unreliable ignition

[jayjay]

my car wont ever reliably start.. should i be resigned to the fact that it's a 20 year old car and will never be reliable? or is there actually something up?

the starter motor sounds fine. is just doesn't seem to want to turn over. like initially it will be really enthusiastic, but then just drop dead..

help?

[Jmac]

Mate you want to check the main earth onto the gearbox on that vehicle . They used to go green and causes high resistance causing all sorts of grief. Mate going from all the info you are giving that is a starting block for you , need more info, but like i say try that earth. Need all your info mate.
Cheers

[gpk_gti]

also try the switch that is under the radiator hosing that is entering the block,its a temp sensor switch...bosch... about $70

[Jarred]

hows the battery? voltage and water levels?

[Golf Loon]

Yeah I`d suggest battery first.

Also with kjet turn the ignition on til red lights and the pump pulses, then off and pulse the pump again. Then push the padal to the floor twice and turn it on.

Are you any nearer rego mate?

[static1800]

does it kick good once then go real slow like its got a flat battery?

[jayjay]

i have a cold start injector and all the connections were crappy so i cleaned all that up, and it started like instantly. but then i let it cool down and it just wont start again. =[ it's not that it's not turning over or that the starter motor isn't work.. i've got a retrofitted starter button and it just feels like i haven't disengaged the immobiliser

[jayjay]

battery and everything is fine. it'll get like 10 or so combustions, but then just stop and the starter motor will keep trying uselessly to turn it over

[Mischa]

i have a cold start injector and all the connections were crappy so i cleaned all that up, and it started like instantly. but then i let it cool down and it just wont start again. =[ it's not that it's not turning over or that the starter motor isn't work.. i've got a retrofitted starter button and it just feels like i haven't disengaged the immobiliser

lol immobiliser? where? with an immob it'll start and run for 3 seconds and then switch off.

[jayjay]

maybe not immobiliser... well it has to be something like that... i spose the key just turns on the fuel pump so it's like a rudimentary immobiliser. =p.

any ideas guys?

oh btw, it's a CIS 1.8 kjet

[Jmac]

Yes now that you have given more info sounds like the fuel pressure is leaking back on shut down mate. Try changing your fuel non return valve which is on the end of you fuel pump, im sure if you had a fuel pressure gauge on there , you would have no holding pressure, these non return valves are common on these mate. Turning over so much is you building up pressure again, and of course if you have low battery and bad earths they all add up to a poor starti g vehicle.

[86gti]

Heya.
Had this problem with my K-jet a cupla years ago......
Best thing to do is get a fuel pressure guage and run a few tests...
Mine turned out to be a faulty Main pump...
started fine when it was cold, but got jerky when it warmed up, also didnt want to start when it was warm.
......
the relay wont turn the pumps on untill RPM is registered...so turning ign on and off shouldnt Purge nor help at all, neither will pumping the accelerator unless a car has a carburettor..............

Also had the problem of poor starting not long ago, wind over fine some days, slow other days......was the connection to the starter motor..
got loose and daggy...made new leads up and now its all fine...

but if its the pumps etc???? Here is a part of a Kjet over view ive written up elsewhere.

PUMPS.....
Pick up Pump, Lift pump, transfer pump or what ever you wish to call it is the first pump to pick up the fuel in the tank.
Make shure this is working well...If this doesn't work well it will starve the Main pump and you will find yourself replacing 2 Pumps!!
(been there done that)

