Rough Idle

[mansvw]

Hi all,

I'm trying to get down to the cause of the problem,...

would a blocked injector cause such rough idle, which in turn cause the car to stall? :cry:

[jtanguay]

hmm possibly but check the fuel delivery system first.. filter etc.  bubbles in the system will cause rough idling too.

[mansvw]

the filters new, no visiable air bubble in the clear fuel lines... i've checked delivery to the injectors at the union nut at the top of the injectors by loosening the nut and turning the ignition key without the gas pedal been touched, diesel can be seen at this point.

i may just be the injectors (blocked)?

[jtanguay]

with the amount of pressure going to the injectors, its hard to believe that they will be blocked... sometimes they can 'stick' and that is when a good diesel purge could possibly free them.

[mansvw]

all changed for new ones now ......

[jtanguay]

how's your idle now?

[mansvw]

it was was still rough and switchig off, what a waste of money...but has to be done, it the process of fault finding...didn't help the idle one bit tho .

what about the cold start on the injector, could it be sticking?

[jtanguay]

i doubt the cold start would do it...

if you can get your hands on a nice little diesel lift pump, i'd say try it.

supposedly they can 'wake up' tired old injection pumps.  i think the pump may be starving for fuel somewhere along the way...

but in the meantime, try running the motor off of a can of diesel.  that will eliminate the lines going back to the tank as the culprits.

[55mpg06]

Realy dumb question, did this problem just develop, or did is come after changeing or adjusting somthing, or even filling up? Also have you done a quick timing check since, I've found that could do it. I know you probably have done all this but I thought I would ask.

[saurkraut]

http://www.vwdiesel.net/phpBB/viewtopic.php?t=8362

Same author

[55mpg06]

Thanks Saurkraut, that sheads a little light on things. Mansvw, the symptoms of the problem you are having appears to be exactly the same as what baffled me the first time I timed a VW Diesel.  

To look at the marks on the flywheel, you have gain access to the "inspection hole" on the transmission case.

There is a plug that pulles straight out of a plastic sleeve (plug almost looks like it was translucent at one time and sleeve lookes like it could accept a really big allen wrench) This is NOT what you want to remove.  You would see a notch cut in plastic rather than a metal arrow pointing down. This is not the correct refrence mark to have the flywheel line up with and you couldn't see the correct flywheel marks anyway.

Instead, the plastic "sleeve" that the plug fits into needs to be treaded out (like a plastic bolt) and that will then reveal a metal arrow pointing down. There will be a spot on the flywheel that has multiple markings (4 to 6 i think) line up the arrow with the one that looks like a "0" cast directly beside it.

Anyway, this is what had fooled me before. :roll:  Hope this helps. Keep us posted.

[burn_your_money]

How are your motor mounts?

[mansvw]

ill post some pics later on....

IT'S STILL BROKE  

55mpg06 - thanks all, got the timimg belt on and set up the flywheel and crank etc. i will give you a full feedback 2nite. the can still doesn't want to idle correct and still smokes.

so far:

new glow plugs x4
new injectors x4
new timing belt and tensioner
checked idling speed valve resistance


i narrowed it down to the pump timing and pump itself.

does anyone know what the tool for checking the injector pump compression?
and would any one have any suggestions on the pump it self?  the cover for timing control, would it be worth opening and cleaning?

[mansvw]

i've taken a few pics of the timing tools that i used or tried to use...

first set of timing tools that i bought were...









these two tools were wrong, the pin won't fit anywhere in the injection pump pulley

so after abit more research i found out that my injection pump is a two piece pump and requires a different set of tools..... below








  perfect set of tools.... only if i knew the first time round, that would have saved me loads of time. anyways that the learning curve for ya...


as you may of read in the earlier post... im now 100% sure the fault is in the pump and not anywhere else. i've posted the pic below and was wondering if it would be worth removing this cover and having a look to see if i can find anything broken?

Any injection pump guru's out there??
the red arrow, sorry for they distorted pic

[jimfoo]

Not positive, but I think that a spring that has to do with the timing lives in there, as well as some other parts.  Look here if you have high speed.
http://www.vwdiesel.net/phpBB/viewtopic.php?t=4353
It shows the IP in great detail.