Outer Limits 4x4 Board

Howdy,
I have a Vitara 1.6 G16A EFI in my 89 Wt Sierra. It drives and runs great for about 40 minutes, then it feels like you have run out of petrol and it starts to miss or stutter, it gets worse untill it brings you to a stop. It still however idols perfectly at this stage, and can be revved a little, its most noticeable under load, especially on hills etc.
After switching off for 2-3minutes it returns to normal and can be driven again for another 10 or so minutes till the problem returns. I figure something is heating up and once switched off cools enough to go again, or when switched off for a minute or 2 something resets. Any Ideas??
Thanks Ian

had the same drama....fuel pump.

Yeah i was thinking possibly the fuel pump or possibly the Ignition module as these can bugger up with heat as well. But wasnt sure if the fuel pump suffered from heating up or how it kinda resets itself. It hasnt felt warm to touch.
Ian

one pump in tank or 2 external pumps?

Mr Emu wrote:Yeah i was thinking possibly the fuel pump or possibly the Ignition module as these can bugger up with heat as well. But wasnt sure if the fuel pump suffered from heating up or how it kinda resets itself. It hasnt felt warm to touch.
Ian

How can you feel the pump? It's in the tank ( unless as per Joe's comment you have an aftermarket external fuel system?)

Steve.

Sorry i should have mentioned. I run a 2 pump external setup. The first (closest to the tank) being a kinda standard square pump which makes a ticking noise, then the second being a cylindrical shape pump which kinda makes a wavering whirring electrical type noise i guess. They are not far from each other about 400mm and have a small filter inbetween. Then after the second pump there is what looks to be a regulator with a screw type adjustor.

So do you have 3 pumps in total? ie: internal lift pump then 2 external? Or is the first external pump gravity fed or something???

May I ask why?

You need a surge tank between the 2 pumps.

I'd guess the little facet pump ( the square one) can't flow enough fuel.

Or you could just fit a coil or vitara tank in the WT and use the in tank swimmer pump.

Steve.

Steve u don't need a surge tank in there using two pumps.

mine is setup like this.

carby Facet pump from tank and then a VL pump inline to engine with filters of course.

with only one pump i got surging and could not use full tank. can now run out of fuel with the two pumps

if your using a lift pump in the tank, than yes you might not need a surge tank, but as steve said if the pumps are external then yes, you should run a surge tank and have the fuel return feed in into it also. this fills the tank aswell as the low pressure pump.

nicbeer wrote:Steve u don't need a surge tank in there using two pumps.

mine is setup like this.

carby Facet pump from tank and then a VL pump inline to engine with filters of course.

with only one pump i got surging and could not use full tank. can now run out of fuel with the two pumps

You might get away with it, but there no guarantee you will - It depends too much on the flow rates/pressures of both pumps.

The only way to ensure you'll have no problems is to use a surge tank.

Steve.

I have no surge tank and only have the 2 pumps, no internal pump. I use an aftermarket long range tank. This setup has been running well for the past 5 years its just a new problem that has developed. Obviously one of the pumps may well be on the way out, just a matter of figuring out which one.
If i were to add a surge tank to the equation, how big should this tank be, just a litre or 2. Are there tanks available to buy?
Thanks Ian

For your size motor a 1.5 litres, even 1 litre probably would be fine. You can by generic off the shelf surge tank kits, most motorsport places should be able to point you in the right dirrection. Ebay and online stores, even places in teh states if postage is okay, shoudl be able to help you.

Quick search - http://search.ebay.com.au/search/search ... category0=


Or if you can TIG weld or know someone that can, then just make your own.

Layto....

Edit cause i fawked the link up

There's heaps available - some are cheap and nasty and awkward to mount, others are quite neat, rectangular with the pumps fairly integrated. they range in price between about $70 and lots and lots.

I don't like them at all in a 4WD, especially a sierra, but if you don't have a swirl pot in your stock tank it's the only way. I've done quite a dew EFI coversions and I've always used a vitara tank with with swimmer pump and integrated swirl pot.

With a surge tank, the big advantage is that the lift pump (the facet pump in your application) only has to move enough fuel for the engines consumption.

At the moment, you're moving the full fuel requirement of the EFI system with the facet pump.

Really, in it's simplest form, you need the fuel return to be between the 2 pumps, but that't what the surge tank allows. This will make your pumps happy.

Steve.

steve,
do you have pics of how your fitting up the vitara tanks in sierras??

Mr Emu wrote:Howdy,
I have a Vitara 1.6 G16A EFI in my 89 Wt Sierra. It drives and runs great for about 40 minutes, then it feels like you have run out of petrol and it starts to miss or stutter, it gets worse untill it brings you to a stop. It still however idols perfectly at this stage, and can be revved a little, its most noticeable under load, especially on hills etc.
After switching off for 2-3minutes it returns to normal and can be driven again for another 10 or so minutes till the problem returns. I figure something is heating up and once switched off cools enough to go again, or when switched off for a minute or 2 something resets. Any Ideas??
Thanks Ian

Back to the real problem, it sounds more likely to be the distributor getting hot, if it runs good for 40 mins or so you've used a fair bit of fuel in that time so would unlikely be fuel pump related,

Try fitting a different dizzy first - easier than a surge tank.

yes, the real problem, is its very likely to be a fuel pump. mine would only play up a couple of times a week (betwwen 200-400k's) and i run an in tank pump. sure enough....was the pump. if its running a standard vit coil etc they are very reliable, but check pumps first. also you should have a filter before the low pressure pump, not just one in-between.

nicbeer wrote:Steve u don't need a surge tank in there using two pumps.

mine is setup like this.

carby Facet pump from tank and then a VL pump inline to engine with filters of course.

with only one pump i got surging and could not use full tank. can now run out of fuel with the two pumps

i had this setup aswell, the lift pump needs to be the biggest 1 you can buy, i never had any problems with this set up, also what kind of filters are you running?, but it does sound like it could be a pump issue.

The filters i use are ryco and valvoline, the one between the pumps is just a standard sierra/vit one z367 or vf31. and then in the engine bay i use a commodore/falcon one being z200 or vf6, its a metal straight though kinda one. I have put new ones in since the problem started. A mate has a spare lift pump so i might try putting that in.

AND put in a filter BEFORE it.

joeblow wrote:AND put in a filter BEFORE it.

agree here.

i use a straight through carby clear one so u can see the rust/dirt.