GQ Nissan Patrol Diesel fuel consumption

i have got a 92 gq diesel non turbo and get same as you 420 to 450km to the tank.
have you checked air filters. i know you said its been serviced but sometimes these things get forgotten. cheers

You mention the injector pump but not the injectors..?? The injectors may not be atomising properley..? Did the change in economy come after you fitted the turbo.? If not then I doubt you have issues with the Turbo if it isn't that old. Has the air cleaner been replaced with a new one..? Were fuel filters replaced..??

Have your injectors checked.? Air Filter replaced.? Fuel filters..?? Turbo would last resort.

Just serviced 12 injectors on my boat (2 x Cummins Diesel Engines) as it was down on speed , putting too much black soot on the back of the boat etc, it doesn't take much , some of them weren't atomising properley and some needed replacement nozzles. The difference was amazing, got my top speed back, was down by 5 knots, expect fuel ecomony to improve also. In my Hilux I run Chemtech Diesel Injector cleaner every 3 or 4 tanks, I haven't had an issue although I strongly believe the quality of the diesel can change with different servos, I couldn't recommend a brand, not sure if it's all the same.

Good luck, let us know how it goes..

I had a 94 4.2 diesel GQ patrol with a Mike Vine after market turbo already fitted when I bought it. I was in the same boat the fuel economy was not all that great compared to a mates patrol. Just can't remember the k's per tank, but on asking around at the time I was none the wiser, had already done the injectors and the pump, so I looked up Mike Vine the guy who put the turbo in. I was lucky enough to have his shop near me so I took it back to him, he did things to it that were a bit over my head but $700 later it went like a rocket and was more economical. Sorry I can't be more specific but a guy who puts them in should know more than the local mechanic.
Wazza

GQ has a 95ltr tank, not 75...

this has occured only since fitting the snail the bleep economy?

Im wondering if you have at any stage lately used biodiesel ? The reason i ask is this, biodiesel cleans out sediment in your fuel tank and this is eventually pushed along the fuel lines and over a bit of time starts to restrict your fuel filter. Personally I would go back to basics first before spending huge amounts of money with expensive pumps and stuff.

From expierence (some wont agree with me here but thats ok) The injectors are good for 300,000 kms before thinking about having them changed. Most will tell you they should be done around 200,000kms but if you have looked after ur GQ as most long term owners do, then 300,000 is about right. Also makes a difference if you are using the factory std fuel filter as to an after market one.
Personally I would start with replacing your fuel filter...thats a good start and a cheap one.

NEXT... get rid of your pre filter, remove it and just use the oval one. Reason why i suggest that is from expierence. When i ran my pre filter, I went from 11 -12ltrs / 100 kms to 14 -16ltrs / 100 Kms. Turbos dont like them on, they need to breath heaps of air. The pre filter restricts air flow thus causing you to burn more fuel. Also If you have a donaldson fitted to your snorkel (assuming you have a snorkel) Take it off as well and fit the standard snorkel top back on. The Donaldson pre filter is not big enough for turbo diesels (4.2).

If after you try all that, things are still bad then start looking at injectors..its cheaper this way !

When i replaced my injectors on my GQ, it was worse on fuel for around 1000 - 2000kms, but then things started working for me and fuel economy improved.

Hope some of this helps you.
Ange.

hello there, take your jigger round to premier fuel injection at berrimah nt. they do good stuff , turbos, tuning, dyno, coffee, tall stories etc

I have a 90 GQ Td42 diesel naturally aspirated and no turbo. About a year ago with just over 200000k's on the clock it was getting fuel hungry and started smoking. Took it to a diesel specialist and they put it on the dyno. Found HP down and fitted new injectors, new air filter but removed pre-airfilter as it reduced the volume of air intake. Stated carry it but only use when in very dusty conditions. Didn't touch the pump as it tested OK. Got an immediate 15% improvement in economy. A few weeks ago she got sluggish on hills again. Took it to my local and he fitted new fuel filter and air filter - no pre filter- and it's a different vehicle again - literally flies (if a Td42 can be thought to fly).
Tow a 15' 6" van and get around 12.9L/100 on a good run and around 14.9 when there are heaps of hills to climb. She's no speedster but just plugs on faithfully.

Hi there,
There is a fine filter in the top of the fuel pump, if that gets clogged with crap your power and economy will go out the door. If you disconnect the banjo fitting off the intake line (top front left of pump) you will find the filter down in there. It is a fair way down and you will need a small pick to retrieve it. Some mechanics chuck it out when they service pumps because of the problems they present so it's possible yours is gone if it has been serviced! It's worth a look or a chat to the guy who did your pump 'cos they are a real pain if they block up!

Cheers...................Pete!

have you consided that its the way you drive i know that theirs no way i will get the conspution that my freind (member jamie mac) gets as he drives to the rev tacho on every gear every time the man could go in a fuel contest & win where i flog the crap out of mine & i get their sooner but alot more ltrs & we offen coment that he's is older with more Klms but mines done alot more engine revs making

I dont spose you have fitted a roof rack or mud tyres recently and the economy has changed since then???
Either of those things change economy quite a bit..

Hi.. Just wanted to let you all know that I had the Patrol looked at yesterday and had it Dyno Tuned. They went all over the engine and said it was solid.. They threw it on the dyno and noticed the boost was a little low (7psi) and the air fuel mix was very ordinary. They made some changes and upped the boost to 10psi and the trol has got its economy back as well as increased power. They suggested I should bring it in to get the injectors re-tipped but apart from that, shes all good again. Cheers for all the help guys and hope this info can be of use in the future to some of you. Thanks again.