pour some INJECTION Cleaner in the Gas Tank!!

    My 1989 S-15 Jimmy 4.3V6/Automatic (aka The Blazer) did that after the
body was put on the 4x4 chassis (started life as a RWD 4.3 truck ).
Didn't do it before the smashed 4x4 body was removed.

    What I found is the vaccume line from the termial switch in the air
cleaner housing, had cracked. In more then one location. I found some
rubberized repair line. Which after cutting out the bad sections, I
Glued in place. I also found another one of the plastic vaccume lines
was split, while spraying carb cleaner on the repaired area (only do
this on Cold Engines with the air cleaner assembly in place!). I didn't
note it's function. Just cut out a half inch and repaired it.

    This same truck has had the vaccume switch for the front diff replaced.
due to  no-engaugement.

    I also have had to replace the ignition coil, and clean the plug
terminals for the coil. The grey plug had one that was green, with
flaking corrision. Inner coil terminals looked to have had moister
sitting in them. New plug on order.

    You should check your ECM for codes, Using a OBD1 Scan Tool. Not a code
reader, but a scan tool that will give you read outs.  If the TBI
Injectors are reciving a speradic, weak, or partial Signal, Replace the
pick up in the distributor housing. I have replaced a number of these
lately on GM TBI trucks, both V6 & V8.

    You should also check fuel pressure (a good test kit will have a GM TBI
adapter), distributor car & rotor, spark plugs & wires, coil wire. Dirty
& or clogged, or bad injectors are another thing to look for, as well as
leaking TBI gaskets, TPS settings, or faulty TPS.

    You can see if your TBI base gasket & intake manifold gaskets are
leaking using carb cleaner on a COLD engine. Never Attempt on a Hot
Engine. Have a Towel & a Class C or 3 fire Extengiser handy. You can use
a towel to smother flash fires, any thing more then that use the dry
chemical.

heres what I started with.
1989 S-15 Jimmy 2WD 76,000 Miles 4.3 V6, TH700R4, 3.42 bad engine
1989 S-15 Jimmy 4x4 299,000 Miles 4.3 V6 TH700R4, 3.42 gears Hit hard
front, rear &  passengers side.

    Took 2WD body, cut hole in floor for transfercase shifter. Lowered on
to 4x4 frame. Kept ECM, Engine Harness and compleate driveline from 4x4.
Front passengers fender, hood, bumper, core support from a 1991 GMC S-15.

Total miles since body swap 101,and some change.

Charles Bendig