The never ending guzzler

[cors]

HELP
Seriously shocking gas economy going on in my van.
Vehicle gross mass, kg
— with engine =2800kg

Displacement =2.285L
Compression ratio = 9.3
Rated power, net, =72.2kw (98hp)
Max. torque, net =17.2daNm (17.5kgf.m)
— at the engine speed, rpm 3500rpm

regarding my gas usage , atm on 4.5km/1Lt or 22lt/100km

Petrol usage was around 15lt/100 and i thought that was shocking so i re-jetted the carby with smaller primary jets last time i was in town.Have not really run it on petrol for a while.

When i bought the car the guy said he was getting 250-280km for a tank , which i thought was preety bad aswell considering i had just come from AUS and the van i was using was duel fuel doing about 400km/55lt,depending on how much highway cruzzing i did.

This car gives me a sad face. Next month i leave again and i wont be back for 4 months.
We live in a building complex here and the car had been scraped along the edge at night (well every car does) if your the unlucky ones to find on street parking.
I literally cannot picture myself buying a nicer car if i live in this complex and the van comes in handy all the time.
Ive done vacuum tests , compression tests(everything seems average for a motor).
I almost live with the DIY sensor in the exhaust , i can run it with the probe showing .05 the whole tank, i can run it with no uphill load power at all and i have to change down gears, i can drive it under 2500rpm for the whole tank.
When i pull over on the street my wife knows i am going under the hood for a fiddle.

There one thing i am going to do and that is drill a hole around the resonator and fit the lambda probe there.

[cors]

I spent weeks on a russian gaz forum trying to evaluate what the cars stock Ltr/km was and i dont think anyone truly knew,people said about 12-14 for that motor size, maybe 14lt/100 for a gazelle/sobol.

[Gilbertd]

You could return it to it's original state. As it's a Russian built version of the old style Ford Transit (with a funny smiley radiator grille), you could always bung a 2 litre Ford Pinto lump in it like the original design had. Plenty of people know about them.........

Thinking about it, you could always post up a picture of it for the benefit of those that have not ventured that far East and seen one. At least then everyone else would know what we are talking about (and they could all have a laugh at that odd looking radiator grille too!).

[cors]

I will get some pics up soon.

[cors]

hello, i have been busy, I really want to succeed in this install and tune out all the unknown variables.I like LPG, its become a bit of a hobby for me.
I Have fitted new GAs filter lock off & petrol Lock off,
I also bit the bullet , pulled out the drill and fitter the Lambda zont in the pipe(located between resonator and main muffler).
Didnt have a welder and could not be bothered trying to explain to a local why i wanted a Nut welded on the exhaust, so i figured another way.

[cors]

Im trying to modify 2 mixers into 1 usable mixer. I am taking an EFI inline mixer and trying to fit it to the old mixers carby shroud.It can work, but the biggest problem is the air filter box has a silly hollow in the middle.As you can see by the above pic(stupid design the hollow fills up with water and i get to boil some eggs on the way to work.
I have not sourced another filter and am reluctant to go down the tubes/pod filter route.
I am thinking of cutting the center out and installing it upside down with the lump facing up.this would solve all my problems and cost nothing but pop rivets and gasket maker, but i have not done it yet.

Atm i am getting a faster read out of my DIY tester compared to throttle movement(really glad i moved it now)
Pilot screw is all the way in.
I have a lean reading at idle which the motor likes, but off idle is a little lean(due to poor mixer design).Normal driving though does not show lean at off idle.Average reading is about .85, throttle hits see a .9-.95 reading.
It still smells of gas at idle(unsure about driven though).
I changed back from LPG plugs to an iridium Normal plug type aswell.
I am wondering why the exhaust smells of gas and shows a lean reading at the same time.
I need to do a test and garantee spark to all cylinders.

[rossko]

I am wondering why the exhaust smells of gas and shows a lean reading at the same time.

Understand what the oxygen sensor does ... it senses oxygen in the exhaust. It tells you nothing about the fuelling directly, though we (and electronic controls) use it to draw inferences.

If you detect more oxygen, you may well interpret that us meaning "lean". But it might not be ; if we have a cylinder with incomplete combustion - maybe wonky spark, poor compression, blah - it will let unburnt oxygen into the exhaust for the sensor to detect, as well as unburnt fuel for the nose to detect. It tells you nowt about the air/fuel ratio in the poorly cylinder(s) and masks the air/fuel ratio in any 'good' cylinders.
You can in fact wind up the mixture on an engine so far that richness causes misfire ; the oxygen sensor duly reports oxygen which can be completely misinterpretated as "lean".

[cors]

Ive done some more stuff.
Firstly i checked the spark. ouch .... seriously though all cylinders drop a lot of revs when the spark plug boot was removed.Spark could even be heard coming from the boot and arcing on the Rocker cover sleeve.All revs dropped consistently.

I seem to have a problem setting the power valve, can a situation arise whereby the power valve if screwed in enough affects idle gas draw which requires me to turn out the bias screw to compensate, but the overall gas draw @3000rpm is still reading excess rich!
Did i explain this situation clearly? or am i missing something?Can this situation happen at all?
What gas pipe mods can i make to alleviate this situation?

regards

[cors]

I added some small pipes in the hope to create extra gas draw to the primary venturi.
Not sure if it will do anything.
I need to replace the red gasket maker stuff with something that will last too.

[cors]

Did some further exploration on the electrics and found one of the spark plug boots was faulty.According to the ohms meter test it did not have any value whereas the other 3 had 5.60 ohms value.Replaced and instant gas smell gone.
Unfortunately the more i fix the little issues the more prevalent another problem shows up.

