No power under load while on petrol

Runs fine on gas.

Petrol it's like it's starving for fuel under load. This problem has always been there, but seems to be getting worse. I have changed the fuel filter and have pulled out the vacuum hose off the fuel regulator and that was dry. I don't think it's injectors as I ran a screwdriver over them and can hear them clicking, I disconnected all of them but the last 2 one at a time and there was a noticeable difference which there should be. no black smoke at all. I know that these tests are only basic, but that's pretty much all I can do at home.

Starts and idles fine. Fuel pressure should be the same at idle and while under load, yes.

Fuel pump is in the tank? How would I go about checking it's working correctly and what else can I check..

Thanks all.

How often do you run the petrol side of things??

Every time it starts. Runs about a K or 2 then it switches over to gas. Gave it a run up the hills towards Bacchus Marsh with 30 litres of fuel and 2 bottles of injector cleaner about a month ago didn't make much of a difference.

Quote:

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Originally Posted by jay see

Runs fine on gas.

Petrol it's like it's starving for fuel under load. This problem has always been there, but seems to be getting worse. I have changed the fuel filter and have pulled out the vacuum hose off the fuel regulator and that was dry. I don't think it's injectors as I ran a screwdriver over them and can hear them clicking, I disconnected all of them but the last 2 one at a time and there was a noticeable difference which there should be. no black smoke at all. I know that these tests are only basic, but that's pretty much all I can do at home.

Starts and idles fine. Fuel pressure should be the same at idle and while under load, yes.

Fuel pump is in the tank? How would I go about checking it's working correctly and what else can I check..

Thanks all.

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@jay see

Disconnect your Battery for 45 minutes and whilst you about it clean your MAF sensor.

Disconnecting the Battery erases learnt codes in the I/C.

Mine does the same if I run on Gas for extended periods.
Mine also always starts on Petrol and switches to Gas

Bet my Family Jewels that this will fixit LMAO

Quote:

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Originally Posted by Bob

@jay see

Disconnect your Battery for 45 minutes and whilst you about it clean your MAF sensor.

Disconnecting the Battery erases learnt codes in the I/C.

Mine does the same if I run on Gas for extended periods.
Mine also always starts on Petrol and switches to Gas

Bet my Family Jewels that this will fixit LMAO

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Thanks for that Bob.

I did all that at the last service..

Will give it another go now and see what happens.

If it doesn't work you can keep the family jewels mate. Lamo..

Have taken it out to clean and noticed that the top wire isn't straight like the bottom one. Is this how its meant to be?

http://www.nissanpatrol.com.au/forum...2017/03/79.jpg

Went out to pick up my son and it's better not good, but driveable now. I've cleaned that maf sensor a few times and have never had a result as good as this before. Will test the voltage next.

At least now you have a starting point,OOI has your timing moved.
should be just off pinging when on petrol, thats where my dual fuel 4x4 ran best
then again it never had Maf or any sensors that I could mention

Tried doing it like this.

TB45
There should be a Black/Red wire, Black and White wire Term 2,3 &4
With the car idling, warmed up in nuetral and ac off there should be the following
The 3 (B) should be reading 0v
The 4 (W) should be reading 1.3 to 1.8v, and with the engine at 2500rpm should be 2.1 to 2.5v
With the car of disconnect the MAF plug turn the ignition on and test
The 2 (B/R) should be reading the battery voltage.

Got the last ones done 12.4v, but that's as far as I got. The pins on my mulitmeter broke off so unable to get through to the wires while it's plugged in..

Quote:

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Originally Posted by jay see

The pins on my mulitmeter broke off .

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How did you manage that? Were you getting cranky of having to do all the diagnostic work? ;)

You will get to the bottom of it by a combination of elimination & direct testing.

Do you have a vacuum/fuel pressure meter? Checking the fuel pressure might be a good idea.
Just make sure it's not running too lean due to fuel starvation.
Chances are it's an electrical issue whether it's a fuel starvation issue or something else.

