd its a really deep low tone, as if it's dropped too many revs, after it picks up it then goes into what sounds like 4th... but then at about 70ish it then goes into another gear...
Aren't the VT boxes a 4 speed?
I'm not sure what it does under heavy throttle because I don't get much of a chance to do that on an open road.
Does anyone know what might be causing this 'extra' gear around 3rd ? if this isn't normal of course.
thanks
Could be the overdrive, or the torque converter clutch locking up
Cheers shade,
Further to the above, the car this morning has changed. It's now holding first till about 2-2.5k RPM and then when it DOES actually shift, it shifts hard with a jolt through the whole car.
Something's obviously up big time. Seems to hold second a bit too, but my run to work doesn't allow me to get much speed up at all. Very stop start.
Anyone have any further information, especially now it's starting to jolt severely ?
Could it be something wrong with the gears themselves or possibly a gear selector or even something completely different ?
I think it's actually jolting harder than it would if I was to manually shift the gears too.
Yeah sounds like its got issues. Check this thread 4l60e Problems and Solutions
I think the V8 is the 4L80E but it should help in diagnosing it...
Oh yeah and check the condition of your tranny fluid, if it looks brown and smells burnt then its had it
Ah, legend. Cheers.
Looks like I should check the TPS by the look of it!
And on the way home the car was basically driving fine, the only difference is that at idle it seemed to sit a bit higher than normal.
Might change out the TPS and IAC Valve and see if that works. If not I might have to change the TB or something perhaps back to standard. (or look for other issues).
Will be sure to post an update on this as soon as I can.
It's beginning to really tick me off. Have a spare TPS here that I pulled off when I did the MACE 70mm TB change over and replaced with the one I got with it.
had to use the old IAC valve, I've ordered a new one though.
It's now doing it for pretty much every gear, only the higher gears you don't notice it as much on the change, other than it holding the gear for far too long when you're just cruising.
2.5-3k changes when you're just putting along normally is such an annoyance.
Uh... before you go to far... the torque converter lock up also reduces revs and can feel like a gear change - especially if your gearbox has been modified to increase line pressures. the 4L60E can feel like a 5 speed because of it. Normally the torque converter will only lock up in 3 and 4, unless you drive the gearbox manually.
When you say lock up, what do you mean exactly?
I should be swapping out the TPS etc tonight to see if that helps any. Really hoping it does.
It seems to have the same symptoms that are noted on #27 in the link shademechanic posted.
Likes Shiny Things
Torque converter lockup refers to the engagement of the clutch in the torque converter. When it's engaged the clutch locks both sides of the torque converter so that they rotate together. When both sides are locked together the transmission is rotating at the same speed as the engine. It provides better fuel economy at cruising speed.
As said above it can feel like another gear has engaged particularly if your line pressure has been increased or if the restrictive cap at the end of the input have has been removed.
1. 1990 VN Exec V6
2. 1993 VP BT1 3.8L - Now wrecking for parts!
3. 1991 VP Berlina V8 - RIP
Looking for a good condition VN - VS V8!!!
Ahh wicked, cheers.
I ordered a new PCM hose... does that sound right?
Anyway its the hose from the throttle body to the rocker cover.
quite thick with some weird metal thing on it.
Mine has a small split in it, would this cause many issues ???
Id say you mean the PCV=Positive Crankcase Ventilation hose.It will cause the engine to run a bit crook if the hose is split and it is sucking air in through it.
Ah cool, I guess replacing it's gonna be a good thing then
Okay PCV, TPS and IAC fitted, seems to have fixed all the issues I was having around the ####ty shifting and varying idle.
Car still does a random 1 off idle fpm increase then decrease and then it's fine. Not sure if this is standard, but I can deal with it nevertheless.
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