Need Help with Code Meanings

[jfarr]

My '92 (original owner) bucks and stalls intermittently, then takes 20 minutes or so before it will restart. I suspected the wires or plugs and replaced both - no change. Then I figured the Crank Position Sensor (CPS) was shot so I did the full 60K (timing belt, water pump, CPS and front seal) with no visible leakage from the old pump - still no change.

So I bought a code scanner (since the car won't make it to the nearest garage) and got the following readings:

KOEO - 551 Idle Air Control / Solenoid (IAS) - circuit failure

Continuous - 172 Heated Exhaust Gas Oxygen (HEGO) sensor - indicates "lean" (Bank #1) and, 211 Profile Ignition Pick-Up (PIP) sensor - circuit failure.

Does anyone have any insight on what I do next???

Thanks,
300K and holding...

 

[sdpatt]

The 551 is not the idle air control valve, but instead the ntakemanifold runner control (IMRC) solenoid that opens the secondary intake runners at 3,950 rpm. Make sure the electrical connector is attached to the solenoid on the center of the rear intake plenum near the firewall.

The misfire would indicate plugs and wires to me too. What plugs and wires did you install?

Since only the back cylinder bank O2 sensor is reading lean, the chances are that the O2 sensor is old an needs to be replaced. Change the front one too, since they should be replaced at the same interval as the spark plugs: 60,000 miles.

There is a chance that you do have a vacuum leak on that rear bank. Check for any loose vacuum hoses or exposed vacuum ports.

The 211 refers to the crankshaft position sensor (CPS). Since you replaced this sensor recently, I must ask if you gapped it to .03" (.76mm). There is a chance that this memory code is left over from the old sensor if you never reset the EEC memeory codes (remove the test jumper while the codes are flashing on the CHECK ENGINE light).

Check the tightness and condition of the electrical connectors on the DIS module on the intake manifold's passenger side balance tube. These connections should be tight and free of corrosion. A poor connection there could show up as a CPS or CID sensor fault. Try wiggling the connectors while the engine is running to check for a poor connection.

You didn't need a code scanner to rear the codes; only a short jumper wire and the ignition key. See the link in my signature for the simple set-up if you are curious.