2.2l C5 X7...Revs limited.

[qprdude]

I've only had the car since June 1012 so it's a little early to have noticed some things.

Having had a battery/starting problem recently, I've begun to take a little more interest when starting the car.

What I've found is that the engine will not rev above 3000rpm in neutral. I thought it was the dreaded "limp mode" but there were no fault warnings. This was in my driveway, so I took the car out and gave it a blast. The revs went right up to the red, with no problem. When I got back home, I tried again and the revs climbed to 3000 and no further. It's just like when you have a rev limiter, but only in neutral.
I wonder if anyone knows if this is normal for the X7 2.2 HDI engine.

[vborovic]

I can try doing the same with my car tomorrow, I think I can rev mine over 3000 in neutral, but will check just to be sure

[qprdude]

Cheers mate. Appreciate that.

[daviemck2006]

I seem to think that my c4 vts does that. If it's not the c4 then it's something else I've driven recently. I'll check the c4.

[addo]

It is deliberate. There is no real need to rev madly; such things as DPF forced regeneration are separately driven.

[qprdude]

I seem to think that my c4 vts does that. If it's not the c4 then it's something else I've driven recently. I'll check the c4.

Cheers. I'm just confused. The rev limit must be linked to the gearbox then? I understand it's not good practice to rev the car too much from idle, but I had left the car running for a while to put something back into the battery (I hope) and thought I would give it a bit of a rev up, then let it idle before shutting it off.

[Xantidote]

to put something back into the battery

I have a Ring digital voltmeter which I plug into the cigar lighter, and been using it recently, partly as I've just replaced worn out 80 amp alternator with my spare, which (alas) is 70 amp. My observation FWIW is that, based on the voltage displayed, the alternator is putting out quite a good charge at tick-over, and the voltage hardly increases when revved even to (say) 1500 rpm.

[vborovic]

Ok, so I've tried revving today, cold start, automatic 6-speed gearbox, both in P and N, I could reach 4500-5000 rpm, no problems.

[qprdude]

Cheers for that.
I've just checked again with the car stationary, and even more strange.
in neutral max 3000RPM
In 1st gear, clutch depressed Max 3000 RPM.
In Reverse gear, clutch depressed Max 2500 RPM!!!

Figures are the same with the electronic hand-brake on or off.

[daviemck2006]

The c2 vtr revs all its rev range in neutral. Havent tried the c4

[vborovic]

Maybe there is a difference in the manual and automatic gearbox, but it would have more sense to me to limit the automatic gearbox than the manual one ... I''ve stumbled upon a similar discussion, maybe some pointers there: http://www.saxperience.com/forum/archiv ... 92840.html" onclick="window.open(this.href);return false;

[qprdude]

That sounds like petrol cars though.
The confusing thing is, the car accelerates like a rocket through the gears and the revs go all the way up when asked. This only happens when the car is stationary. Weird

[Hell Razor5543]

I wonder if it is because the engine could rev so freely it could red-line in next to no time, so they have limited it when not under load. How quickly does she accelerate? You suggest she goes through the gears like a rocket.

[vborovic]

The only cars that I know of that have sophisticated rev limiting are the Mitsubishi EVOs (launch control and other gadgetry are linked with all that), don't see the reason anything like that would be put on a family car (well, at least definitely not a rally-sports car) ... if it would be a mechanical fault, I doubt it would be that precise (exact 3000 RPMs everytime) .... maybe it is BSI related? Lexia debugging maybe helps, if it bothers you ... btw, I can't wait to get my hands on a Lexia, I'll practically move into the car from the house ... ...

@ razor - How do you explain my car not doing that? My 2.0L engine is the newer date as qpr's 2.2L ...

[qprdude]

Not Ferrari performance, but through the gears she picks up beautifully and except for 6th gear, the revs go all the way . (I'd probably have to be at over 130 to get the revs up in 6th)
There's no hesitation in any gear and although the car is only 173, it feel a lot more powerful. You raise a very good point there, because the revs go to the red very ,very quickly in first and second.