2.2 KU starting issue - Page 2

Arch_80 · 10-05-17, 09:58 AM

Funnily enough the fuel tank and fuel systems well as the K-jetronic is where all my KK and some of my KU problems started and ended so get the fuel particulate free first.

Even after flushing or acid treating it could still be sending crap down the pipes and blocking up all the filters along the way. For example I was surprised at how many banjo connections have little gauzes in them. Anyway but yeah clean fuel is key.

simons2 · 09-06-17, 01:14 PM

OK so................
I've stripped and cleaned the metering head.
There is a small hole in the barrel that the metering piston goes in, I lined the hole up with the hole in the metering body.
Lined the steel gasket up with all the holes in the metering head and replaced the 'O' rings on the barrel.
Checked filters that sit in the top of the metering head as well.
I changed my fuel filter (again) and it was looking promising.
Adjusted so that when fuel comes up the threads in metering head, then turned it back half a turn.
Fuel pressure at cold start but still nothing at injectors?
Would the potentiometer cause a non start or just poor running?
Really feed up now and if no joy not sure what I can do with the old girl, shame to break her!
PLEASE HELP>

Colin Aitchison · 09-06-17, 09:50 PM

Hi Simons2, Just seen your post, never had a KU engined car, but I think all the K-jets run in the same way, If you have fuel getting from the tank to the metering head at around 6bar
and no fuel out of the injectors when you lift the metering flap that is strange, could the pressure relief valve in the metering be stuck open and the pump is pumping the fuel from the tank round the pipe work and back to the tank via the pressure relief valve, if this is the case the pressure at the injectors will be too low for the injectors to open.

simons2 · 10-06-17, 08:08 AM

Hi Colin. Thanks for the reply much appreciated.
I removed the pressure valve in the metering head yesterday to check that but its not it, its doing what it should do.
I've not got a pressure kit to test it so......
I'm starting to wonder if the 'new' second pump is knackered as well!??

M4rkp · 10-06-17, 09:24 AM

If you have fuel on the inlet pipe then this sounds like the control plunger in the fuel metering head -

when you say there is 'resistance' how much? - you should only feel the weight of the plate, there shouldn't be any force needed to move this plate as it is only air that moves it in operation.

Have a look at this - I know its a Volvo club article, but K-Jet is K-Jet.

https://www.volvoclub.org.uk/tech/fu...lInjection.pdf

Its quite a simple setup - but there are several things that need to happen at the same time to make it work - look at the page the shows the actual fuel distributor - you can see how the fuel flows internally.

Does the idle mixture screw turn? - try turning it a few turns ANTICLOCKWISE and see if you get any change in the air plate resistance.

You say that the fuel accumulator is making a noise - is it a sort of 'cracking' or 'twanging' sound? there is a small bolt head ( could also be a screw head) on one end of the accumulator, carefully undo this screw/bolt - if fuel comes out you need to replace the accumulator. This is not your immediate problem, however it will need sorting once you get the car running.

I've got fuel pressure measuring kit if you need to borrow it

Mark

simons2 · 10-06-17, 12:03 PM

Thanks Mark all appreciated.
The air plate is moving freely, I can feel a small resistance on the plunger and nothing as it drops down.
That's what's getting me, its a simple set up but not working.
I've looked at loads of Porsche, ford, Volvo, Merc sites and by all accounts the car should be running!
I fitted a new fuel accumulator just in case but it only works to hold pressure from cold/hot starts so even if the diaphragm in the old one was bust it would just have to crank longer before it started.
The idle screw,(in the sensor plate 3mm allen key??) yes that turns, I've had fuel flow increase and I can shut it off. I've set the control plunger at 0.60mm it coughed a few times but nothing now.
QUESTION does the pump have enough vacuum to suck it so it sort of sticks to the bottom of the tank thus restricting flow??????????????????

M4rkp · 10-06-17, 01:15 PM

I think you are going to have to go back to basics here -

Ideally you need to remove the fuel pump relay and bridge it with a switch so you have easy access to operation without cranking the engine.

First thing really is fuel pressure test - it is possible that the pump is delivering fuel in free air but not able to produce enough pressure in a closed system -

Have you checked flow rate? - remove the supply line at the metering head - put the pipe in a container and activate the pump - you should get around 1400ml in 30 secs.

What happens if you disconnect ALL of the injector pipes at the metering head and then activate (briefly!!) the pump? - do you get anything?

Also do the same with the WUR -

I know its frustrating - trust me i've been there - but steady away and you will sort it.

