Swap JECS for Bosch Throttle Body?

Hi All,

I know there are lots of threads about throttle bodies, but haven't found an answer to this question.

I have only basic mechanical skills, but after just buying my 2000 k11 March auto, I'm already being driven crazy by poor fuel consumption (28mpg) and a really bad shudder in reverse and drive.

I resoldered the throttle body and gave everything a good clean with electrical cleaner (that doesn't leave residue) but things are as bad as before.

I am going to get a service of all filters etc soon, but I'm almost certain the throttle body is still the problem.

The car has the old JECS style throttle body, do I have to replace this with an identical unit or can I straight swap it for the newer bosch type throttle body? Is that even worth doing?

Appreciate your help!

the bosch t/b has a different footprint/bolt pattern affroken, and a 5 wire connector for the maf iirc, and a stepper motor idle control valve.
28mpg does,nt sound too bad for an auto

Hi Frank,

Thanks for the info, I'll look out for a JECS throttle body. Really appreciate your feedback.

I know 28mpg is not terrrible for most autos, but thought it would be a lot better on a little 1.0 litre model?

Also, Is it common for throttle bodies to cause heavy shuddering in drive and reverse? The idle seems to pick up in neutral and park.

Could I be missing some other issue?

i doubt if you will average more than 35mpg mate, and check that its closed looping ok (lambda voltages) before forking out for parts you dont need.
closed loop @ cruise after about 2 miles of warm-up usually rules out a lambda/coolant temp sensor/maf problem (covered by many threads on here).
the judder could be a rear mount or powder clutch issue maybe ?

Great, thanks for the info, I'll check that out.

Checked again, it's getting 21mpg not 28mpg, my math sucks - so there is definitely some issue.

Thanks again for all the help!