ECU stock vs special
ECU stock vs special
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carbon14

Original Poster:

57 posts

232 months

Saturday 1st September 2007
quotequote all
Hi I am trying to find out why my griff (94 preserp, 50K miles, recently bought) is weak of power above 4'500 (i.e. does not want to "push further" or go quickly "higher in the revs&quotwink. It sounds a little bit like a rev limitator and some light metallic noise emerges from the rear of the car.

All electric gremlins to the ECU have been checked - the thermistor wire in the loom was broken - now replaced (strangely there was no improvement after..)
All fuel line has been checked too, fuel pressure was too low, now fixed, and the valve before the inlet replaced as it was not operating correctly (no full opening).
All ignition has also been checked.
A glance in the engine through the oil "hole" shows a nice colour, no sign of bad things happening inside.
Engine is now running a notch better (but not above 4'500...)

Can anybody help tell me how to recognize if I have the original ECU, or if it has been replaced by a non-TVR or some unfortunate mods done ? I just had a look at it and it looks pretty new.

Thanks

AntonyJ

5,254 posts

311 months

Saturday 1st September 2007
quotequote all
The original ECU should say Lucas 14cux on it.

It is about 6inches square and black.

carbon14

Original Poster:

57 posts

232 months

Saturday 1st September 2007
quotequote all
Thanks it is such.
But I thought this description applies as well for the Rover stock motor as for TVR ECU (which is modified). Any way to see the difference for a TVR from a Rover one ?

spend

12,581 posts

281 months

Saturday 1st September 2007
quotequote all
Normally some 'TVR' hand writing on the label to say which engine it is destined for.

Dave

OscarT

758 posts

231 months

Saturday 1st September 2007
quotequote all
It sounds as if the ECU may be running on the wrong fuel map or limp home mode - have you tried resetting the ECU particularly after the repairs/amendments you have made.

carbon14

Original Poster:

57 posts

232 months

Saturday 1st September 2007
quotequote all
I found following handwriting on the sticker of the ECU "5.0c", sounds like TVR-like. Does anybody knows for what the "c" stands?

By resetting the ECU do you mean "plug out/plug in" the 24 pin wire set?
If yes, this has been done, after changing the broken wire of the thermistor, but not after the adjustement to the fuel pressure regulator. Shall I do it again?

The AJP Griff

4,360 posts

285 months

Saturday 1st September 2007
quotequote all
carbon14 said:
I found following handwriting on the sticker of the ECU "5.0c", sounds like TVR-like. Does anybody knows for what the "c" stands?
Probably means 5.0 litre 'cat',as opposed to a 5.0 'non cat chip which TVR also did.No harm in trying to re-set again i guess.

Bluebottle

3,498 posts

270 months

Saturday 1st September 2007
quotequote all
If it isn't electrickary, it could be a sign of cam wear. When my cam went the engine wouldn't push above 4.5k and as the cam got worse it developed quite a bad missfire at 4.5k.

carbon14

Original Poster:

57 posts

232 months

Saturday 1st September 2007
quotequote all
Bluebottle said:
If it isn't electrickary, it could be a sign of cam wear. When my cam went the engine wouldn't push above 4.5k and as the cam got worse it developed quite a bad missfire at 4.5k.
Thanks all.
Bluebottle it looks you have owned a similar same car I have (same production year, even the same colour ocean haze), sorry for you it ended badly. Your actual one looks terrific.
I wondered at which mileage did the cam wear happened, and how long did it last from the limitation to 4500 rpm until the missfire.
Did you had a spec cam?
I am asking because I got a TVR power confirmation from the records that my engine was delivering 306bhp at 5700rpm at factory and I wonder what did they fit in it to achieve such numbers without major engine mods.

Edited by carbon14 on Saturday 1st September 20:41

Bluebottle

3,498 posts

270 months

Saturday 1st September 2007
quotequote all
Those were good figures, It seems "some" of the HC badged engines did get a little extra work done to them by Power(bigger trumpets and some porting work but stock cam I have seen on a number, mine included).
The cam problem i had was with my current car (Serp), the missfire which started out more like pinking at high revs was the first sign of issues. I had the car serviced and it went away for a while then came back after a couple of weeks and rapidly worsend and it was at this point the car wouldn't rev above 4.5k (it was like hitting a rev limiter).
Hope your missfire doesn't turn out to be anything too serious, although 50k is about the average I am told for cam life in tivs.
Aparently my old Ocean Haze was repaired and re-registered a year or so after my insurers paid out. Every time I see an early Ocean Haze, I wonder if...scratchchin