Tornado chip

[Mr Pig]

I had a Tornado chip fitted today by an extremely knowledgeable specialist garage just to see if I could improve the way my 4.0HC ran at the bottom end. After all even without a full re-map it should be a vast improvement on the original TVR chip.
Everything was checked, including emissions, all ok. New chip fitted, car fired up and it ran like a sack of sh@te and the MIL light came on. Emissions all wrong as well.
Original chip replaced everything fine. So what causes the MIL light to come on? Please help!

[derbygreg]

I was thinking about doing that with my HC... Sick of driving at 2K RPM only...

[Griffter]

[redacted]

[chassis 33]

The MIL gets switched on by the ECU when the ECU detects there is something amiss with itself, it may be that the chip hasn't quite been fitted properly, pushed home properly that sort of thing or that the chip itself is in somewhat faulty. It's not unknown for information to get corrupted as its transferred onto the chip, however I would of hoped there would be some sort of checking process before the chip was sent out.

Regards
Iain

[ntel]

Mr Pig said:

After all even without a full re-map it should be a vast improvement on the original TVR chip.

Obviously not.

[FunkyGibbon]

drop PHer Mark Adams an email - he should be able to help.

[Cider Andy]

Mr Pig said:

After all even without a full re-map it should be a vast improvement on the original TVR chip.

Fitting the Tornado chip IS a full remap. Whilst there should be a marked difference in how the engine behaves, I wouldn't necessarily expect a 'vast improvement'.

Didn't it come with a 'scrambler'? On the basis that the fault disappeared once the original chip was refitted, then either the chip or the scrambler is faulty, or the data on the chip is corrupt, as Chassis33 said. It's also worth checking the tune resistor is correct for the set-up and whether or not it has been disturbed.

[blitzracing]

A frequent test any computer based ECU will do is a checksum test on the Eprom you have fitted. Basically it takes all the ones and noughts the digital fuel map comprises of and works out a figure for what the total value should be. It then stores this with the fuel map data, so when the ECU initialises it checks every location value against this "checksum". If the two dont tally then an error is generated indicating the Eprom data is not valid. It seems very unlikley that anything else could cause the ECU to error in this case, unless the Tornado map has some tighter external sensor values, and one is out of tolerance.

Have a look
www.pistonheads.com/gassing/topic.asp?t=196780&f=8&h=0

[fergusg]

My 95 4.0HC runs very smothly. I can tootly along at 30mph in fifth at just over tickover without any shunting. I generally don't as I'm not sure running this slow does the engine much good. The reason I am posting this is perhaps there is something else wrong other than the chip if you're car isn't fairly smoooth.

[targarama]

You need to get the chip tuned to your car. My Chimaera had one, I bought it, stuck it in and it didn't make much difference. However, after a custom remap by Mark Adams the car was much smoother and more powerful.

[Mr Pig]

Griffter said:

Without meaning to sound as sarcastic as I inevitably will, just how knowledgable are they then?!

Check: throttle pot settings, afm CO trim, ignition timing.

Emissions at idle won't tell you mnuch - you need to get the car on a rolling road.

Thanks everyone for your thoughts. Everything was checked by the specialists and found to be correct so there must have been a fault with the chip. I am awaiting the feedback from that from the supplier. I know the only way to do this properly is to have the chip mapped to the car but funds only allow this to be done in two stages. I will keep you posted.