Suzuki Jimny 2005 automatic powerless on highway

We replaced the throttle because it had problem. We checked that with the diagnostic tool and the code was fort the gas throttle. So we replaced it but nothing happend only the lamp turned off. The only modification is general grabber at3 tires 205/75-15. There arent any smells from the gearbox, only sometimes som smell from gas. In N its revs good no problem, but when you are on the highway you cant go more than 90km/h and the car havent power to rev up more than 4000rpm i dont know if its with 3rd or 4 gear. I dont think its normal i dont know any other with automatic gearbox in Sweden. And its not big hills its very low gradient hills. Its the highway you Can not Call them hills the seller who sold the car to me told me its a new Exhaust and cat. I dont know what to do, i have booked an checkup on Suzuki 8/12.

Here is some photos of the car 

The code you have P0121 is stating that the throttle position sensor has a range problem, see the following obd2pros.com/dtc-codes/p0121/

The following text is taken from this link

Causes

There are a few primary factors in your vehicle that may cause a P0121 trouble code:

That the TPS has an intermittent up or an internal short.
That it is rubbing the harness and causing a short or open in the wiring.
There is a bad connection at the TPS.
That the PCM is bad (although this cause is less likely).
That there is corrosion or water in the sensor or connector.
Any one of these could trigger a P0121 trouble code to occur.

Symptoms

There are a number of symptoms that a vehicle may be experiencing, should a P0121 trouble code be present with the vehicle:

The check engine light comes on.
The ECM will cause the check engine light to come on. This will put the vehicle in failsafe mode, which means that it will cut off the current to the throttle actuator, put the throttle valve at a little less than 6 degrees of an opening.
The ECM with control fuel injection and timing to control the speed of the engine.
You will be able to drive your vehicle, but only slowly and with very limited response to the throttle.
The engine may not accelerate as smoothly as before.
The engine may idle higher than it normally does.


This seems to fit, your Jimny is running on reduced power or reduced throttle opening. The links suggests checking the sensor, but also the wiring.

Robin

hi and thank you very much for your help, it is very much appreciated. when the lamp was lit, the car went into safe mode, it then had no power at all and did not rev high at all. then I left the car in the workshop and they replaced the throttle house and tps sensor. if there were still problems would not the lamp start to shine again? the car has power at low speeds. from the start it is very alert but as soon as there is a small hill it loses speed.

I would try to take a video tomorrow and post it here so you can see what the problem is and how it works.

I can also tell you that the fuel consumption is very high its about 11-12L/100km with 35L i do maximum 300km.

Here is two videos of todays driving 

1. 
2. 

Unfortunately I don't have any experience of a Jimny auto, so can't really comment if what you are seeing regarding gear changes are correct. It probably is, it is changing up somewhere around 4,500 RPM.

Looking at you RPM vs Speed, it is just lacking in power, especially at the top end. There are a wide number of causes for this, too many to list here, but a Google search gives this article which lists most of them.

cartreatments.com/car-losing-power-when-accelerating/

The poor fuel economy is also a clue.

I would check the following:

1) Air Filter, is it nice a clean or clogged, this is a 5 minute job. If you can't get air in, especially at the higher revs it will limit power.

2) Spark plugs, take out the plugs and check the colour against a chart. Do they look black with soot? The plugs will confirm if your engine is running rich. Depending on what they look like will give us a clue as to what to check next.

Also check the coil packs for cracks (these can sometimes be very small, so clean the coils with contact cleaner and inspect under a bright light). Coils are under high load at higher rpm/power and a weak coil will be more of a problem at higher rpm, producing a poor spark and poor burning of the fuel. You should see this in the O2 sensor, but you need to be graphing the sensors whilst driving.

3) Exhaust, a blocked or restrictive exhaust will limit power again especially at high revs. You said the exhaust was changed, was it the whole exhaust or just part of it? Apparently the first CAT (manifold) break apart and clog the second CAT/box on Jimny's, if it hasn't been changed this might have happened.

4) Fuel. Has your fuel changed? Gone from premium unleaded to a lower octane rating or more Ethanol? Or is it just dirty fuel or water in the fuel? This is difficult to answer if you haven't had the car long and it has always been like this.

5) After that it probably gets more involved. If your engine is running rich the fuel pump + filter are probably okay, it's more likely to be air/mixture/timing.

If the filter is okay, check the MAF sensor.

Suspect the O2 (Lambda) sensor, especially as the exhaust was changed.

Timing, CAM/Crank position sensor.

Suzuki might find the problem, the trouble is if there aren't any codes, they might check sensor graphs but are more likely to start throwing new parts at it until they strike lucky, time is money to them and these problems are often difficult to fix without spending a lot of time.

Hope that helps.

Robin

Hi guys, i have now solved the problem it was the little cat with position under the engine, i mounted away the lamba and the car was like another car so i ordered a new cat with branch pipe. Thanks everybody for your inputs! 
 

Hi GeoriosP,
Glad to hear you solved this issue. Could you please put photo of lambda sensor that you replaced? Where this sensor actually placed?

Regards,
Jargal