More on the plenum kit install....

Previously (May 2nd) I posted:

---Ok, the verdict is in....no increase in fuel economy was seen.

---One tip I recommend is to go ahead and have some replacement

---o-rings for the injectors in case any of them are dried out like mine

---were....one even broke when removed. Beyond that, I still feel

---as though there was a slight increase in performance and wish I

---had done this mod years ago.

---2001 QC 2500 4x4

After several weeks and more miles, I can now say that yes indeed, I have experienced an increase in mileage...a little over 10% in fact. BEfore installing the kit and thermostat I was getting between 10.2 and 10.5 mpg in the city. Now I am getting 11.5 minimum. Could this be because any residue was effecting proper operation of the exhaust sensor? And once that residue was burnt off and the ECU was getting the proper info the ratio leaned out? Beyond that, an obvious increase in power and a cooler running temp are the only things I seem to have noticed.

Translated into dollars, I expect to see a $400-500 savings per year making the money and time spent to install seem trivial. Again, I highly recommend anyone that has not done this yet...to do it asap.

Reply to
Carolina Watercraft Works
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Laz, do you folks get winter gas? One or two mpg increase usually happens when they switch to summer gas.

Roy

Reply to
Roy

Not here...usually the same throughout the year.

Reply to
Carolina Watercraft Works

Next will be to see if the Zmax treatment increases the mileage as it did before....more to come on that.

Reply to
Carolina Watercraft Works

Next will be to see if the Zmax treatment increases the mileage as it did before....more to come on that.

Reply to
Carolina Watercraft Works

Would this also apply to a 1997 5.2L Dakota? (I couldn't find your original post).

Reply to
Electrician

Not sure which years were effected but the 318 does have the same problem. Does your motor act as the 360s do with the leak?

Reply to
Carolina Watercraft Works

The only problem I've had is that it started using oil all of a sudden, about

1 quart per 3,000 miles. The consensus here was that it probably was the plenum gasket.
Reply to
Electrician

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