Poor acceleration and lack of power in Jimmy

Hello guys

I would appreciate some help
 
I have a Suzuki Jimny 2011 model (M13a) with manual gear box, I had it for 10 years with minimal problems , recently I noticed the car started to hesitate and stutter during acceleration (the RPM goes up to 3000 and more for 1-2 sec then go back down to normal and the car accelerates normally afterwards)

More recently the problem became worse, now the acceleration is more sluggish, the RPM goes way high (3000-4000) for the car to start responding to acceleration (even that takes a delay of few seconds on high RPM before responding), moving from full stop is difficult and slow , and even reverse has the same problem of barely moving so slow.

Here what I did so far:

1. I changed the spark plugs
2. I inspected the spark plugs boots and wires and found that one of them had a melting wire , so I changed both spark plugs boots and wires
3- I quickly tested the coils , I removed the wire connected to first coil when the car is running and immediately the engine started vibrating , which return to normal when the wire is plugs back, I did the same process for testing the second coil, both seems to be functional using this method.
4- I changed the air intake filter with a new one, the old was pretty dirty.
5- I used fuel injectors cleaner in the tank and followed the instructions on the product
6- I removed the air intake house and cleaned the throttle body with the car off, using a carburetor cleaner then drove the car for a while 

Non of these seemed to work, it actually got worse after doing all of these

I'm thinking it might be a blocked exhaust system / catalytic converter? 
or could it be clogged fuel filter in the fuel pump assembly? or weak fuel pressure produced by the fuel pump?
Could it be the ignition coils are functioning but not properly? 
Any suggestions, what can I do next, the car is becoming undrivable
Thanks in advance 



 

For the revs to go up without the car moving accordingly it suggests the clutch has gone.

But it is shifting properly into gears when moving , and also engages and disengages the clutch when moving or stoping

Yes it will do, but it is clearly slipping when a load is applied. It's the only way the engine revs could rise without the car accelerating.

It will do that.  Disengaging is not a problem, so you can change gear, but full engagement is.

Definately clutch slipping, it will be worse in high gears where the load is more. Do you get a squeal or screeching sound when it happens?

I am not sure how many miles your Jimny has done, but a slipping clutch only goes one way, it gets worse, as the clutch slips it creates even more wear so the worse it gets with every slip.

If it is just slipping with no unusual noises it will just continue to get worse until the car won't go anywhere or at least only very slowly. If you have a variety of noises then it is likely it will get very worse all of a sudden as the clutch fails, then you will need a tow truck.

Robin