The engine acts weird from 1100 to 2100 with 1800rpm to be the worst.Its consistent on gas and petrol and through gears 2,3,4,5, especially under load.Above 2200rpm the motor appears to behave normally.
I tried the GAZ forum but they complain about my Russian and their answers are half gassed anyway.
This problem has been there since i bought the car , I often thought it was the gearbox shaking and wobbling(which it did), but i just got the box rebuilt and now i think it shows the problem a little more sharper when accelerating.

How do i narrow down this symptoms?
The symptom being a labored rev and often feels hesitant like the spark is missing.Punching the throttle seems to make the problem less noticeable.But still its there, 1800 rpm feels like 2 of the 4 cylinders are working.

have done already*
*new plugs
*Checked high voltage wires and boots.
*New coil packs.
*Cleaned crank sensor

[cors]

tested crank sensor and is within manufacturers specs.
http://youtu.be/6ws8EVQ6NjE

[Gilbertd]

The engine acts weird from 1100 to 2100 with 1800rpm to be the worst.Its consistent on gas and petrol and through gears 2,3,4,5, especially under load.Above 2200rpm the motor appears to behave normally.

It if doesn't run right on petrol, it will never run right on gas. So ignore the gas side of things for the time being and get it right on petrol first until then you are wasting your time. You may well find that it will then sort itself out on gas too and just need retuning as you have currently got it set to compensate for some other fault. At the moment you are trying to treat the symptoms and not the cause. As the problem is worse at certain revs but OKish (it's never going to be spot on because of what it is) over the rest of the rev range, it has to be something revs related. Is the mechnical advance in the distributor working properly? If it is sticking so not advancing the ignition timing early enough, you'll go through a patch where the ignition timing is horrendously retarded so it will be rough and gutless.

*Checked high voltage wires and boots.

Don't check them, replace them. Older carbon cored HT leads fail after a few years. They'll test fine with a meter but break down at high voltages.

By the way, went by your place yesterday. I would have dropped in to give you a hand but at 37,000 feet in a Virgin Atlantic Airbus A340, it wasn't really possible.......

[cors]

it has to be something revs related. Is the mechanical advance in the distributor working properly? If it is sticking so not advancing the ignition timing early enough, you'll go through a patch where the ignition timing is horrendously retarded so it will be rough and gutless.

Im also onto the same theory,but would it explain un burnt gas in the exhaust at idle(showed up again .
I just went for a long drive and jumped out of the car to find the exhaust stinking of gas again.

I did replace all the spark plug boots as i could only buy a pack of 4, The old ones were new from last winter when i was chasing the same problem but gave up.

The timing is,
crank sensor,
Electronic vacuum sensor wired to the brain box.
I replaced/checked the vacuum hoses to the sensor etc last night, so this adds to my disappointment today.
This morning the exhaust didn't smell but does again.
Ive looked for loose wires - last year added 2 new coils and new attachments to the wires thinking the problem was a bad coil.

Just checked the volts to coil.
Engine off 12.3V.
Engine running 13.2V

[Gilbertd]

If the mechanical advance is sticking, who is to say it isn't advancing and then not retarding again when the revs drop. But, hang on a minute, multiple coils would suggest no distributor so although it is equipped with a carb, it has a fully electronic ignition system? Is that right? Usually you'll find that a carb engine has a distributor and an injection one has multiple coils, but who knows with the Russians.....

Have you got any way of testing the vacuum sensor as that would be responsible for causing the ingition timing to be altered depending on revs/load.

[cors]

Its true , carb and Electronic ignition.
I have the ability to check the pressure sensor.

http://translate.google.com/translate?h ... F13_31.htm

[cors]

Although the old vacuum sensor did work, i need a special machine to make sure its still working 100% ,so i got a new one.
The problem still happens.
Any thoughts?

[cors]

All new plugs again and all new high quality wires/boots.The mechanic said the old ones were poor quality and will let you down.He also got into the brain box and said the box was set on "early start" or whatever he means. Anyway as i was skeptical the problem has now returned.I figured if i am killing plugs and leads then there must be a reason for it.

[mat_fenwick]

I'm not really sure this will help but it's a free check so worth a try!

When the problem occurs, switch off the engine and immediately shift into neutral and come to a stop. Take all the plugs out and post up a picture here, as a snapshot of how the engine is running at that particular time. In my experience it's more of a useful check on fuelling problems (which yours surely can't be as it does it on both fuels) but the condition/colour of the plugs may shed a little bit of light on things....

[cors]

That will be a tough one to do as the problem can be there 1 minute and the next gone. Every time i feel the problem happen i can guarantee that the lambda sensor is reading .050 lean.its like some plugs dont fire and let a clean charge through to the sensor.Then when i feel like the engine is running OK , the sensor will act normally giving various rich and lean conditions as throttle is used.

[madmart]

Hi Cors sorry to hear about the problems getting the van running right , BUT I had a mate who had a 1991 lwb Ford transit fitted with a 2.0 Pinto engine and on gas(similar basic system as yours ) he only got 3 to 3.5 miles per litre !!!! That is very near to your economy . Is the engine based on the Ford pinto ? I cannot see enough to say , also the mechanic might know the problem as he said that the ECU is stuck in early start , maybe he means COLD START , where the ECU advances the ignition for a cold start ( something that I feel might be needed in Russia ) but never goes back to a warmed up setting ? Let us know how you get on .