PontiacBonnevilleClub.com

Hey guys, bought a used engine for my 99 in November. other one locked up. had loaned it to my 78 year old father who had the oil chaged at walmart while he had it. with ut asking me., wll he meant well... wrong oil and it locked up. anyway getting ready to do plugs and wires, have read the threads o what to u, gutting air box and doing tran filter and fluid.any suggestions
or tips. also i am getting 22 to 24 mpg now is that bad?

Is that 22-24 city, highway, or mixed? If it's city, that's great mileage. Highway isn't completely terrible, but pretty low. If it's mixed, and depending on your driving habits, that sounds about right. I usually get around 18-19 around town, and around 30 on the highway. If you have a lead foot though, of course those numbers will be lower. How many miles are on the car/new engine? How are the O2 sensors?

From our very own Ed (00beast)

00Beast wrote:

• 1987-2005 Bonneville / Buick 3800 Maintenance List
  
  Grease: Ball Joints, Tie Rods Every 8-10k ( Green Grease or Amsoil Grease recommended)
  Air Filter Every 15k (Amsoil EaA, Purolator PureONE)
  PCV Valve Every 30k
  MAF Sensor Element Cleaning/TB Cleaning Every 50k viewtopic.php?f=48&t=1661
  Fuel Filter Every 15-25k (Purolator, AC Delco, WIX) http://www.pontiacbonnevilleclub.com/fo ... 45&t=23215
  Spark Plugs Every 30-50k (NGK TR55, AC Delco 41-101 or Autolite 605) (Never Bosch)
  Ignition Wires Every 30-50k (Napa Belden, AC Delco, Autolite Pro, NGK) (Never Taylor or Bosch)
  Oil & Filter Every 5-6k or Every 6 months (Valvoline SYNPower, Pennzoil Platinum, or Amsoil )(Mobil1, Purolator PureONE, Amsoil EaO, K&N or WIX) (Never Fram) viewtopic.php?f=45&t=214
  *Conventional Oil Every 3k/3 months(API SM/SN rating) (WIX (Napa), Delco or Purolator filter)
  Tires: Check Inflation Pressure & Visually Inspect Monthly Rotate Every 6-8,000 Miles
  Transmission Flush or Pan Drop Every 15-20k (Always make sure filter is changed when flushed) viewtopic.php?f=45&t=10193
  Cooling System Flush Every 25-50k or 3-5 Years (Peak or Prestone Mixes-With-Any Coolant Only) (Never Dexcool)
  Oxygen Sensor Every 80-100k (30k for non-heated) (AC Delco or Denso) (Absolutely never Bosch) viewtopic.php?f=48&t=794
  Accessory Belt Inspect every 15k, replace every 100k, or as needed
  Cabin Air Filter Inspect and Replace every 15k, or as needed in dusty conditions. (Note: 00+ Only) viewtopic.php?f=45&t=13626
  Evap Core Cleaning Whenever Needed (Note: 99 and older only) viewtopic.php?f=45&t=2432
  Brake Fluid Flush 3yr/50k
  Power Steering Fluid Replacement/Flush Every 100k or 5 years
  
  *Special Considerations*
  All Series II/III 3800's RPO's: L36, L26, L67 & L32, especially important on vehicles factory installed with orange Havoline Dexcool Antifreeze/Coolant: http://www.dex-cool.net/
  Lower Intake Manifold Gasket Replacement, every 80-100k (ignorance of this can allow coolant to enter your engine oil, this happening can cause irreversible lower engine damage, requiring replacement of subject engine)
  
  Series II, Naturally Aspirated, RPO:L36:
  Upper Intake Manifold Plenum Replacement, Every 80-100k (ignorance of this can allow coolant to enter your intake manifold, possible damage to occur can be hydrolock, irreversible damage to emissions devices, misfires, etc. Most times, engine replacement is required if ignored long enough.) viewtopic.php?f=53&t=1061
  
  Series I, II, III RPO Code L67 & L32:
  Change Supercharger Oil; Every 30-50k. (Intense Racing or GM Dealer) viewtopic.php?f=56&t=1690
  Supercharger Belt; Inspect Every 15k, Replace Every 100k or as needed.

1/25/2013 by 00Beast

I would recommend things to do now (if the motor came from a junkyard) to use a MAF sensor cleaner to clean out the throttle body (use a soft bristled hobby paint brush on the sensor itself) and change the LIM gaskets (unless they are metal framed gaskets, which won't have the problem) and put a new UIM on. Then run a can of seafoam or your preferred fuel injector cleaner through the next fillup.