I learnt an unfortunate lesson from buying a second hand Unichip A. My car wouldn't idle properly after it was installed. It ran rough and nearly stalled when idling.

After taking the car back to the tuner, they told me that the early Unichip A's are known to fail in the circuitry used for the MAF intercept. He had a few units fail over the years.

Eventually, my tuner sourced one of the last of the new Unichip A's available and installed it. We went this way so that he could reuse the installation and the tune. If I went for a new Unichip Q, I would have to have paid for a new installation and tune. The car now idles properly. But it cost me an extra $100 dollars over what I would have originally paid for it had I just bought a new Unichip Q and had it installed.

So, if you are looking at Unichip A's be careful, make sure that it is either been running correctly in a Magna or that it is a "late" model unit. What constitutes a "late" model unit I'm not entirely sure, but mine has mounting ears on the case.

Be warned.

Ken N

I learnt an unfortunate lesson from buying a second hand Unichip A. My car wouldn't idle properly after it was installed. It ran rough and nearly stalled when idling.

After taking the car back to the tuner, they told me that the early Unichip A's are known to fail in the circuitry used for the MAF intercept. He had a few units fail over the years.

Eventually, my tuner sourced one of the last of the new Unichip A's available and installed it. We went this way so that he could reuse the installation and the tune. If I went for a new Unichip Q, I would have to have paid for a new installation and tune. The car now idles properly. But it cost me an extra $100 dollars over what I would have originally paid for it had I just bought a new Unichip Q and had it installed.

So, if you are looking at Unichip A's be careful, make sure that it is either been running correctly in a Magna or that it is a "late" model unit. What constitutes a "late" model unit I'm not entirely sure, but mine has mounting ears on the case.

Be warned.

Ken N

Was this tuner in the south of Melbourne or the East?

That sounds very odd to me,as The unichip only works after closed loop,ie after the throttle is open and should not effect any closed loop operation which includes idle,so got me buggered though,if it had faulty MAF circuitry,surely it would be impossible to tune,as this would control the mixtures across the board?

That sounds very odd to me,as The unichip only works after closed loop,ie after the throttle is open and should not effect any closed loop operation which includes idle,so got me buggered though,if it had faulty MAF circuitry,surely it would be impossible to tune,as this would control the mixtures across the board?

This is directly from the website.

How does Unichip increase engine power?
Every engine requires optimum ignition timing and air fuel ratio at all RPM and load conditions. unichip gives the experienced Dynamometer technician the access to and ability to adjust and optimize both the ignition and fuel system. Unichip has 17 RPM sites between 500 RPM and 8000 RPM and 12 load sites between zero throttle position and wide-open throttle position. This equates to 204 possible adjustments for fuel and a further 204 adjustments for ignition timing.

Since our idle speed in 600-700RPM, the Unichip has the ability to adjust fuel mixture throughout the entire spectrum.

This is directly from the website.

How does Unichip increase engine power?
Every engine requires optimum ignition timing and air fuel ratio at all RPM and load conditions. unichip gives the experienced Dynamometer technician the access to and ability to adjust and optimize both the ignition and fuel system. Unichip has 17 RPM sites between 500 RPM and 8000 RPM and 12 load sites between zero throttle position and wide-open throttle position. This equates to 204 possible adjustments for fuel and a further 204 adjustments for ignition timing.

Since our idle speed in 600-700RPM, the Unichip has the ability to adjust fuel mixture throughout the entire spectrum.

Ok,but why would a tuner play with idle mixtures/timing etc when that can be left to the standard,well calibrated closed loop ecu program,it will give no gains anyways,I had one on my 1MZ-FE V6 camry and they didnt touch idle etc,they said its not needed nor recommended,bit like i said,if it was a fault of the MAF circuit,it would have to occur through the whole rev range load points would it not?,well that my take anyways,could be wrong

Cheers
Steve

My tuner said that the "tune" did not modify the idle settings, I understood it to mean that this circuitry was used in as a type of bypass mode for idling on Magnas. It definitely ran fine at revs above idle and ran roughly at idle. It is an inherent design flaw in the circuitry of the early Unichips. I think that the tuner also had some example failed units used on Falcons as well.

Ken N

I have personally never been a fan of piggyback units, simply because they dont control anything. They simply trick the ECU to think different things, in some states.