As i said - I have the kit to measure system pressure and control pressure, you are more than welcome to borrow it.

simons2 · 10-06-17, 03:53 PM

Hi Mark
OK not checked flow rate like that but I can.
I did get fuel at the metering head in all 5 chambers then no pressure once injectors connected.
That's very kind of you I may take you up on that offer as a last resort.
I've gone back to the tank this afternoon checked fittings and pipes for splits.
Can anyone tell me, the return flow pipe back to the top of the tank connects to the big white 'cap' that then joins a pipe in the tank which appears to circulate the fuel to the bottom of the tank (I blew through the pipe and it bubbles) is that correct? Is there a filter in there somewhere?
Thanks again.

M4rkp · 10-06-17, 04:36 PM

Hi Simons2
The return pipe just deposits the fuel back into the tank at low level- there is no filter in this line as it is a closed system, the only filter is in the feed line - the feed line also has a non return valve ( inside the tank) to stop any fuel draining out of the pump and line when the engine is not running.

By the sounds of it there is not enough pressure to get the fuel out of the injectors- and seeing as though there is no visible sign of pools of fuel on the floor I would tend to sway towards your fuel pump impellor being faulty.

What car is it you have exactly ? - I know its a KU but that engine was fitted to several models

Mark

simons2 · 10-06-17, 04:47 PM

I agree and think surely a second new pump cant be duff.....but maybe

!
100 Avant Quattro.
The issue started when it ran low on fuel, the gauge said I had 1/4 tank but the sender was stuck.
That's fixed now, but issue since.
Thanks for the help thus far

, will work on it again next week and see where I get.
Another Q. Can you buy just the seal/ 'O type ring' that fits to the screw adjuster that holds the metering plunger in place/adjusted anywhere?????

10-06-17, 04:47 PM	#20
simons2 Grown up member Classic Audi Club Member Join Date: Jun 2012 Location: ireland Posts: 291	I agree and think surely a second new pump cant be duff.....but maybe! 100 Avant Quattro. The issue started when it ran low on fuel, the gauge said I had 1/4 tank but the sender was stuck. That's fixed now, but issue since. Thanks for the help thus far, will work on it again next week and see where I get. Another Q. Can you buy just the seal/ 'O type ring' that fits to the screw adjuster that holds the metering plunger in place/adjusted anywhere?????

10-05-17, 09:58 AM	#11
Arch_80 Grown up member Join Date: Jan 2012 Location: Devon, not enough audi's here Posts: 35	Funnily enough the fuel tank and fuel systems well as the K-jetronic is where all my KK and some of my KU problems started and ended so get the fuel particulate free first. Even after flushing or acid treating it could still be sending crap down the pipes and blocking up all the filters along the way. For example I was surprised at how many banjo connections have little gauzes in them. Anyway but yeah clean fuel is key.

09-06-17, 01:14 PM	#12
simons2 Grown up member Classic Audi Club Member Join Date: Jun 2012 Location: ireland Posts: 291	OK so................ I've stripped and cleaned the metering head. There is a small hole in the barrel that the metering piston goes in, I lined the hole up with the hole in the metering body. Lined the steel gasket up with all the holes in the metering head and replaced the 'O' rings on the barrel. Checked filters that sit in the top of the metering head as well. I changed my fuel filter (again) and it was looking promising. Adjusted so that when fuel comes up the threads in metering head, then turned it back half a turn. Fuel pressure at cold start but still nothing at injectors? Would the potentiometer cause a non start or just poor running? Really feed up now and if no joy not sure what I can do with the old girl, shame to break her! PLEASE HELP>

09-06-17, 09:50 PM	#13
Colin Aitchison Senior Member Classic Audi Club Member Join Date: Dec 2013 Location: Back home in Tillicoultry Posts: 1,350	Hi Simons2, Just seen your post, never had a KU engined car, but I think all the K-jets run in the same way, If you have fuel getting from the tank to the metering head at around 6bar and no fuel out of the injectors when you lift the metering flap that is strange, could the pressure relief valve in the metering be stuck open and the pump is pumping the fuel from the tank round the pipe work and back to the tank via the pressure relief valve, if this is the case the pressure at the injectors will be too low for the injectors to open.

10-06-17, 08:08 AM	#14
simons2 Grown up member Classic Audi Club Member Join Date: Jun 2012 Location: ireland Posts: 291	Hi Colin. Thanks for the reply much appreciated. I removed the pressure valve in the metering head yesterday to check that but its not it, its doing what it should do. I've not got a pressure kit to test it so...... I'm starting to wonder if the 'new' second pump is knackered as well!??

