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Bob
23rd November 2014, 09:47 AM
I have a 98 Dual Fuel 4.5L which has a problem that I am having trouble getting sorted out.
If I run on say Gas for 400/500 K when I switch to Petrol it runs really rough. The same if I run on Petrol
Easy fix just disconnect the Battery for say 15 minutes and all is well.
I would like to disconnect the ECU only without having to reset all my Radio Stations , time etc.
Can someone advise me where the Power to the ECU is located.

This is only a temporary fix as the Wiring for the Gas will be reinstalled when I can afford it.(It is a bloody Snakes Nest)

Yendor
23rd November 2014, 12:04 PM
Disconnecting fuse 49. It's 7.5amp fuse in fuse box under the bonnet. Should reset the ECU.

04OFF
23rd November 2014, 02:45 PM
I was under the impression the ECU had a internal battery/capacitor Rodney, and after discharging residual current, you still the need to leave it sit (battery disconnected) for up to 3 days to totally clear the memory ?

Or know someone with a scanner that can clear the memory instantly.

threedogs
23rd November 2014, 02:59 PM
You mean like a ECU-TALK ?

04OFF
23rd November 2014, 03:05 PM
Maybe, I think you might be able to do it with a ECU talk but ive honestly never used one, regardless id really like to get one for my TB45 anyway just to monitor stuff etc.

Yendor
23rd November 2014, 03:12 PM
Bob's not trying to clear codes. He's just trying to reset the fuel trim when he changes from one type of fuel to the other.

04OFF
23rd November 2014, 03:17 PM
I.C. so anyway, say if I fit a new o2 sensor for instance, is it true you need to wait a few days to really clear the memory (or use scanner) ?

Bob
23rd November 2014, 03:17 PM
Bob's not trying to clear codes. He's just trying to reset the fuel trim when he changes from one type of fuel to the other.
Yes that is right.
Disconnecting the Battery for 15 minutes does the job
I just want to be able to do it without having to reset the Radio Stations & Time

04OFF
23rd November 2014, 03:18 PM
And why is your location greenbank, did you give the forest the arse ?

Bob
23rd November 2014, 03:19 PM
Maybe, I think you might be able to do it with a ECU talk but ive honestly never used one, regardless id really like to get one for my TB45 anyway just to monitor stuff etc.
I have a Nissan Consult but have never used it .
Must get off my Arse and set it up

04OFF
23rd November 2014, 03:31 PM
Or give it to me and ill test it out for you for a few years at no charge , can't promise youl get it back, but for the service you will receive for free I think its well worth it :bigthumbup: (lol)

threedogs
23rd November 2014, 03:43 PM
cant you use those 9v battery connector that plugs into your lighter to save memory

Yendor
23rd November 2014, 05:07 PM
I.C. so anyway, say if I fit a new o2 sensor for instance, is it true you need to wait a few days to really clear the memory (or use scanner) ?

Disconnecting the battery or hopefully fuse 49 for 15 minutes will do.

Unless the old o2 sensor had set a code that you were trying to clear.

Yendor
23rd November 2014, 05:08 PM
Yes that is right.
Disconnecting the Battery for 15 minutes does the job
I just want to be able to do it without having to reset the Radio Stations & Time

Fuse 49 is the memory to the ECU so it should to the trick.

Yendor
23rd November 2014, 05:09 PM
And why is your location greenbank, did you give the forest the arse ?

Yep moved on to bigger and better. I've spend the last 6 months repairing the old house, moving and then setting up the new house. I'm so over it..... LOL

04OFF
23rd November 2014, 07:38 PM
So whens the house warming party (that's all I really care about, lol)

jff45
23rd November 2014, 08:50 PM
I don't think 15 minutes disconnected would be enough to clear the long term fuel trims i.e what Nissan call the AF Alpha self learn.
Ecutalk can do it easily using the OBD Scantech software supplied with it.

Bob
24th November 2014, 07:35 AM
I don't think 15 minutes disconnected would be enough to clear the long term fuel trims i.e what Nissan call the AF Alpha self learn.
Ecutalk can do it easily using the OBD Scantech software supplied with it.

I am not expert enough to dispute this however disconnecting the Battery for 15 minutes always fixes my problem.

04OFF
24th November 2014, 08:58 AM
I am not expert enough to dispute this however disconnecting the Battery for 15 minutes always fixes my problem.

Wish all problems were that easy to fix Bob (lol)

Bob
24th November 2014, 02:36 PM
Wish all problems were that easy to fix Bob (lol)

Sorry you miss out on the Nissan Consult & ECU Talk as I have just installed it so will have to start learning how to use it.
So far cant see how to clear long term Fuel Trims

threedogs
24th November 2014, 03:08 PM
Peter at ECU-Talk is great if you need any info

jff45
24th November 2014, 03:23 PM
Sorry you miss out on the Nissan Consult & ECU Talk as I have just installed it so will have to start learning how to use it.
So far cant see how to clear long term Fuel Trims

The Ecutalk display doesn't reset the LTFTs. You simply use the USB cable through the Ecutalk to access the ECU using the supplied OBD Scantech software. You can also check your auto trans with it.

Bob
24th November 2014, 04:02 PM
The Ecutalk display doesn't reset the LTFTs. You simply use the USB cable through the Ecutalk to access the ECU using the supplied OBD Scantech software. You can also check your auto trans with it.
I don't appear to have had OBD Scantech software supplied when I download ECU Talk.
Will investigate

jff45
24th November 2014, 04:30 PM
I don't appear to have had OBD Scantech software supplied when I download ECU Talk.
Will investigate

Peter usually supplies it on a small CD with the Ecutalk software. Did you buy the LCD display or only the cable?

Bob
25th November 2014, 03:40 PM
Just a Update

Have installed ECUTALK and also OBD Scantech.
With OBD Scantech I have managed to clear Learned Codes which means I now don't have to disconnect the Battery.

Thanks to Peter at ECUTALK and also jff45