Im currently experiencing a pain in the A*SE problem that has been narrowed down to a possible faulty ECU.
Im getting fuel cut in all gears and different speeds the problem occurs randomly with no pattern and is noticibly getting worse.
Ive been told that during a live data diagnosis im getting 'low voltage supply' to the idle control valve (certain thats correct) the cel flashes and dosen't stay on. Everytime the cel flashes 'ICV-low voltage' fault comes up each time after being erased from the ECU memory.
The ICV was changed and still the fault occured.

Has anybody got any idea if the low volt fault could be caused by a faulty ECU or for any other reason?

Zak at mocom had the car for the whole day pretty much and he said it was pointing towards the ECU.

Im not sure what 2 do next

 

https://www.scoobynet.com/general-te...lp-advice.html

 

Just read your reply and followed the link?
what are you saying? lol

 

Just read your reply and followed the link.
what are you saying or want 2 know? lol

 

1. State what car you have, including model year.

2. List modifications that may be relevant to your question or problem.

 

ah ok
Hawkeye JDM STI
Mods as per type 20 kit, sports cat, Miltek, K&N panel filter and remap

No further mods have been done since ive had the car which is approx 18 mths, all these were done by original owner.

 

low or high voltage doesnt alway smean that that paticular thing is faulty. it means that the message that sensor is getting sent is high or low so yo uhave to look further into things ie the source of the low voltage thats been sent. Idle air control valve usually brings up a no rpm signal error also

 

low or high voltage doesnt alway smean that that paticular thing is faulty. it means that the message that sensor is getting sent is high or low so you have to look further into things ie the source of the low voltage thats been sent. Idle air control valve usually brings up a no rpm signal error also

 

The only other complaint is a slightly blowing exhaust lol

This may have nothing to do with it and may be a load of gibberish but it happens almost all of the time if i go over a speed bump whilst holding the revs at say 3k, the second it 'bumps' over, FUEL CUT and kangarooing for want of a better description lol
Its hard to explain lol and may not have any relevance to the problem, Its just strange that it does it, its making me think something could be loose etc?

BUT then again Zak at mocom checked the car over and said all else seemed fine?

 

Sounds silly but is your K&N installed properly ? nipples off and a good seal on the intake/box etc ? Under boost in all gears could mean your getting a shed load of unwanted unaccounted air on boost ?

 

Voltage out of the ECU ICV terminal is lower than should be, Zak followed a proceedure (not sure exactly what) after doing what he did should see the voltage increase to what i believe should be approx 5v but continued to stay low, 1v i think? either way he said it was low

 

He said all figures during live data were spot on and the 'fault' occured at different revs and boost, totally random and the only prob he could see was the ICV low volt fault.

 

Who mapped the car? I would think any good mapper woudl nail this almost straight away after looking at the data log?

 

dont you just hate these issues, maybe change the icv

 

The mapping was done by powerstation.
Surely mocom would have mentioned this as he maps cars himself?

 

Ive forgotten what the car feels like to drive 'normal'
We changed the ICV still the same.
what 2 do next?

 

 

 

I can't see how a good mapper & garage 'Powerstation' cannot diagnose the problem when they had it all day, or has he diagnosed it already?

If he suspects the ECU and car has been there all day, I would be considering buying another ECU. I dont think its a case of plug'n'play as you may need to sort out your Immob. Have you suggested to him that you want the car fixing and returning when done? To fit another ECU is simple, but to configure it to run is what he can do surely.

Rob

 

It's trying to source the correct ecu thats the problem, plus he only needs to test it so it can be eliminated from the list of probable faults

 

ideally id like to find someone on here with 1 and try it it my car so I can literally eliminate the ECU as being the problem, if it is the ECU then ill have to hunt 1 down replace and then remap it, id guess?
Just want my car back to normal

 

How far away from Powerstation do you live Subeyman?
If PowerStations map is still loaded in the ECU then they will have access/ability to modify it during diagnosis.
Might be easier to track down the actual fault before forking out on a new ECU
(they rarely go wrong)

 

I think you misread something there Prodrive, it appears from what I can see, PS mapped it for the previous owner over 18 months ago.
It's Mocom that's doing the current diagnosis.