Sorry about the extensive vehicle history to explain my question. My area of Colorado requires lug-down opacity testing of the exhaust prior to vehicle licensing. My vehicle is driven approximately 5000 miles yearly and has passed emissions with 20 to 25% opacity over the last few years. 35% is the cutoff. This year, the vehicle failed with 60%. Nothing else has changed internally with my engine over these years. I allowed the shop that did the dynamometer testing to proceed with additional repairs. They replaced all the injectors with supposedly pop tested rebuilds. The fuel filter and air filter were replaced and a retest was performed which yielded a 61% opacity. At this time, I was going to proceed with a waiver of the emissions testing that is allowed because of total dollar repairs spent. Out of curiosity, I turned the fuel pump down two flats and had an emissions retest performed. The result opacity was a passing11%, but expectedly, power was down significantly. I was able to go ahead and license vehicle with these results.
My question is:
Does a worn injection pump produce more or less fuel flow into the injectors? Am I correct in assuming that this flow would generally be at a lower pressure? Thirdly, if the smoke cleared up significantly following fuel adjustment, does this give me any idea as to the status of the pump internally?
FYI, the pump has approximately 30,000 miles on it since a quality rebuild was performed.
Thanks for any replies!
My question is:
Does a worn injection pump produce more or less fuel flow into the injectors? Am I correct in assuming that this flow would generally be at a lower pressure? Thirdly, if the smoke cleared up significantly following fuel adjustment, does this give me any idea as to the status of the pump internally?
FYI, the pump has approximately 30,000 miles on it since a quality rebuild was performed.
Thanks for any replies!