My 2006 Jaguar S Type R will not go past 120ish mph. It has no codes or issues and runs great otherwise. I don't typically go over 100 but discovered this on a drive through a deserted section of desert highway one day.

Any ideas?

 

Factory speed limitter?

(I hope you have tyres (aka tires) which are OK for high speeds.)

 

thanks for the reply....its an str. so the governor is supposed to be 155 and yes it comes with the appropriate tires

 

155 in USA?

When did this reduced behaviour show up?

 

you need to get an elm327 and read/watch all of your real time data , to make sure every sensor is in check . also have a look at your spark plugs , they can tell you a lot .

 

Let us know what you find?

My 2005 STR is limited to 155 MPH and it is still gaining at that point too.

I like to use the GPS speed at the same time to see how far off my speedo is.
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I have had it scanned in real time by Jaguar tech. All software is up to date. There are no codes on Jaguar scanner.

Yes it's governed at 155 in the US.

I have never had it over 110 except the one time so I don't know when it started. It runs perfectly well and pulled hard up to 120 and then just stopped accelerating.

The car is well maintained and I've never let anything go on it. Everything is maintained better than the manufacturer's schedule. The car runs fantastic except for this. It's not really even a big deal to me since I'm not intending to drive that fast just curious.

 

Scanning for codes and monitoring data are two very differant things .

 

I'd (have a passenger) watch every value especially as the problem appears.

 

Don't forget to have lookout for the police. or you be in big trouble.

 

Some where way back in my mind i remember a software update campaign being done to the ecu to address many things that updates address. And the side effect was irritable bowel syndrome and reduced top speed limiter.....shrug

 

After 2003 or 2004, the federal bureaucrats forced auto makers to limit speeds to 128 MPH. It really sucks that some sorry bureaucrat can do this "in the name of safety" but it can be undone with some computer work, as I understand it.

 

Hmmmm . . . that's one PC "safety" issue that must have got past our bureaucrats here in Oz . . . no onboard speed limiter issues but plenty of really smart "slant" radar units . . . fixed, mobile and even aerial. I think their rationale here is really smart . . . why limit the car? . . . just penalize the hell out of speeding drivers.

Reminds me of 3 specific occasions, very fast, in the E-Type in years past. First was overtaking a string of slow cars on a very lonely rural highway. Speed topped 135mph as we flashed past final car, and a roadside patrol . . . saw him don his cap . . . then put it back down as we flashed past. Second was a rear tyre blowout at 100+mph of which I was oblivious until seeing cloud of blue haze filling rear mirrors. Slowed but combination of LSD and centrifugal force kept flat tyre up and on rim until down to 30-40mph. Third was the only occasion I succumbed to the radar . . . 126mph to be precise . . . as I rounded a rare sweeper on a totally deserted 250Km stretch of country highway, to meet the oncoming patrol car rounding the opposite sweeper. Were any of these dangerous?

That 3rd naughty could have been even more expensive some 10 miles earlier when right on the limit . . . but the message got through . . . all subsequent really fast driving was confined to the track. These days, I confine myself to getting from 60 to 110Kph (say 70mph) as fast as possible, but then lift off. My halo shineth . . .

Cheers,

Ken