cant pull up trouble codes

[daddymac6]

i have a 94 olds 88 and it says its obd1 equiped but the connecter for testing is a 16 pin connecter instead of the 12 pin connecter i have obd2 sconner tool but wont read codes i have check engine light on and car stalls when slowing down to make a stop cant find out how to get codes. any help would be appreciated thank you

[Slade901]

Try bringing your vehicle to Autozone and they can get the code for your car for FREE.

I would suspect the IAC (Idle Air Control solenoid) which is located on top-side of the throttle body intake.

Try removing that IAC and clean it with a throttle body cleaner and a brush. Clean the spot where the IAC goes in to the throttle body intake.

A bad TPS (Throttle Position Sensor) would also cause a problem. Located just below the IAC.
If the gas pedal is not pushed down the TPS should go to the IDLE position and it should produce a minimum voltage to the computer and instructing the computer that it is going at IDLE. If the TPS is malfunctioning, it might give out too low of a voltage and throw off the computer. The TPS can't be cleaned and just need to be replaced.

[michelq]

I suspect the PCM it self

[GMMerlin]

94 was a "bastard" year where GM started its conversion to OBD2 diagnostics.
Most code readers will not read codes on those model vehicles..usually shows and reader error.
I would first pull the code to get an indication what is going on with the PCM and do some diagnostics before replacing any parts

[foggie19]

I have the exact same problem as daddymac6 does in post#1. I got a book on how to pull out trouble codes without a scanner for this car. I have a 19 pin plug with only 5 wires going into it. I tried everything the book says and cant get the light to flash and display the code. Anyone know how to get them? Did you ever find your problem? Thank you

[foggie19]

actaully its an 18 pin plug, OBD1 compliant

[Hansnet]

yep yep I got a 94 as well same deal, my only option is to spend 200+ for a decent scanner then buy the adapter cables or go to the dealer/other shop and they usually charge 30 bucks or so.