day is getting worse, ecu burnt inside

[Latty666]

just unscrewed the cover of the ecu and the chip in the bottom right corner (16 pin)is toasted, all black and smells of burning, worrying though the car still runs, can anyone shed any light on this?

[QuiteQuietCerb]

theres an ecu for sale on ebay at the moment, check your big fuse

[purpleliability]

I'm sorry to hear that mate,I have an ecu available if you just want to replace it,pm me,it will be a good price

[Tanguero]

http://www.pistonheads.com/gassing/topic.asp?t=117...

And don't worry about the big fuse - that is only between the battery and alternator so nothing to do with it.

[matty1275]

not sure but that might be the memory chip, they are about £50 if i remember rightly

I had a problem with my ecu, sent it off to the chaps who are mbe's agents and they did a full refurb and soak test for a really reasonable price

[Latty666]

Purpleliability email me my email is [e-mail] . Id pm you but I'm on mobile site and it won't allow pm, as for the ecu , iv plugged it in and it is connecting to the diagnostic software but the adaptive maps don't make sence , which may explain it being the memory chip, the car was running something like but now it is just misfiring and popping and farting, guessing something else is damaged either with the ecu or the coils.

[crypto]

Latty666 said:

Purpleliability email me my email is [e-mail] . Id pm you but I'm on mobile site and it won't allow pm, as for the ecu , iv plugged it in and it is connecting to the diagnostic software but the adaptive maps don't make sence , which may explain it being the memory chip, the car was running something like but now it is just misfiring and popping and farting, guessing something else is damaged either with the ecu or the coils.

I'd say it's almost 100% NOT the memory chip. If the memory chip is bad your ECU wouldn't do anything and the engine wouldn't start either. Within the ECU there are some ingnition coil and injector driver chips which may go bad. Can you put a pic of the ECU in ?

Did this happen all of sudden or is there anything particular you have done (taking things apart, cleaning ;-) , etc. ?)

[Latty666]

I replaced the ecu today , I still have a misfire although the damage to the original ecu looks/ smells like it's been like it a while, I have changed the rocker covers and removed a manifold to be welded before the misfire occurred , I have checked all the connections to ecu, including the 1 under the coolant header tank, the leads are seated ok, plugs are recent , the throttle pots are set , I'm scratching my head a bit with this, I'd guess at coils but for both to go at the same time would be a bit unfortunate

[crypto]

Latty666 said:

I replaced the ecu today , I still have a misfire although the damage to the original ecu looks/ smells like it's been like it a while, I have changed the rocker covers and removed a manifold to be welded before the misfire occurred , I have checked all the connections to ecu, including the 1 under the coolant header tank, the leads are seated ok, plugs are recent , the throttle pots are set , I'm scratching my head a bit with this, I'd guess at coils but for both to go at the same time would be a bit unfortunate

What do you mean with "checked" ? Visually inspected or really measured with a multimeter ?
If you have misfire, are the cylinders (not) firing just randomly or is it only 1 or 2 cylinders not firing correctly ? Sometimes this may help finding the non firing cylinder(s) :

http://www.ebay.co.uk/itm/Digital-Infrared-IR-Ther...

Just point it to exhaust manifold (of each cylinder) and temperature should be equal within 20 degrees

[Latty666]

Visually checked all terminals , cleaned with contact cleaner , as for the ir tester I also have had that pointing at the manifolds , all cylinders are near enough the same temp , the misfire is irratic , all over the engine not just on 1 or 2 cylinders... Cannot see 2 coilpacks failing at once, or 2 lambda's , I'm starting to question injectors or fuel pressure?

[Nickccc]

I don't know if you have removed the lambda's but if you have, they aren't plugged in the wrong way round are they.
When you look at the adaptive maps are you seeing numbers logging to both banks?

[crypto]

I would verify the electrics with a multimeter. With the help of a second person measure the resistance from the pin in the ecu-connector until the end of the cable going to all sensors, injectors, lambdas, coil-packs, ...

If you know the resistance of the components, you don't even need to disconnect them. E.g. the lambdas should have about 6 Ohms (measured to ground).
I particularly found this file helpful (sheet 1 shows the wiring and sheet 3 the connector pinout).
http://www.thetvrsite.com/files/wiring-diagrams/AJ...

Disconnect the main battery before measuring, if all is ok, reconnect the (fully charged !) battery and check supply voltage to the coil-packs and injectors (and its fuses ?).

Is the label on the EPROM memory in your new ECU the same as in the burnt old one ? If the misfire is random, it would be logic that it is a central component ? (e.g. crank sensor, coil-packs & injectors supply ?)

[Latty666]

The EPROM is the same as old ecu, the voltage at the coilpacks when tested has changed from 3.9v to 8v, yet at the 19pin it's 12v , iv checked the connector under the coolant tank yet I don't have the pin out for that socket

[crypto]

pin 3+4 of the coil-packs must have 12 volts, pin 1+2 will be pulled to GND by the ECU when Engine is running. if ignition is on (but engine not running), pin 1+2 should have 12v too, you should not have floating voltages on these pins.

check the cable-loom resistance with an Ohm-Meter from pin 1 coil-pack(s) to pin 19 & 40 of the ECU as well as pin 2 to 20 & 55 of the ecu. the value should be less than 1 Ohm.

on what pins did you mesure 3.9 to 8 volts ? a drop of 4 volts in cable seems a lot, somthing must get warm !

[Latty666]

Pin 3+4 have the varying voltage, on both coils too, Pin 1 acts as a gnd , pin 2 seems pretty lifeless with just the ignition on , I need to open up the loom and trace the wiring back in to the car as Its difficult to see what goes where as it is