Drove from Michigan to Toronto, car drove fine except for some slight hesitation just before we arrived. While in Toronto, car was driving fine, and coming back, just after crossing the border it start hesitating again, especially while letting go off the accelarator but after around 30-40 miles it start hesitating even at constatnt speed and than the car start intermittently shifting from 4th to 3ed geer, while at constatnt speed of 70-75 on a flat road not going uphil. The shifting problem got worse and than after around 20-30 miles the M&S light, the D (drive indictor) TC and downhill assisst light came on and was flushing. Got off the free way and the engine stalled. When I restarted everything was fine, no more flashing lights and the Ultragauge pulled one pending code (P0123). Luckily I was very close to home and took surface streets to get home and the car drove fine.

As far as the hesitation is concerned, I have experienced this also in the past, only at highway speed and especially while letting the pedal go a little, it feels as if fuel is cut off to the engine for a split second. This was an intermittent problem and I never had any codes

The Code seems to be related to throttle position sensor, do you guys think that changing the sensor will solve the problem?

 

You need a new battery or alternator, when the battery voltage drops to low (13v?) the transmission goes into limp mode, that means 3rd gear only and the "M" and "S" lights will come on.
Turning the ignition off and back on resets the trans computer, if the problem is severe enough that will not work.
Sooooo, have your battery and alternator tested.

 

I did not check the voltage yet, which I will do, but my car was just shifting in and out of the 4th and 3ed, not staying in 3ed.
And even if parked for 2 weeks it starts after first crank, so I am no sure about the battery.
Some further rading on the net indicates that hestation at idle is also one of the symptoms of a bad throttle position sensor, which I had intermittently in the past.
And to just make things more interesting our other car doesn't start, I think the interior light was left on, when we were gone, battery is dead and the way it is parked I can not get the landrover close to it to jump start it and the car is not going out of park to move it.

 

How do I test the alternator?

 

Just watched a vieo on you tube for alternator check, will do it soon. Thnaks Spikefor pointing this out

 

If the alternator is marginal a long trip can drain the battery down to a point that it will cause trans ecu problems.

AutoZone can check the alternator for free.

As for the other car, use a battery charger, or take the battery out of the car and attach the jumper cables to it from the Rover, let it charge for 15-20 min and then put it back in the other car and start it up.

 

Your voltage must be between 13.6 and 14.4. As for your TPS, you do need to replace it.

 

Thanks Spike, I had a brain freez and was on my way to walmart to get another jumper cable when I read your post. I actually removed the battery from landrover and jump started the other car and put the battery back in.
I also checked the battery and alternator and got these numbers
battery voltage is >12.92
When the car is runing voltage is greater than 14.2
when I turn on the headlights, front and back fog lights heat at full blast and one of the blinkers it drops to 13.92 and above.

Do these numbers rule out battery/alternator failure?

 

Thanks Mike, voltage seems to be fine, I was searching ebay and found TPS ranging from just over $18 to almost $200. Will check local stores in am and see if they have any. It looks like they are interchangable with alot of cars. See this ebay listing:
1997-2007 Hyundai Kia Saab Land Rover Cadillac Throttle Position Sensor | eBay

 

13.6-14.4 is the alternator check, when the car is running, right?