1998 Other GMC Models runs rough, idles high, not alot of po

1998 GMC
120,000 MILES • V8 • 4WD • AUTOMATIC
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MTWILDER
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  • 1 POST
Where to start. I've recently rebuilt transmission and prior to doing so I had a major oil leak and the radiator stays at only 3/4 compacity. Whil
e tranny was out these are all the items I had replaced.
1. Right side plugs were fouled. Replaced all 8
2. Coil
3. The sensor mounted at the coil
4. Distributor cap, rotor and plug wires
5. Oil pan gasket
6. Doughnuts at headers
That's all concerning the engine. Double checked firing order all plugs are as they should be. I'm still loosing motor oil but can not find where. Occasionally a small amount of smoke is present out the passenger side exhaust. I'm afraid I may have either a blown head gasket or cracked something. What would you suggest I do to trouble shoot this problem?
Thank you for your attention.
Jun 17, 2010 at 2:30 AM
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RASMATAZ
  • ASE Certified Mechanic
  • 75,992 POSTS
  • ASE Certified Mechanic
Start by checking engine compression to determine its condition its useless to replace parts if the compression is no good that will fouled-up the plugs
Jun 17, 2010 at 3:19 AM
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