cold start question - page 1 - IDI Engine - VWDiesel.net The IDI, TDI, and mTDI source.

cold start question by vwroadkill on 10 Nov, 2012 05:32
here we go.. again I am new to diesels. I recently set my timing. ambient temps those days was in the mid 90's, now as the weather has the temp dropping in my area to the low 30's at night, I am having a difficult time starting and stay running . unless I pull cold start out wait for glow plug light to go out, attempt to start. it catches and dies. do this two or three time and then maybe. at the fifth attempt it will catch and run. but I cant figure why.. do I need to reset timing. plug in engine warmer.. is there some vodoo I am missing.. chicken bones .. maybe slaughter the neighbors cat to pay homage{ will do that anyways} lol.. thoughts ideas..
Dan
#1 by TylerDurden on 10 Nov, 2012 05:49
Cover the basics:
#2 by vwroadkill on 10 Nov, 2012 05:52
thanks the basics are covered.. Iam just skeptical that I timed the engine for one temperature. and will have to time it for another.. cause it wont start like it did before..
Dan
#3 by TylerDurden on 10 Nov, 2012 06:22
Any white/grey smoke?

Colder ambient temps can exacerbate tuning issues; an engine tuned for easy starting in the cold should not need re-tuning for warmer seasons.

There are folks who assert that older (non-rebuilt) engines can benefit from additional advance.

I time "by ear", turning the IP to the cusp of increased clatter (@idle, engine warm), then back-off a hair.
#4 by vwroadkill on 10 Nov, 2012 06:46
white smoke.yes..it does this ALOT. Does this mean I have it to fat.. heavy fuel.. should I lean it out... most of my experience is on aircraft engines, jets mostly.. so I am getting it just not like I want ..

I hear the clatter as it starts and then is smoothes out..
would I benefit from getting my injectors replaced... think vw installed these.. only 137k on the clock but the car was sitting before I bought it and I have driven it maybe one tankful at best.
pump is new
#5 by TylerDurden on 10 Nov, 2012 08:27
White smoke usually indicates retarded timing. Dark smoke usually means overfueling.

I distinctly hear clatter until the engine is up to temperature.

Injectors have to be pretty bad to significantly effect starting.
#6 by CarlosA on 10 Nov, 2012 11:12
Part of the cold start process when very cold is to have the pedal floored. I use this, get it started, pull the cold start, and still feather the throttle for a while as it warms up. Same on both my cars.
#7 by bbob203 on 10 Nov, 2012 14:24
Quote from: vwroadkill on 10 Nov, 2012 06:46
most of my experience is on aircraft engines, jets mostly.. so I am getting it just not like I want ..

Do you happen to work for us airways? I notice you live near charlotte.
#8 by bbob203 on 10 Nov, 2012 14:25
Quote from: CarlosA on 10 Nov, 2012 11:12
Part of the cold start process when very cold is to have the pedal floored. I use this, get it started, pull the cold start, and still feather the throttle for a while as it warms up. Same on both my cars.

THIS is a great tip. But i only find it neccesary down below 15 f. Sounds like you could advance your timing a hair and it would be good.
#9 by JamesT on 10 Nov, 2012 21:47
I don't understand this phrase:
Quote from: vwroadkill on 10 Nov, 2012 05:32
I am having a difficult time starting and stay running . unless I pull cold start out wait for glow plug light to go out, attempt to start. it catches and dies.
It's not an unless. That is the procedure for starting in cold weather. If you do not pull the cold start and wait for the glow plug light to go out, it will be difficult to start.
#10 by burn_your_money on 11 Nov, 2012 03:36
On my mom's 84 Jetta I advance the timing for the winter. I like the quietness of the retarded timing but it just doesn't cut it in the winter.
#11 by vwroadkill on 11 Nov, 2012 04:40
ok.. lot of questions and input, I will answer.
the normal range of temps here in the southeast US get down to a bismal 20f at worst... so I didnt think I would have to worry about cold weather procedures. noted.. I will use the plug that is hanging off the back of the engine to warm it up. lol.
I do not work for USAIRWAY's. would like to. but I work for the AirForce and have for the last 28 years. Im a C-130 mech.
I will try the pedal floored method to start and use the cold start knob to keep it running method,
as well as add some advance to the IP.
thanks for the info..
I will post some pictures of the upgrades to my truck. new front sheetmetal. floor pans , wheels tires , interior coil overs.
Dan
#12 by TylerDurden on 11 Nov, 2012 05:59
I used the same method on my 86 TD with shot rings... Heater, floored, glow, crank and pull CS when the engine catches. The cranking would bog-down if the CS were pulled beforehand.

All my other 1.6 require the CS pulled to light-off quickly. I'm pretty sure they all have good compression.
#13 by mystery3 on 11 Nov, 2012 22:46
I could be wrong about many things this included but I thought to start a cold engine regardless of ambient temps you first want to pull the cold start handle, burn the glow plugs until the indicator light goes out then start the engine. Drive normally for a few minutes and push the cold start lever back in as soon as the temps gauge begins to move off the resting position. I'm fortunate never to have to start in temps below the high 20's F so don't have any experience starting in truly cold weather.
#14 by CarlosA on 11 Nov, 2012 23:35
Quote from: mystery3 on 11 Nov, 2012 22:46
I could be wrong about many things this included but I thought to start a cold engine regardless of ambient temps you first want to pull the cold start handle, burn the glow plugs until the indicator light goes out then start the engine. Drive normally for a few minutes and push the cold start lever back in as soon as the temps gauge begins to move off the resting position. I'm fortunate never to have to start in temps below the high 20's F so don't have any experience starting in truly cold weather.

Yeah you can pull it ahead of time but like Tyler said, if its very cold it will bog down. To be honest I didnt even run a cold start cable last winter and just spent a few more seconds feathering the throttle before running back in the house for 5 minutes...