1988 Cutlass Ciera Idling problem

[gpurv]

Hi,
I have a 1988 Cutlass Ciera, 3.8L, Auto Trans.
Recently I replaced MAF sensor due to cars idling becoming erratic after coming off the highway and stopping in city traffic.
Now the car idles erratically as soon as I put it into gear.
If I am able to get it going it seems to run great over 30 m.p.h. and higher, but as soon as I let off the gas and the rpms begin to go down, it lopes up and down radically and will stall if I do not put it into neutral and keep pressure on the accelerator and rpms over 2K.
I have checked all vacuum lines that I know of from the manual and they seem to be in good shape.
When I check the computer for error codes it says 34 and my manual says 34 is a MAP sensor, but my car DOES NOT have a map sensor
Any ideas on what to look for.
Will entertain all reasonable suggestions

[Vidneras]

Does it say in your manual what a MAP sensor is?

I've only heard of a MAF sensor, which is what code 34 should point to.

[gpurv]

Originally Posted by Vidneras

Does it say in your manual what a MAP sensor is?

I've only heard of a MAF sensor, which is what code 34 should point to.

In my Haynes manual it says Code 34 is the MAP sensor, (Manifold Absolute Pressure sensor).
Although I now know there is no such animal on this engine.
I had replaced the Mass Airflow Sensor and that is when this problem began.
I have been told that reconditioned MAF sensors are often faulty so I brought it back to the parts store and asked them to test it,(they didn't have my old one I turned in to get my core charge refunded).

Originally my car only had idle problems after driving for a while and then coming to a light or stop and then the idle would become erratic.
Now it is Loping radically after the engine warms up or if I revv it up and take my foot off the pedal.
As the rpms drop it either stalls or lopes form 0 - 1500 RPM for a couple of minutes before finally settling and becoming consistent again.
But as soon as I accelerate again it hesitates, stalls often, (unless I shift it into gear at 2K rpms or higher).
I have changed the fuel filter checked all vacuum lines, replaced EGR valve, and all other sensors I know that do exist on this engine.

It was suggested that I might have a clogged fuel injector, (I did fill my gas tank right after changing the MAF sensor), so I put in some injector cleaner but it has not fixed the problem.
I am about ready to put this car out of my misery.

[Mrbizness1]

As per my 88 olds shop manual code 34 is for the MAF sensor

the code will set if the engine is running and either of the following conditions exist. Below is word for word from the shop manual

Engine running
no MAF sensor signal for 250 Ms.
or
Engine running over 1400rpm
TPS over 2.5 volts

Air flow less then 10 grams per second (low frequency)
above conditions for over 10 seconds


I had a simular problem with an 88 2.8 and it was a sticking EGR valve that was at fault.

[phantom240]

hey since you changed the fuel filter, could you tell me where it is?