What causes these codes?

34 is a MAF code if Im correct, and 32 is a baro(MAP) sensor

The car starts right up but them the idle surges some...if the MAF is disconnected the idle is smooth.

The check engine light comes on only when crusing on the freeway...usually disappears at the first stop sign. BTW, using a paper clip to ground the ALDL to show the codes with the blinking check engine light.

Besides a bad MAF or MAP sensor, what can cause these codes? With the air filters removed the idle is smooth just like when the MAF is disconnected. When replaced the idle surges again.

Any ideas/opinions would be appreciated, TIA

 

85,

Welcome to ThirdGen.org!

Since you have a MAF sensor to disconnect, I'll presume you have a TPI engine. That being the case, the '32' would be for an EGR problem, not a BARO sensor.

The '85 was an unusual year for the TPI system. It was the only model year to use a MAF interface module piggybacked to the ECM. This module provides power to the ECM, controls the burn-off function, and converts the digital MAF signal output to an analog signal that the ECM can use. The DTC '34' could be a problem with any of those functions, or it could be the result of failure or misadjustment of another engine sensor.

The DTC '32' indicates a problem with the EGR system. The EGR is controlled by the ECM, and should only be active when driving at light to moderate throttle loads and at cruising speed over 40 MPH. The "Check Engine" lamp is likely coming on due to the failure of the EGR to operate. That system will certainly need some diagnosis to isolate the problem(s). That doesn't mean you need to visit a shop with specialized equipment, only that you need to spend some "quality time" with the system and a voltmeter.

That problem could be realted to the '34', or not. For the purposes of diagnosis, it is important to verify that the EGR valve is fully closing (not leaking vacuum through the valve) and that it is not opening prematurely.

Before you do any of that, however, you have an obvious problem with your air filters. If simply removing the filter elements will alter the idle speed or quality, it's time for new filter elements. Filters that have become wet will not pass air easily, and will tend to set a '34' (low measured intake air flow). Resolve the air filter element situation first, then see if your other problems continue.

We'll still be here.

 

Sorry I forgot to mention the motor. slipped my mind

It is a 2.8 multi-port

Air filters are going in later today, the book I have shows code 32 as being a BARO sensor, but I cant find a BARO sensor anywhere. Along with the air filters, Im going to go with regualr tune-up parts as well, new wires,cap,rotor,air filters and the such...after that I will look into the EGR.

Still not sure why when i disconnect the MAF I get a smooth idle (with the dirty air filters in) when the air filters are out, I get a smooth idle no matter if the MAF is connected or disconnected.

Thanks for the advice and I will start a more thourgh diagnostics tomorrow when I have more time.

 

As Vader pointed out, you do not have a Baro sensor with a TPI / Multiport engine.

 

If the car runs better with the maf disconnected then it could very well be that your maf is in need of replacement.