Jump to content
  • Welcome To Mopar1973Man.Com LLC

    We are a privately owned support forum for the Dodge Ram Cummins Diesels. All information is free to read for everyone. To interact or ask questions you must have a subscription plan to enable all other features beyond reading. Please go over to the Subscription Page and pick out a plan that fits you best. At any time you wish to cancel the subscription please go back over to the Subscription Page and hit the Cancel button and your subscription will be stopped. All subscriptions are auto-renewing. 

blue smoke and rough starting


Recommended Posts

so a few days ago i went to start my truck after work (sat 10 hours) and when i started it, it took 3-4 cranks instead of normal, ran rough for the first few rotations, then bright blue smoke was coming out of the exhaust.

it has done this every time ive started it since.

any ideas whats causing it? i need this fixed asap, vacation trip coming up soon!

also on a side note, my fuel pressure gauge has a mind of its own. between 20 and 30 psi. bounces occasionally, spikes, doesnt alter whether i floor it or at idle

Link to comment
Share on other sites

this thread was meant to be placed in the 24v powertrain section. sorry guys!

fyi, any ideas you have will be told to a shop, so please try to help me as cheaply as possible.

im still too nervous to work on the truck myself and also have no garage :(

Link to comment
Share on other sites

I moved it here for you so hopefully you can get all the assistance you need. Have you scanned it for codes? Also, your fuel pressure gauge, is it an electronic sender type or is it mechanical?

Link to comment
Share on other sites

fp gauge is electrical, isspro ev2, btw.

i have these codes

p1693

This is a companion code meaning there is/are other code(s) in either the ECM or PCM

p0462

This code is for the fuel guage Fuel Level Sensor Circuit Low Input possible causes:

- Faulty fuel level sensor

- Fuel level sensor harness is open or shorted

- Fuel level sensor circuit poor electrical connection

p0602

This code is for a faulty program not recognised by the ECM. Generally caused by a programmer and normally ignored.

im not sure how to tell if the grid heaters are working properly or if the IAT is reading right. how can i do this?

My answers to your codes are in blue. For the grid heater, when you first turn the key on (while waiting for the :wts: light to go out) is the volt meter down around 10 volts? When it first starts does the volt meter go up to 12+ volts and drop down and go up and drop down...... You get the idea..? If so they are functioning, but if not, then it would make for a rough start and some white smoke when first started cold.

Link to comment
Share on other sites

My answers to your codes are in blue. For the grid heater, when you first turn the key on (while waiting for the :wts: light to go out) is the volt meter down around 10 volts? When it first starts does the volt meter go up to 12+ volts and drop down and go up and drop down...... You get the idea..? If so they are functioning, but if not, then it would make for a rough start and some white smoke when first started cold.

oh okay yea, the grids arent the problem then. they are working properly.

someone mentioned possible valve seat issue? im taking it to a very good shop monday, hopefully i dont get screwed.. i am 4 hours away from my shop since i recently moved, of course this is when i need tools

would injectors cause this? or valve seat? anything i can check quick with little to no tools that anyone can think of?

Link to comment
Share on other sites

  • Owner

Cycle mine only once in 14*F weather today and started right up.

 

As for valve seat issue do a compression test to verify the cylinder and head health.

 

I wonder if the cetane of the fuel was just too low? I'm starting to wonder if fuels were changed over to weather fuel soon enough this year. I know I'm not a big fan of it but you might try a measured dose of cetane booster and see if that helps. But if it does it could be fuel cetane related and it could be compression related too.

Link to comment
Share on other sites

mine has always started with 1 cycle. doible cycling isnt the issue, cutting out power at 60-70, shakey like its sputtering. somethings sure going on

is it safe to run cetane booster with my 1oz/gal 2-stroke mix Michael?

i will tell the shop to do a compression test and maybe injectors if that doesnt work.

what was your thinking on the IAT sensor? maybe i could buy a scangauge from advanced auto

Link to comment
Share on other sites

mine has always started with 1 cycle. doible cycling isnt the issue, cutting out power at 60-70, shakey like its sputtering. somethings sure going on

is it safe to run cetane booster with my 1oz/gal 2-stroke mix Michael?

i will tell the shop to do a compression test and maybe injectors if that doesnt work.

what was your thinking on the IAT sensor? maybe i could buy a scangauge from advanced auto

Now you are starting to give some good clues. You are having some fuel delivery issues. Have you put a mechanical pressure guage on the verify the fuel pressure?

Link to comment
Share on other sites

i can still gain speed, but its not the same.

i dont have a mechanical pressure gauge unfortunately. ill get the shop to check

i can lug it and will not smoke at all. usually theres some black smoke if lugged.

at idle i hear a weird noise, almost a ping or buzzing

Link to comment
Share on other sites

All that sounds to me like you are not getting the fuel you used to. When was the last time the fuel filter was changed? I wonder if the lift pump is failing or has failed. I also wonder if your VP is getting ready to give up the ghost on you.

Link to comment
Share on other sites

checked oil level, it is actually higher than it was last time it was changed. and has a slight greenish color when wiped on a paper towell, but has had that coloration since i can remember.

 

what does the level being high indicate?

Link to comment
Share on other sites

Sounds like you are 'making' oil. In other words there is fuel getting into your oil. Pull your valve cover and look for leaks. The only other place that might leak fuel is the shaft on your VP.

Link to comment
Share on other sites

×
×
  • Create New...