Just a little more info on the TB45E ECU data. Disconnecting the battery will only erase the STFTs (short term fuel trims). These are very quickly relearned by the ECU.
Erasing the LTFTs (long term fuel trims) requires a Nissan Consult device or can be done with an Ecutalk cable and ODB Scantech software on your laptop.

Long term fuel trims are learned over a longer period (hence why the factory didn't allow erasing every time you disconnect the battery for some unrelated reason) and are not easily influenced by a sudden problem unless it's allowed to persist for a while.

you can plug in my ECU-talk if you want and delete any errors ??

Quote:

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Originally Posted by threedogs

you can plug in my ECU-talk if you want and delete any errors ??

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Thanks John.

Yours won't suit my plug.

Found this last night.

http://www.nissanpatrol.com.au/forum...2017/03/84.jpg

Didn't know that there's one to suit.

Might have to invest in one.


Can any please confirm that my maf sensor is alright, does the wire not being straight affect it's operation?

Im pretty sure as long as its connected either side and not snapped it should be fine.

May need to check out the 02 sensors. Check the timing too

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@Roofy suits Bobs
that one you showed is the same as mine,
cant see why it wouldnt suit

Quote:

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Originally Posted by Mike02Ti

Im pretty sure as long as its connected either side and not snapped it should be fine.

May need to check out the 02 sensors. Check the timing too

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That's my thinking too. I think I'm just trying to pinpoint something that's wrong.

Wouldn't 02 sensors throw up a engine light?
Timing was done a few weeks back.

Quote:

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Originally Posted by threedogs

@Roofy suits Bobs
that one you showed is the same as mine,
cant see why it wouldnt suit

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Different plug connection. My is consult port yours would be obd.

Not necessarily. If the 02 sensors functioning somewhat they may not throw a code.
Mine on my 48 are buggered. Using about 30l/100km.
No code or engine light but all over the place when i read them with NDS II. Runs great on gas though.
Also check the cat converter and see if its blocked


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@jay see

I have ECU talk and OBD Scantech loaded on a Laptop together with Connecting Cable to OBD Port.

You are quite welcome to use

I have a 1998 4.5 Litre Patrol so it should be compatible with yours.

I live in Pakenham

Regards
Bob

Quote:

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Originally Posted by Bob

@jay see

I have ECU talk and OBD Scantech loaded on a Laptop together with Connecting Cable to OBD Port.

You are quite welcome to use

I have a 1998 4.5 Litre Patrol so it should be compatible with yours.

I live in Pakenham

Regards
Bob

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Thanks Bob, is yours a consult port grey 14 pin?

Quote:

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Originally Posted by jay see

Thanks Bob, is yours a consult port grey 14 pin?

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Yes it is

@jay see

Quote:

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Originally Posted by Mike02Ti

Not necessarily. If the 02 sensors functioning somewhat they may not throw a code.
Mine on my 48 are buggered. Using about 30l/100km.
No code or engine light but all over the place when i read them with NDS II. Runs great on gas though.
Also check the cat converter and see if its blocked


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Was speaking to a mechanic the other day. And he said that the MAF sensor has nothing to do with the engine while running on gas wonder if the O2 sensors are the same. Exhaust is as old as the car so may have a good chance that the catalytic converter is blocked but wouldn't that also affect the performance while running on gas.

Quote:

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Originally Posted by Bob

Yes it is
@jay see

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OK and your using the same unit that I posted the pic of?

Might need to find some time to travel up your way.

I know my gas system takes no readings from the factory o2 sensors. It has its own sensor welded in and wired to the gas control unit sitting in my engine bay.
And he is right about the MAF sensor too.
Yeah you would probably see a performance drop on gas too if the cat was stuffed. How much i dont know. Especially if you are used to it over time.

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Quote:

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Originally Posted by jay see

OK and your using the same unit that I posted the pic of?

Might need to find some time to travel up your way.