10-06-17, 09:24 AM	#15
M4rkp Grown up member Classic Audi Club Member Join Date: Feb 2013 Location: Sometimes Roberttown - sometimes Surrey Posts: 194	If you have fuel on the inlet pipe then this sounds like the control plunger in the fuel metering head - when you say there is 'resistance' how much? - you should only feel the weight of the plate, there shouldn't be any force needed to move this plate as it is only air that moves it in operation. Have a look at this - I know its a Volvo club article, but K-Jet is K-Jet. https://www.volvoclub.org.uk/tech/fu...lInjection.pdf Its quite a simple setup - but there are several things that need to happen at the same time to make it work - look at the page the shows the actual fuel distributor - you can see how the fuel flows internally. Does the idle mixture screw turn? - try turning it a few turns ANTICLOCKWISE and see if you get any change in the air plate resistance. You say that the fuel accumulator is making a noise - is it a sort of 'cracking' or 'twanging' sound? there is a small bolt head ( could also be a screw head) on one end of the accumulator, carefully undo this screw/bolt - if fuel comes out you need to replace the accumulator. This is not your immediate problem, however it will need sorting once you get the car running. I've got fuel pressure measuring kit if you need to borrow it Mark

10-06-17, 12:03 PM	#16
simons2 Grown up member Classic Audi Club Member Join Date: Jun 2012 Location: ireland Posts: 291	Thanks Mark all appreciated. The air plate is moving freely, I can feel a small resistance on the plunger and nothing as it drops down. That's what's getting me, its a simple set up but not working. I've looked at loads of Porsche, ford, Volvo, Merc sites and by all accounts the car should be running! I fitted a new fuel accumulator just in case but it only works to hold pressure from cold/hot starts so even if the diaphragm in the old one was bust it would just have to crank longer before it started. The idle screw,(in the sensor plate 3mm allen key??) yes that turns, I've had fuel flow increase and I can shut it off. I've set the control plunger at 0.60mm it coughed a few times but nothing now. QUESTION does the pump have enough vacuum to suck it so it sort of sticks to the bottom of the tank thus restricting flow??????????????????

10-06-17, 01:15 PM	#17
M4rkp Grown up member Classic Audi Club Member Join Date: Feb 2013 Location: Sometimes Roberttown - sometimes Surrey Posts: 194	I think you are going to have to go back to basics here - Ideally you need to remove the fuel pump relay and bridge it with a switch so you have easy access to operation without cranking the engine. First thing really is fuel pressure test - it is possible that the pump is delivering fuel in free air but not able to produce enough pressure in a closed system - Have you checked flow rate? - remove the supply line at the metering head - put the pipe in a container and activate the pump - you should get around 1400ml in 30 secs. What happens if you disconnect ALL of the injector pipes at the metering head and then activate (briefly!!) the pump? - do you get anything? Also do the same with the WUR - I know its frustrating - trust me i've been there - but steady away and you will sort it. As i said - I have the kit to measure system pressure and control pressure, you are more than welcome to borrow it.

10-06-17, 03:53 PM	#18
simons2 Grown up member Classic Audi Club Member Join Date: Jun 2012 Location: ireland Posts: 291	Hi Mark OK not checked flow rate like that but I can. I did get fuel at the metering head in all 5 chambers then no pressure once injectors connected. That's very kind of you I may take you up on that offer as a last resort. I've gone back to the tank this afternoon checked fittings and pipes for splits. Can anyone tell me, the return flow pipe back to the top of the tank connects to the big white 'cap' that then joins a pipe in the tank which appears to circulate the fuel to the bottom of the tank (I blew through the pipe and it bubbles) is that correct? Is there a filter in there somewhere? Thanks again.

10-06-17, 04:36 PM	#19
M4rkp Grown up member Classic Audi Club Member Join Date: Feb 2013 Location: Sometimes Roberttown - sometimes Surrey Posts: 194	Hi Simons2 The return pipe just deposits the fuel back into the tank at low level- there is no filter in this line as it is a closed system, the only filter is in the feed line - the feed line also has a non return valve ( inside the tank) to stop any fuel draining out of the pump and line when the engine is not running. By the sounds of it there is not enough pressure to get the fuel out of the injectors- and seeing as though there is no visible sign of pools of fuel on the floor I would tend to sway towards your fuel pump impellor being faulty. What car is it you have exactly ? - I know its a KU but that engine was fitted to several models Mark