Author Topic: Just a couple Q's. TDI isn't my game (Read 4952 times)

Smokey Eddy · « **on:** January 30, 2009, 05:58:02 pm »

My parents 2000 tdi has some bizzare quirks.
Every so often it will completely screw up with driving ability (be really really slow and have seemingly no boost) and they (always) take it to the stealership and they [the dealership] say they remove, literally, a pile of gunk from the intake. It looks like a mix of tar with like ... broken charcoal bits in it. (I saw the pile once at the dealership.)

As of late it's been around zero and a low of -5c at night and it will stumble starting so i checked all the GPS and they're all fine.

Any ideas? jtanguay mentioned in another post (i read just now) about some sort of valve that could be stuck? Something to do with running while cold.

Thanks!

jtanguay · « **Reply #1 on:** January 30, 2009, 06:13:19 pm »

Quote from: "Smokey Eddy"

My parents 2000 tdi has some bizzare quirks.
Every so often it will completely screw up with driving ability (be really really slow and have seemingly no boost) and they (always) take it to the stealership and they [the dealership] say they remove, literally, a pile of gunk from the intake. It looks like a mix of tar with like ... broken charcoal bits in it. (I saw the pile once at the dealership.)

As of late it's been around zero and a low of -5c at night and it will stumble starting so i checked all the GPS and they're all fine.

Any ideas? jtanguay mentioned in another post (i read just now) about some sort of valve that could be stuck? Something to do with running while cold.

Thanks!

the EGR valve will make the car run like complete *** if its stuck open, and the car is fully warmed up. essentially it is 'choking' the motor. had it happen on my dads caravan. car ran fine at speed, but would stall when fully up to temperature.

at worst it could be the injectors/pump, and at least it could be the fuel filter, or an air leak in the system (if not already changed by the stealer). best mod for your parents vehicle would be to vent the crankcase gases out of the intake stream. then the sooty carbon won't stick (not as much anyways) to the intake system.

my car will start down to about -16C or even lower just fine without glow plugs. the problem is that if i let it sit overnight, air leaks into the fuel system making it very difficult to start. after about 2 hours it starts up no problem (at -16C any heat in the motor is completely gone...) and after 2 hours it slowly starts to get harder to start. i'm reluctant to track down the problem until i get the heater core changed out... :roll: :cry:

Smokey Eddy · « **Reply #2 on:** January 30, 2009, 06:19:28 pm »

so, the hard starting is a line/injector/pump sealing issue.
It still gets killer mileage so im thinking air in the lines...

i don't think its the EGR. Where should i vent the crank case to? the ground? haha

What are some other pretty simple mods you suggest?

jtanguay · « **Reply #3 on:** January 30, 2009, 06:39:11 pm »

Quote from: "Smokey Eddy"

so, the hard starting is a line/injector/pump sealing issue.
It still gets killer mileage so im thinking air in the lines...

i don't think its the EGR. Where should i vent the crank case to? the ground? haha

What are some other pretty simple mods you suggest?

the crankcase mod is probably the best(only) one i know of.. best place to route the crankcase gases is back into the sump, after being in some sort of filter.

Smokey Eddy · « **Reply #4 on:** January 30, 2009, 06:57:47 pm »

sounds like a little too much modding on a car that isn't technically mine...

I try and maintain it without my dad knowing. He'd go nuts if he knew i changed out two burnt out GPs. My mum doesn't mind tho. She covered me the cost of the gp's. Drilling and taping the sump i have the tools to do but i don't think i should do that quite yet. Maybe if he goes away for a week or something :roll:
Because it has that plastic "TDI 1.9" cover over it he thinks it's too new and advanced for me to even touch.

jtanguay · « **Reply #5 on:** January 30, 2009, 07:32:30 pm »

Quote from: "Smokey Eddy"

sounds like a little too much modding on a car that isn't technically mine...

I try and maintain it without my dad knowing. He'd go nuts if he knew i changed out two burnt out GPs. My mum doesn't mind tho. She covered me the cost of the gp's. Drilling and taping the sump i have the tools to do but i don't think i should do that quite yet. Maybe if he goes away for a week or something :roll:
Because it has that plastic "TDI 1.9" cover over it he thinks it's too new and advanced for me to even touch.

hehe figures.. you don't necessarily have to drill the block to drain there though... i think that year TDI might have another drain you could T into. maybe someone else here has installed one on a TDI?

