Jenvey Tb Uning

[Guest rwh]

Hi,

 

Has anybody got any hints or tips on tuning Jenvey throttle bodies on a 2 litre Zetec(new) with Emerald ecu. The engine runs but is not smooth and on looking at the plugs its running rich. The pipes on the manifold are colouring up but strangely numbers 1 & 4 have not coloured up as much as 2 & 3.

 

Bob

[knights_templar]

Simple answer is you can't,.......unless you have some very expensive kit.

 

However, you can get close.

 

first a few questions

 

Which map are you using?

Have you calibrated the TPS?

Have you balanced the throttle bodies?

Which fuel pressure regulator do you have? Exact pressure would be good.

Are you running with a Lambda sensor? If so which one, wide or narrow?

Are you looking for performance, economy, IVA, All three?

 

From your post

 

Colour of plugs are an indicator of what was happening when you last switched off, but unlike carburettors, fuel injection can vary the mixtures and timing at any point throughout the load, engine speed, air temperature, coolant temperature and even altimeter range. All controlled by the ECU map. And that's a very basic explanation.

 

The colour of the manifold indicates heat. 1&4 are on the outside so are likely to run slightly cooler, again of no use as an indicator.

 

With the above we can probable get it smother and road going, but a rolling road session is the ONLY way to be exact.

 

Even then you will require more than one map. Performance maps are not good on economy, and you can forget IVA and MOT on a new registration. Which is the reason the Emerald can run with up to three Maps.

 

Simon