arroyojim

hi,
i just got back from an emissions test and i am about 10x above normal! a year ago it passed no problem. since then i have changed the fuel filter at least twice and also recently cleaned the air filter. recently i was having problems with power loss which turned out to be a bad lift pump. wondering if i could have done something wrong installing the new one to cause emissions problems? or if running it (not much, maybe 100 miles tops) with a faulty lift pump may have damaged my injection pump (boy i hope not)? also had my belt replaced by some mechanics i'm not so sure i trust. any way a belt change could cause bad emissions?
here are my test results:

"60mph; 57% opacity
50mph: 68%
40mph; 87%

pump seals air fuel adjustment: pass
boost compensation/aneroid: pass
electric engine controls: pass
trap/cat. conv. : pass"

97 2500 5-sp manual
running on biodiesel mostly

any ideas???

thanks!

dodgeman01

I had a problem but after I took out my air filter and got the truck timmed everythign was good.
DM01

arroyojim

could bad timing cause such high emissions? are there other symptoms of bad timing?

CTD NUT

Symptoms of advanced timing are high NOX readings.....typically, the more retarded the timing, the lower the NOX.

arroyojim

thanks,
this test, as far as i can tell, only tests opacity. not sure the relation of NOX to opacity. i know running bio-d causes slighly higher NOX, but this is a major increase in opacity which was not present when i started running bio-d about a year ago. not positive, but i don't think NOX affects opacity?

arroyojim

hey guys,
is it possible that oil is leaking into the fuel through the lift pump?

phox_mulder

Opacity measures the visible smoke.

You might have a boost leak.

Check all intercooler boots for tightness and lack of holes or tears.


phox

infidel

Usually it's the other way round, fuel gets in the oil. You could have a bad turbo seal allowing oil into the intake. Easiest way to check is to remove the boot to the air horn on the driver's side and see if it's coated with oil.

My bet is that your timing has slipped though.

arroyojim

thanks everyone for the feedback. i've looked over the air-intake system and can't find any leaks or loose connections. it was mentioned a few times that my timing may be off. i'm wondering if there is a definitive way of testing for this, and if not, are there other things i can check? basically from what i've heard i have either overfueling, not enough air flow, or my timing is off. just not sure how to figure out which it is. other than the smoke, it seems to be running fine.
(btw, my filters are all clean, and i just replaced my lift pump and pre-filter screen)

arroyojim

forgot to mention:
'97 2500 5-sp; stock as far as i know except for high flow (afe - i think) air filter and some big tires

Dr. Evil

There are some additives that are supposed to dramatically reduce emmissions:

http://www.maryngroup.com/Product_In...Up/Gen_49D.htm

Click on the technical data

newriverSpecon

Another possibility is the test equpiment. If a vehicle prior to yours coated the light or detector it would not matter how much yours is putting out. One of our customers took his through and showed 115% opacity as an absolute number, not a comparison. He drove around and went to another lane and paseed at 6%.

If it was outting out 60% you would have a huge cloud behind you going down the road. How much does it smoke? How about when you mash it at 40 MPH?

Randy

arroyojim

i have definately noticed more smoke after putting the new lift pump in, but i wouldn't say that i have a huge cloud behind me. i don't generally stomp on the peddle as i am usually trying to be conscientious about milage and pollution, not to mention i'm paying over $3/g for b100. i can say that there is a significant amount of smoke when the throttle is in, and also the testing place i go to services only diesels, so i assume (hope) they know about the problems you mentioned, but i will take it out again and see what happens at various speeds and throttle. btw, do i need to worry about damaging things by driving it w/o knowing what's causing the excess smoke?

Dr. Evil

Jim, I would check your intercooler boots for a leak or tear.

No, you wont hurt anything by driving it smoking.

arroyojim

yup, checked them out, and looked over the rest of the intake sytem and couldn't see or hear anything resembling a leak or tear. anyone have any experience with this problem:

"Avoid running your engine for long periods in idle mode (greater than 20-30 minutes). Under idling conditions, low pressures are generated in the turbocharger which can cause oil mist to leak past seals into the two end housings. Although no real harm is done to the turbocharger, as load is applied temperatures increase and the oil will start to burn off and cause blue smoke emission problems."

i don't think this is my problem though b/c i had just done a long highway drive up and down the mountains, about 12 or more hours drive time, so i figure if i had any oil in there it would have burned up by now. so i'm still stumped.

would a plugged up cat cause smoke?