Smokey Eddy · « **Reply #6 on:** January 30, 2009, 08:22:18 pm »

i didn't mean drill the block i just meant the oil pan.

foxracer1 · « **Reply #7 on:** January 30, 2009, 09:32:55 pm »

The crankcase vent(breather on valve cover) can not be vented to the pan. It needs to be vented to the ground using a filter so no dirt is drawn back in. Or you could eliminate the EGR. But you would then get an intermitent code.

Smokey Eddy · « **Reply #8 on:** January 30, 2009, 09:37:31 pm »

augh sounds like a bit outta my ball game

jtanguay · « **Reply #9 on:** January 30, 2009, 09:57:54 pm »

Quote from: "foxracer1"

The crankcase vent(breather on valve cover) can not be vented to the pan. It needs to be vented to the ground using a filter so no dirt is drawn back in. Or you could eliminate the EGR. But you would then get an intermitent code.

many systems actually drain back into the pan, although if the oil is really dirty it might not be such a good idea unless it is somehow filtered. the system on 1.9's (mine included) have a special plastic pipe going from the breather to the block so that oil can drain down. i don't think that the ALH came with this though..

some people use catch cans to accumulate the oil, and then drain it periodically.

smokey i meant drill the oil pan and not block :oops: :lol:

foxracer1 · « **Reply #10 on:** January 31, 2009, 07:20:55 am »

I just mean the crankcase must breathe it needs to vent. A fresh engine could get by with a filter on the valve cover.

the caveman · « **Reply #11 on:** January 31, 2009, 10:10:09 am »

Is it possible to define what you mean by loosing driving ability and seems to lose boost. If the loss of power is intermittent, and comes back after the car is shut down, then it could be the ECU is going into failsafe mode. In some instances the ECU will pull back timing, remove all wastegate functions [okay it's a VNT but just trying to keep it simple] etc. If it doesn't come back after an ignition cycle then maybe the fuel filter is beginning to plug, which may also cause the hard starting cold. You don't mention the check light coming on and if so, it has to be something more basic. Lots of others may disagree with me on this one, but unless the intake is completely plugged, i wouldn't even look there. When i was at the dealer and since i left [we are still on speaking terms] they have cleaned 3 intakes since 2000. Now it's possible the EGR valve in the "throttle body" is sticking, but that would definitely set a DTC. But while at that same place the "thottle " plate which serves to make sure the motor stops the instant the key is turned off can be partially at fault. Look to see if the lever is still attached to the solinoid. Maybe it's flopping around if it's disconnected, cause intake restriction and also the no/poor starting.
The other issue with the no/poor starting is that when the timing belt was replaced[i'm assuming it's been done at least once by now] then the pump timing may be off. On those TDI's it has to be set by using something like Vag-com to see where the timing is in relation to engine temp. I recently had a comeback on one that i had done where it was hard to start because i didn't wait long enough for the engine to get hot and so the timing was set too low.

Smokey Eddy · « **Reply #12 on:** January 31, 2009, 12:46:47 pm »

Wow nice response. Okay. Well it isn't having the weak driving right now. It just takes probably 3-4 revolutions before it starts.

we can all ignore what i said about the weak driving thing.

no dtc light is present.

where is this lever you speak of? like i said i really don't know anything about these engines.

the caveman · « **Reply #13 on:** January 31, 2009, 02:38:19 pm »

The long cranking sounds to me to be timing is not quite right.
The lever is on the EGR/throttle body at the back. There is a small vacuum actuator with a hose attached to it. If you take the hose off ,you will see the flap. But before that , make sure it's not flopping around. If you want, it wouldn't hurt to spray some carb/intake cleaner or brake cleaner just where the flap touches inside to clear out the gunk. The way it works is when the ignition is turned off the solenoid opens, causes vacuum to go to the vacuum can, which then pulls the flap closed, chokes the intake ,engine stops. But right after the flap should reopen. Sometimes it stays closed, and engine no workie.

jackbombay · « **Reply #14 on:** January 31, 2009, 03:09:43 pm »

Quote from: "foxracer1"

But you would then get an intermitent code.

FWIW, if you do the VAG-Com EGR adaptation and then eliminate the EGR system you rarely get a code, and even then it typically only happened to me at low temps, around 0*F, and high altitude, above 5,000'.