Difficult Cruise Issue

[nek]

Hey guys,
My car is acting up again as usual and now its keeping me from work. Initially when it warmed up to a certain temperature, it would start jerking (fluctuating between accel and decel) when I was cruising at ~2200 rpm constant throttle.
Now it seems like when I start it up, it just starts doing it right away.
Under constant throttle,
afr goes lean,
rpm jerk around
and for some reason my coolant gauge will show overheating under throttle then jump back down right when I lift off even though my ecm link is showing normal temperatures. Its hard for me to finger point this so i am just trying to throw things out there to see it rings a bell. (no its not fuel cut)

Also, It started today about 15 miles from home, while I was on the highway at 60 mph low rpms, the throttle just cut out completely, I couldnt accelerate I could only coast..... turned it off and turned it back on, now I could accelerate again
Anyways here is a video,
Dsm cruise issue - YouTube

And some logs below, first (short one) is idle second is starting up and cruising around trying to catch the problem. Notice at the end, in park at constant throttle how the afr is just jumping around and going lean.

On a side note, when your car is powered on without the engine running, does the brake / at temp/ and battery light come on? I know if they come on while running it means you could have a bad alt but what if the engine is off?

 

[94allwheeldsm]

You might have a bad coolent sensor telling your ECU that it is over heating, does it randomly shut off? It could also be your maf.

 

[big_d]

I would first suspect a maf sensor issue... At 466ish seconds into the first datalog, you can see the MAFraw signal start to become erratic which may be causing your AFRs to do what you're experiencing. Any reason you went with a GM maf when the 2g maf sensor is perfectly competent?

 

[nek]

I went with the GM maf because it came with my ecmlink setup. Also I wanted the blow through setup. I tried my friends maf as well but the issue still occurs.
The coolant sensor that feeds the gauge is not the same one that feeds the ecu. The gauge sensor is after the radiator and the ecu sensor is prior to the radiator.

Last night I took a look at some of the sensors and when looking at the cas (95 style) the cranking voltage (still on the cam) the voltage reads just fine but the idle voltage is between 2.3 - 2.7. I read online that it should be between .5-2.0v but I also read that the 95-96 cam is inverted so I dont know if this is right or wrong.

I also tried locking the cpu in open loop mode to see if the issue still occurs. It does.... Which sensors can I roll out? I was under the impression that the ecu doesnt use a few of the sensors while in open loop, anyone know which?

Here is a list of things I think it could be.....
Cas/ CPS/ fuel pump/ ecu / grounding issue/ possibly alternator/ coil pack?

Things I dont think it is...
maf/ tps / boost leak/ plugs/ wires/ fuel filter probably not isc.

Again its running lean and jerking while in close and open loop all the time but fine while idling ...