83 2.8l ?'s
alhandy
08-30-2004, 09:44 AM
I have '83 4x4 with the 2.8l First off it acts like it is getting vaporlock, but the tank is breathing fine. After looking at the motor I noticed the temp sending unit, oil pressure sending unit, and smog pump are disconected. There is also a black ground wire (near oil pressure unit) and lightgreen wire (on pass. sidefront near intake) just hanging loose. Can the emmisions stuff be my prob or the sending units? Also the oil pressure wire is broken (the one I think is oil pressure anyway, could someone tell me what color it is?). Can I remove the Emission control gear safely? :eek7: I don't need it if it can be removed without messing up the engine too much.
busa_4
08-31-2004, 01:36 PM
The Computer Is Programmed To Run At Cold Startup With The Smog Pump On To Heat Up The O2 Sensors Quicker Giving You Closed Loop Quicker Which Will Give You Better Gas Mileage. If This Is A Everyday Street Vehicle I Suggest You Repair All The Wires And Connect Everything That Is Disconnected. Good Luck
alhandy
09-13-2004, 12:42 PM
I looked around the truck It doesn't have a computer that I can find. The '91 I got the bed off had one, but not mine. Unfortunatly I had no motor otherwise I would have compared wiring.
Cant_Handle_It
09-13-2004, 02:59 PM
i saw something under the glove box idono if thats a computer but you can check
sector95
09-27-2004, 09:10 PM
I have '83 4x4 with the 2.8l First off it acts like it is getting vaporlock, but the tank is breathing fine. After looking at the motor I noticed the temp sending unit, oil pressure sending unit, and smog pump are disconected. There is also a black ground wire (near oil pressure unit) and lightgreen wire (on pass. sidefront near intake) just hanging loose. Can the emmisions stuff be my prob or the sending units? Also the oil pressure wire is broken (the one I think is oil pressure anyway, could someone tell me what color it is?). Can I remove the Emission control gear safely? :eek7: I don't need it if it can be removed without messing up the engine too much.
First off, the '83 trucks had no computer. I would strongly suggest getting a Haynes or similar manual that has wiring diagrams to assist in reconnecting your loose wires. An easy way to find out whats working as far as warning indicators is to turn the ignition on (don't start the engine, just turn the key to the "on" position). If you have idiot lights they should all test good (light up) if everythings okay. Those that don't either have a bad bulb, a bad sensor or are not connected. If you have gages then they should all power up when the ignition is on.
Emissions equipment can be a problem if they have been rendered inoperative. There is no computer on this engine and all emissions, engine timing, and even the auto trans OD are controlled by tempurature sensitive vacuum valves; there is no input from any engine sensors. Engine vacuum is what operates the various emissions gear and functions and if the hoses have been removed there's a good chance you have some major vacuum leaks. I have an '85 S10 with the 2.8L motor and the previous owner had disconnected a bunch of emissions stuff by simply removing the vacuum line(s). In addition, many of rubber vac lines where rotted and leaky. Needless to say this truck ran like garbage when I got it. After restoring, replacing and reconnecting the various hoses and emissions gear the truck ran great (my state requires emissions testing on all vehicles newer that 25 years). Because there is no computer, you can remove the emissions equipment and the engine will run... how well is anyone's guess. If you do remove the emissions gear make sure to plug the vacuum lines. Replace all the vacuum lines, even the ones you plug, as they are probably quite rotty and leak prone.
Your engine is fed its go juice mixture with an evil little device known as the Rochester Varajet II model 2SE carburetor. This little jumble of vacuum breaks and spaghetti linkages will turn the most avid Rubic's Cube maven into a drooling basket case; I know, I rebuilt the one on my truck. There is plenty of opportunity for a rough running engine in this little jewel of a carb given all of its adjustments. The carb sits atop a special gasket/heat shield... if you look at it carefully you'll see a wire lead coming from it; that is the power lead for the Early Fuel Evaporation heater (or something like that). It is a heated grid, located right under the primary bore of the carb, and it helps to fully atomize the fuel vapor as it leaves the carb. If the heater is toast then it can cause some serious driveability problems.
Hope this helps a bit and good luck with your poject.
Mike
First off, the '83 trucks had no computer. I would strongly suggest getting a Haynes or similar manual that has wiring diagrams to assist in reconnecting your loose wires. An easy way to find out whats working as far as warning indicators is to turn the ignition on (don't start the engine, just turn the key to the "on" position). If you have idiot lights they should all test good (light up) if everythings okay. Those that don't either have a bad bulb, a bad sensor or are not connected. If you have gages then they should all power up when the ignition is on.
Emissions equipment can be a problem if they have been rendered inoperative. There is no computer on this engine and all emissions, engine timing, and even the auto trans OD are controlled by tempurature sensitive vacuum valves; there is no input from any engine sensors. Engine vacuum is what operates the various emissions gear and functions and if the hoses have been removed there's a good chance you have some major vacuum leaks. I have an '85 S10 with the 2.8L motor and the previous owner had disconnected a bunch of emissions stuff by simply removing the vacuum line(s). In addition, many of rubber vac lines where rotted and leaky. Needless to say this truck ran like garbage when I got it. After restoring, replacing and reconnecting the various hoses and emissions gear the truck ran great (my state requires emissions testing on all vehicles newer that 25 years). Because there is no computer, you can remove the emissions equipment and the engine will run... how well is anyone's guess. If you do remove the emissions gear make sure to plug the vacuum lines. Replace all the vacuum lines, even the ones you plug, as they are probably quite rotty and leak prone.
Your engine is fed its go juice mixture with an evil little device known as the Rochester Varajet II model 2SE carburetor. This little jumble of vacuum breaks and spaghetti linkages will turn the most avid Rubic's Cube maven into a drooling basket case; I know, I rebuilt the one on my truck. There is plenty of opportunity for a rough running engine in this little jewel of a carb given all of its adjustments. The carb sits atop a special gasket/heat shield... if you look at it carefully you'll see a wire lead coming from it; that is the power lead for the Early Fuel Evaporation heater (or something like that). It is a heated grid, located right under the primary bore of the carb, and it helps to fully atomize the fuel vapor as it leaves the carb. If the heater is toast then it can cause some serious driveability problems.
Hope this helps a bit and good luck with your poject.
Mike
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