4CU ECU...Re-solder.

[mrzigazaga]

Hi peeps...After reading an article on the inevitable failings of the ECU i have given it to a very good friend to re-solder, Even though I'm not having any issues ..YET!.. I didn't want to fudge it up so its best left to those who know what they are doing!...As you can see in the following pics there is some corrosion on the inner board and there was some contamination within the unit..It seems that it has been repaired properly at some point as there are new main components fitted.

The numbers have been removed from the chips which is a bit weird but then it might possibly be to stop anyone replacing them again...

Moisture ingress
1.

Corrosion on board
2.

Sand or rust?
3.

Dry joints
4.

5.

Minging connector pin
6.

Removed numbers?
7.

New heat sunk components.
8.

Thanks for looking...Ziga

[mrzigazaga]

Hi mate..Yeah it is hard to tell in the pics..But my friend is using a large magnifier so its easier for him to see..I have a receipt somewhere which says that the ECU was refurbed back in 2008 as part of an elimination process to cure a mis-fire that couldn't be traced..Its only happened to me a couple of times this year and TBH it hasn't re-appeared since a couple of cable ties were put around the unit holding the plug in place..Best to nip it in the bud as they say...It is a bit strange to see the numbers removed from the chips...Its not like they are specially designed...Cheers...Ziga

Edited by mrzigazaga on Sunday 19th October 12:20

[mrzigazaga]

Wedg1e said:

Hmmm, technically the ICs were specially designed: that was early days for large-scale IC architecture and Ferranti specialised in custom ICs (ask Clive Sinclair!).

Thanks Ian for the info...I meant to say that the chips weren't specially designed for TVR....Or were they?

Wedg1e said:

If the ICs have clear lacquer over them then the removal of markings was probably done at the factory; if you're looking directly at the chip's top surface then someone's done it since, probably to add an air of mystery

Very mysterious....But then i like mystery..

Well i have been informed its all done and dusted, And sealed to prevent any future moisture getting in..Should be able to collect it Monday or Tuesday...

Does anyone know why this resistor has been put there..I have been informed its not usually there?...Perhaps a mod of some description?...Cheers...Ziga


The workstation...(Come in No.5 your time is up.. )

Edited by mrzigazaga on Sunday 19th October 14:00

[mrzigazaga]

Wedg1e said:

The resistor is connected across pins 5 (earth, 0V, ground, as you prefer ) and pin 13, which is the input from the coolant tremperature sensor. So it's essentially the old frig to make the ECU believe the water's a different temperature than it really is.
By the look of it (allowing for monitor colour rendering) it's a '5-band' value of brown-black-black-red, or 100 and two 0s... 10KOhms.

So its a parasite then...Bugger....Would this of been done by Rover as i read something about it a while back...?
Cheers..Ziga

[mrzigazaga]

Thanks for the technical info....

Im now wondering if this attributed to my lean running and "Pinking" a while back with the solid state FPR?..Thats all stopped now i have an adjustable FPR...I did bring the psi up from 36 at WOT to 38, At the MOT the emissions were spot on.

Also if pin 28 is for an injector perhaps this was the cause of the mis-Fire, Maybe the two are linked, If the leaning off affected the injector with the faulty connection then that would make sense..I wonder if pin 28 is the left bank No.2 Cylinder as that was the plug i inspected..Sods law that on that day i only checked one plug...:roll eyes:

[mrzigazaga]

maston said:

Mr Fiddle would have done it for you mate

That just scares me........

maston said:

Didn't fancy having a go yourself then ?

Well TBH mate..There is a risk of doing more damage with the heat of soldering iron and i wouldn't have a clue what was dry or not so i left it up to someone who knows what they are doing..DIY is good but it can also stand for " Destroy It Yourself "...Give me some gunpowder and a match and i know where I'm at...

[mrzigazaga]

RCK974X said:

So if your wedge was running a bit rich, and especially when cold, this resistor would help - as per Adam's post.

Hi Andy..If anything mine was running lean when warm/Hot..Perhaps it was not working properly, I will hopefully see a difference when i fit it back on..Cheers...Ziga

[mrzigazaga]

After reading a fair amount as regards to the ECU it is mentioned quite frequently that it is the most unreliable part of the EFI system..Having it overhauled and new components fitted is beneficial, Gains in horsepower and fuel economy have been reported...Even tho its subsequently low its still an improvement.

Its amazing how simple in comparison to todays hard and software it is..Although it was i guess very "Hi-Tech" in its day...Don't you just love technology...

A Short story...By Ziga from planet Zog.

Upon one day, Maybe a thousand years from now..A meteorite will strike this Earth...A small percentage of the entirety of life will survive..10% of everything..Including flora and fauna..The dark ages will be upon MAN once again..Upon another day the light will come forth from the skies again...Some say the teacher of all things...Then the saviour will arise...In the shape of a Wedge...Its carcass gleaming in the atomic age...From the Earth it has been born..The silver GOD will be the door that unlocks the mind...The ECU will be the start of the destiny of mankind....fk I'm glad i won't be here...

[mrzigazaga]

Hi Peeps...Just a little update...Put the ECU back in and the car now starts after about 2 seconds..Idles really smoothly, Seems to have a better throttle response and actually feels a bit faster..Cheers Chris....Ziga