Author Topic: Rough idle in the morning (when cold).... What could it be?? (Read 4406 times)

ThumperTheRabbit · « **on:** October 18, 2004, 11:36:59 am »

My little rabbit has been great so far. It has 133k miles on it and gets 47 mpg when I cruise at 60mph... My only worries are these: When I start the car in the morning, it idles really rough and smokes a combination of whitish blue smoke... If I rev it up the smoke goes away but you can hear the engine "missing"... After the engine is warm, it idles like a dream... Smooth and almost no smoke (blue or otherwise). However it does spit out a nice cloud of Black smoke (fuel) when you "jab" the accelerator on the highway

:D... I use that to remove tailgaters

:D...

So would anyone have any suggestions on what this could be?? I changed the fuel filter already and that didn't help... I was thinking possibly injectors, but I don't know what the life is on the average 1.6l NA injectors... If anyone has any inputs I would greatly appreciate it!!

This is my second rabbit. My first one I got when I was 17 and ended up replacing the headgasket myself... However, something happened (didn't get the right headgasket??) and the car would never start again

... I am glad that I found a group of people that know these engines. I hope to learn lots!!!

Educate me!!!!

:D

okumaguru · « **Reply #1 on:** October 18, 2004, 07:30:53 pm »

Sounds like you are describing my Rabbit also. I didn't notice it when the weather was warm but now that it's getting cooler, I've been noticeing the exact smae thing.
Could it be common with the diesels?
Thanks
Tim

DieselsRcool · « **Reply #2 on:** October 19, 2004, 11:25:14 am »

It's that time of year again when the bad glow plugs become obvious. Pull your injectors and look down the holes while the glow plugs are on. Chances are you'll find one bad one.

BlackTieTD · « **Reply #3 on:** October 19, 2004, 01:11:36 pm »

i second... check glow plugs. have fun!

gldgti · « **Reply #4 on:** October 21, 2004, 01:06:58 am »

also, timing might be a bit retarded. infact, advanced timing helps prevent this happening even if your timing is normal. you'll notice if, once its started, you push in the cold start valve, it will 'miss' more often.

okumaguru · « **Reply #5 on:** October 21, 2004, 05:17:00 am »

Which way is advancing the timing? Moving the pump towards the block or towards the radiator?
Tim

DieselsRcool · « **Reply #6 on:** October 21, 2004, 08:30:13 am »

Move the top of the pump back toward the engine to adv the timing.

Dr. Diesel · « **Reply #7 on:** October 22, 2004, 11:45:32 am »

if you decide to pull the injectors, don't forget to install new heat shields (correctly!!) as they're one-shot deals, and very cheap from the dealer.
Alternately, if you have an appropriate ammeter, you could meter the current being drawn. I believe it's 8 amps per plug. So, if it's drawing only 24, you know you've got one burnt out. Also, you could remove the power bus from the glowplugs and meter each plug individually with an ammeter or and ohmmeter to ground.

dieselpower · « **Reply #8 on:** October 23, 2004, 12:05:06 pm »

this is what i do to check the engine.
i start it when it's cold, then if one cyliner is missing i start crackin the injection lines one at a time. and when you crack one and the engine's idle stays the same, thats the cylinder thats giving you problems. then you can check that glowplug, compression, or injector to find the problem of why it dos that when its cold. it's most likely the glow plug and i find that if i overtighten them it makes them burn out faster.
hope this helps

Mark