Sportrak power delivery problem


Only had my 1993 Sportrak for a month or so.
Problem started as a dip in power at 3000 rpm, with the engine returning to idle speed without cutting out. If you keep your foot on the throttle then the revs would climb pack to 3000 then dip again and so on... Resulting in a bumpy ride!
The problem now occurs at idle, and I'm unable to get the revs above 1500 rpm.
It's in the garage but all I get from them is that the engines are usually fautless - not this one!
Any thoughts appreciated, I really miss it!

Very likely an injection

Very likely an injection system fault, it appears to be moving into limp home mode.

This restricts engine power and revs, depending upon fault,but gives you enough power to get the vehicle home, or to a dealer.

hopefully not this

i had something similar happen to mine but hopefully yours wont be the same. what happend was whomever did the timing belt before i had it didnt quite know what they were doing and the main cog that drives the belt sripped most of its main tooth (bit on the inside) which resulted in it skipping a couple of teeth. put my timing well out and would barely pull the skin off a rice pudding. however when it happend it made a load of noise. hopefully yours turns out to be an electrical fault.

Thanks for both of

Thanks for both of these.
There was no major noise and the problem is only sporadic so I hope it isn't as major as this last comment sounds.
I'm going to try a major service, and a clean out of the throttle housing and injectors and see where I get from there.
Any more information will be greatly appreciated,

From your description it is a

From your description it is a sensor intermittently breaking down, the most likely is the temperature sensor. This would default and throw it into limp home mode.

Any of the major sensors being defective would stop the engine totally.

Check for earth faults on the various systems, particularly the coil and ignition amplifier, corrosion hits many people during this weather. Salt gets into the vehicle and this corrosion forms where components earth, giving a bad earth, or high resistance.