Electronics Problem

[MARKUSIUDIUS]

Can all the electronics dudes Help me in the JDM section please.

[MARKUSIUDIUS]

At the moment I have not received much help in the jdm section. The question is will a distributor from a different country affect the rev limiter point. They look the same on the outside but internally if the coils are slightly different etc the ecu might read it is redlining when really it is only at a lower rpm. Does anyone have a clue on this?

[Moppie]

G'day mate.

The rev limit is set by the ECU, not the dizy. (mechanical systems use a set up in the dizy, but Honda's are a bit more sophisticated).
And since the dizy has to work at exatcly half the crank speed (they are generaly run off a cam), you could stick a dizy from a nissan in there, and it would still send the same RPM signal to the ECU.

Any differnces in the Coil pack, or dizzy will be from different years and engine versions, and not what country its from.

[MARKUSIUDIUS]

Thanks but it does not solve my problem. I rebuilt my engine, we kept stock internal but nitrated them, we lowered the compression ratio to 9:1 with a 2mm (80 thou) head gasket. The car wasnt running which we found was a faulty distributor (jdm) so we replaced it with another. the car now hits its rev limiter at 6700 rpm and the knock sensor light is showing even after resetting it and it comes on without positive pressure. I am racing at Phillip Island on Saturday and Im pisssed. Is there another way to raise the rev limiter. I have a piggy back on it set at 9000 rpm but its not doing shit. Can i divert the signal somehow or cancel the rev limiter all toghether???

[Moppie]

Sounds to me like its running in limp mode.

It then runs the lower rev limit (it will also run it when its cold, or when VTEC is not engaged) and disables a few other sensors and VTEC.


Either the Dizzy you have used it not exactly the right one, or there is another fault in the system somewhere that is causing the problem.

Check the ECU for trouble codes, and check things like the wiring etc on the knock sensor. (I assume you mean the Check enigne light when you say knock sensor light)

The rev limit can only be changed by chipping the ECU, or running a piggy back, all of which are well above and beyond what you need.


What dizzy did you put in to replace the orginal one?
Its not common for the dizzys to fail.

[MARKUSIUDIUS]

The car runs fine, its as fast as always but he rev limit situation is screwed. The ecu codes when checked number 23 knock sensor and thats it. The distributor is from an Aussie vtir and the old one is a jap dissy. I will book it into honda for a systems check and replace the knock sensor. But i dont believe they will do f--- all. Thanks for youre time.

[Moppie]

Honda will do exactly the same thing your doing, check the ECU, then replace the knock sensor.


I would check the wiring to it, and the plug on it first.
Its quite easy when removing and reinstalling an engine to knock a plug, or loosen a wire in one so its not making proper contact.
I would go over all the wiring before I took it to Honda, then replace the knock sensor if that proves fruitless.
When you get one, try and ask for a trade price, or even hunt around for a 2nd hand one if you can, they are not cheap.

What year was the VTiR you took the dizzy out of?
If your is a 94 then its a 4g correct? and all the Aussie VTiR's will be 5gs???
If so then there will be some differnces that could account for your problems.

But generaly the dizzy sends a pulsed signal to the ECU based on the firing of the coil. This signal should be exactly the same no mater what the enigne is (as long as it has 4 cyl) .

Do you know if the VTEC is engaging? this will be another way of telling whether its the knock sensor that causeing the problem or the dizzy. since the dizzy wont effect its engagment, infact by the sound of it should engage early, but if its the knock sensor throwing the ECU into limp mode it won't engage.

(and how I wish I had an engine that go to even 6,700rpm again)