1995 Chevy S10 Blazer

what transmission, here. automatic or manual stick shift?
S10 not blazer S10

old cars this old (pre digital documents) are hard to find and when found are not complete. or poor .
A/T box?
the PRNDL switch must be good. and cranks in both Park and neutral.
yes the relay clicks too, if not the PRNDL is prime bad part.
there is fuse named CRANK.(1st inline here)
the starter can be hot wired (a test) to prove starter work.
if stick shift TRANNY it is called the clutch switch. to crank,
some books say hood up fire wall, center is relay. IDK


see why we ASK transmission first/
if the relay does not click the fuse crank blown
or PRNDL is dead only on P mode, try N.
if stick shift,, clutch CCP switch bad or just mal-adjusted.
ST below goes to the relay then to starter solenoid
the relay colors are there. Green or Purple.

PRNDL is on side of TANNY part of shift linkage.

It sounds like when you accelerate it downshifts and acts like it is in neutral, when you let off, it shifts back to coast like it is in drive. I would question shift solenoid first. I know this is what 1-2 shift solenoid can act like if you have no low 1 and starts in low 2 or 2nd. There are two solenoids, 1-2nd and 2-3rd. You can drop pan and change them easy.

a number of issues. Tcc regulator bore worn out, the infamous check ball seat it hammered badly, or/and calibration issues. I have seen all three issues on the same trans - often!

You have a problem with your transmission that needs to be adressed my a good trans shop.

HI YOU MAY HAVE A BAD IGNITION SWITCH OR YEST A BAD SHIFT SOLENOID 3-4

theres a shift cable if its floor model,linkage for column model.

check your flywheel or check your gear rate.

Have the transmission governor checked

Look at the transmission control module and the shift solenoids inside the transmission. It's possible you have lost a connection in the harness plug that goes to the transmission.

Solenoids usually set a code that can be checked with a code reader.
Make sure that the oil in your transmission is full and clean...solenoids can get gummed up by varnish if trans is not serviced properly.