My uncle just drove several hundred miles to get here and he noticed that after long downhills under minimal throttle his 01 will make blue (not white or black) smoke for several seconds after getting back on the accelerator.

He's been on several trips with lots of downhills etc and has never seen this before. Truck has about 80k miles on it.

Fuel mileage was also lower than usual (13mpg highway vs 18mpg usual). Power seems to be unaffected.

We're a little concerned that maybe something needs to be fixed before making the trip back.

Any thoughts?

 

Check lift pump pressure. Also check the MAP and IAT sensor to make sure they are within spec. Last but not least, some of the symptoms listed have been related to a failing VP...

 

What has the temperature been there when he noticed it?
I know mine will idle with blue smoke when it is really cold- almost like the fuel isn't completely burning.
If his engine temps aren't up, he will see the blue smoke and lower mileage. If the temps are low, the thermostat will probably need to be replaced, or ensure that there is adequate mixture in the cooling system.

 

turn the key on off on off on and watch the odometer till it goes through all the codes back to the milage. Write any codes down and then post em up....

 

Aside from the smoke has there been any other symptoms such as the dead pedal or loss of power even for very short periods of time, even seconds?

Also the usual question, is there a fuel pressure gauge to keep an eye on consistent fuel delivery?

As we found out the hard way, most fuel metering issues are controlled by the dreaded VP. We went through every sensor, and the APPS, none helped our smoke and dead pedal issues.

If you click on our call sign you can bring up our smoking issues. Hopefully not the same. On the plus side we were lucky that this VP never did fully die, even after months. We finally put it out of it's / our misery! Now it's purrs just fine and only our wallet retains any pain!

 

The truck in question (pop's ram) had a new lift pump installed at approx 40k on its last trip to colorado. it now has 84k on it. we know where the iat is but where is the map sensor and do we just spray them off with carb cleaner we did the key on/ key off test that BLACKDIESEL explained and we got the following results:
p-pcu
p-1693
p-done
p-ecu
p-0216
p-done
we called our dealer back home and the tech said it sounds like time for a new lift pump again. just in my short time on this site I am starting to see that factory lift pumps are the thorn in everyones side. my 2003 has its factory plastic one on the motor but the tech said that when it goes away he will put a electric one in the tank and that pops truck will get the same thing when we all get home. I know pop probably dont have a choice but should I keep the plastic one or change (i do plan to do more to my 03)
thank yall for all the help

 

My mileage has been down too and the power some as well. I just checked for codes and got:

p pcu
p 1693
p done
p ecu
p 0216
p 0238
p 0236
p 0237
p done

Where can I get these defined? Any ideas?

Thanks, Steve

 

Mine did that when the vp44 went out. p0216 was showing at the time.

 

I found the code definitions at
http://www.troublecodes.net/OBD2/Pcodes.shtml#500
but need to know if I can clear them by disconnecting the battery and tunring the key on for a while. I'd like to clear them and see what returns befor calling the dealer.

Thanks, Steve

 

I just took the truck in question to a dealership to have the codes checked. the tec said that he would reset the codes and see if the prob came back since the check engine light never came on. the tech said that it could have been bad fuel or something simple like that. I found that the waranty was out by several months and another tech jumped in to tell that it needed a new pump and that it would be between $1,700.00 to $2,000.00 but he happened to have a good used pump he would put on for $400.00 out the door. the question is the truck is now running fine and no smoke should we wait for the pump to die or jump on the great deal.

 

$400.00 will include how long of a warranty? If it does not have a warranty, I would be wary of that deal. You can get a complete 1/2" fuel system for about that and do it yourself.
Let's back up- What pump are you talking about? If it is the LP you are talking about, 1700-2000.00 is WAY out of line. If that is the VP for 400.00 installed, I would do that. I would see if they can hold that pump for you for 1 month so you can drive it again and see if the same code P0216 comes up or if it dies.

 

If the truck in question is the model year 2001 Ram in the original post, you need to be aware of this thread (on that "other website") regarding 2001 warranties.

-Thomas