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Yes except the display is on the Laptop and not the Rectangle one shown
http://www.ecutalk.com/ecutalk.aspx

@jay see

OOI what shape is your dianostic port under the steering wheel

Quote:

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Originally Posted by threedogs

OOI what shape is your dianostic port under the steering wheel

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see attached

http://pinoutguide.com/CarElectronic...e_pinout.shtml

Quote:

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Originally Posted by Bob

see attached

http://pinoutguide.com/CarElectronic...e_pinout.shtml

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Same.

http://www.nissanpatrol.com.au/forum...2017/03/88.jpg
@Mike02Ti
I had a look at the 02 sensor and it has two wires coming out of the plug, one goes to the gas system. Looks like it a similar set up as yours. I think I might be able to get my hands on a scan tool of some sort, just need to find out if it will connect to my plug.

Edit
No good with the scan tool. Only does odb2

@jay see if you download NDS I for android or for windows you will be able to check out codes etc you should also be able to check out the readings from the o2 sensor as well. I have been using ndsII for a while for checking stuff and it's great to use. The android app will only read ECU . The windows version reads ECU and TCM
Only thing you will need is a consult I plug either usb for windows or bluetooth for android.
Maybe a member around you has one to borrow?
Alternatively you can get an adapter from consult to obdii style as well


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I did try a while ago with a Bluetooth obd2 and adapter cable. Worked well on my wifes ve, but did nothing on the patrol.
Will need to look at it again.

Something like this.

Look at this on eBay http://www.ebay.com.au/itm/272583885496

Never mind.
I've had a look at the nds site. 👍

OK I think I'm going to go with this.

http://www.obdinnovations.com/nissan...stic-interface

And the NDS1 for Android.

Can't find the Bluetooth plug locally, this one is from the US.
Mike where did you get yours from?

My bluetooth plug is the OBDII ELM327 type from jaycar. Works well.
Sucks you cant get one local for consult.

But i have an advantage of mine having the OBDII port from factory and not the consult plug like yours.

Im just wondering though if you could convert the consult plug to an obd style...... might need to check out the pinouts and see. I dont see any reason why this couldnt be achieved as basically thats what a consult to OBD adapter is.

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@jay see i just checked out the service manual. Under the first revision 1997
EC28 goes through a diagnostic test mode for the oxygen sensor

Not too far above these pages talks about the whole fuel and ignition system going into open loop when something is up with the MAF , injectors , o2 sensor.
What i gather from reading this is then the ECU will try to calculate its own values to keep the car going as best as it can.

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Quote:

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Originally Posted by Mike02Ti

My bluetooth plug is the OBDII ELM327 type from jaycar. Works well.
Sucks you cant get one local for consult.

But i have an advantage of mine having the OBDII port from factory and not the consult plug like yours.

Im just wondering though if you could convert the consult plug to an obd style...... might need to check out the pinouts and see. I dont see any reason why this couldnt be achieved as basically thats what a consult to OBD adapter is.

Sent from my SM-G920I using Tapatalk

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Oops I forgot about that.
I've tried something like this with a obd2 elm327 and it didn't work. Something about protocol.

http://www.nissanpatrol.com.au/forum...2017/03/95.jpg

Probably why people go with the PC/usb version.

Quote:

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Originally Posted by Mike02Ti

@jay see i just checked out the service manual. Under the first revision 1997
EC28 goes through a diagnostic test mode for the oxygen sensor

Not too far above these pages talks about the whole fuel and ignition system going into open loop when something is up with the MAF , injectors , o2 sensor.
What i gather from reading this is then the ECU will try to calculate its own values to keep the car going as best as it can.

Sent from my SM-G920I using Tapatalk

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Will have a look at it. Thanks.

Driven about 150km on petrol the last few days. Doesn't feel like its starving for fuel anymore, but does feel like it's down on power a little.

Think I'm on the right track looking at sensors. Still got me stumped why the battery disconnect and maf clean worked so well this time, have done that a couple of times in the past with no difference.

Thanks for all the help/info guys much appreciated..