Car will not go past 4kRPM in 4th gear.

[S_Ranger]

I was doing a test the other night and I dropped it in 4th going 70. Turbo spooled fully but the tach wouldn't go past 4kRPM. Anyone know the reason for this?

 

[S_Ranger]

 

[Vexiis]

I dont think its a very good idea to downshift like that at higher speeds but I could be wrong.
On a similar note something I have noticed with my car is this:
Whenever I am going through the gears and am accelerating there is a point where the car almost loses power, im not sure if this is the turbo kicking in or what, but similar to yours in 4th gear it is about 4k RPMs. I notice it in 2nd through 4th though, 2nd at about 26 to 30 MPH, 3rd about 40MPH, and 4th about 4k RPMs (never paid attention to the MPH on 4th).
it is strange but it basicly feels like the car wont go any faster and it loses power, then I shift to the next gear up and its fine.

As for your question, rev limiter maybe? I wouldnt think it would be that low but I cant think of anything else that would stop the RPMs.

 

[v8s_are_slow]

I dont think its a very good idea to downshift like that at higher speeds but I could be wrong.

um, 4th gear at 70 mph isn't fast.

but anyway, is it only doing that in 4th gear? but maybe check for boost leaks. having any other problems? need more info.

 

[spoolin_upTSi]

To Vexiis:
I had a similar problem in my 3000GT. Turned out to be the ignition. It was either the plugs or the wires (don't know which because I changed them together). Dont just run out and buy them though. Let your car idle and pull your wires one by one and see if you aren't getting spark on one of the cylinders (your car will sputter like hell if the cylinder is ok).

To Ranger:
Is the car pulling all the way? Does it seem like the whole engine is stopping or is it just the tach?

 

[S_Ranger]

The whole engine...

 

[out there]

does it do this in every gear? all the time, or only during certain weather conditions?
my saturn did this for a while, and it turned out to be crappy plug wires/plugs. try changing those first, because they are the cheapest way to fix the problem that it sounds like you're having.

fyi, downshifting into 4th at 70 is nothing... just make sure you rev-match and preferably double clutch; your transmission will thank you