Testing this pump is fairly simple.
Find your Fuel pump relay.... This was no where near where it said it was in the bently manual so im guessing the US versions differ a bit from the European vehicles. My relay was stamped number "62" and was in the top row of relays on the left.
when you get it out you will see 2 large pins and 2 or 3 small pins (cant remember how many small ones..but they dont matter at this stage)
where the 2 lage pins fit into the relay holder is where we are looking
Grab a switch (toggle ones are best - 2 pole) solder wires to the poles and fit large spade bits on the end of the wires.
make shure the switch is off and plug the spades into the 2 LARGE slots in the relay holder.
dont turn it on yet!!!!!!(if its not off you will hear the pumps fire up when you plug it in, no harm done, just turn it off quick)
have a look under the car driver side just under where the back seat is....
you will see the main pump with a plug going into the top of it. It a std type plug that can be removed by pushing the wire clip at the top and sliding it off.
once you have done that we will find the Lift pump.
take up the carpet in the boot well. to the right and up a little from the spare wheel well you will see a plate with 3 screws in it.
undo them and take the plate off to reveal the top of the pump and Fuel guage sender.you will see 2 hoses, both with arrows.
one points in (returned fuel from system) one pointing out...one pointing out is the one you want...
Take the hose off it, and find another bit of hose that will fit over the outlet.
now we are ready to testthe delivery rate. Grab a mesuring cup that will hold at least 500cc and get ready to let the fuel go into it.
get some one on the switch ( ill do it for a tinnie or 2)...
flick the switch and leave on for 10 seconds
you should get at least 400cc / 13 and a half Oz. into the cup...
If you have..thats good news..if not......................
Replace it before the main pump decides to retire.
Try to use Genuine Bosch parts where ever you can . I am running a high pressure Carter Pump in mine and it seems to work fine although a bit more noise than the Bosch product.


.......................
then ontooooooooooooooo

Main Pump

In the MK2, the main pump is located in the smaller tank (reservoir)....
This pump is a roller cell pump, with the fuel entering the pump and being compressed by rotating cells that force it through the pump at high pressure. It will apparently pump upto 8 bar (120 psi) with a delivery rate around 4 to 5 litres per minute .....the system relies on pressure to run well....so this is one of the Main parts of the system.
Within the pump is a pressure relief valve that lifts off its seat at about 8 bar to stop the pressure incase the filter, fuel lines or other things become obstructed. The other end of the pump (out) is where the non-return valve is.... When the voltage to the pump is removed it closes the return and maintains pressure within the system... we get to that later
The operating pressure in the system is approximately 5 bar (75 psi) and at this pressure the current drawn on the pump is around 5 to 8 amps.
Apparently the inside of the pump (armature) will spark etc......!!!! sounds bad when fuel is passing in there...
But absence of Oxygen means no explosion! hahahaha....

To test your deliver rate of the main pump get under the bonnet and find the fuel return hose....
this hose returnes the fuel back to the tank that has been unused.
the K-jet system doesn't Pulse fuel into the manifold like an EFI set up....it is always injecting so there is always fuel being recurculated..
plug the main pump back in where you unpluged it to test the lift pump.......
the return line on mk2 is just infront of the firewall on the driver side (aus)...

this test also relies on the voltage at the main pump..so low voltage at the pump means a bit less delivery...
Ive got a chart here that is measured in cm3.... i dont recall what it translated to in OZ or cc...but look up a conversion chart to translate
see what sort of voltage you have at the pump between 10-12v is usuall...

now run the return line into a measuring cup (mid sized) from memory mine held about 17oz.
run the pumps from the switch for 30 sec and turn off.

at 10v you should have around 350-380cm3
at 11v you should have around 500-520cm3
at 12v you should have around 650-670cm3

Ill edit this later and give you measurements that make more sence..lol.

this is where i found a problem with my MK2 a while ago.
all my pressure tests were fine, but my delivery from the main pump was less than half what it should have been...
was hard to start when warm, would miss and carry on allot, and eventualy wouldnt start at all...
new pump had it running better than ever

If you plan on getting more indepth than this i would urge you to get a bently manual... (I got mine from Pitstop book shop in WA)

................
thats just some info from my daily diray. lol
give it a go, hope this helps u out.....

My pressure to the fuel dizzy was ok, but the flow rate was shocking........
i have both pumps instock if you need any...

[Jmac]

Just on that one remember the non return valve is on the pump and you may be throwing the pump away when the valve may be the drama. Good bit of info there

[Golf Loon]

Nice info, but it still pulses the pump if you turn the ignition on and dont start the car.

[86gti]

Just on that one remember the non return valve is on the pump and you may be throwing the pump away when the valve may be the drama. Good bit of info there

for shure Jimmy,
like i say, test all the pressures first...never replace things till you know for shure. lol...or it could end up being expensive.