Throttle non-responsive after batter disconnect

OK. Problem solved. When the throttle body as replaced, the air intake hood was not completely attached. Attached it firmly and all codes clear and engine runs perfectly.

wcaswell wrote:
Update #2. Replaced the Throttle Body. The engine now has throttle! Codes cleared. Now getting codes 2195, 2197 which indicate a bad passenger side O2 sensor forward of the Catalytic Converter. Replaced it, cycled the PCM, but still getting those two codes and rough idle and low power. It's drivable. We'll put some miles on it this weekend and see how it goes, then into the shop. Could be a vacuum issue.

Check the PCV line for cracks, that is a typical problem on the Modular engines, plastic gets brittle and breaks.

While you are at it, go ahead and change the driver side front O2 sensor, it is most likely not far behind in failing.

The front or upstream O2 sensors are the ones that the ECU uses to monitor and adjust the fuel mixture and are critical for correct engine operation..

The rear or Downstream O2 sensors are mainly for monitoring the efficiency level of the Cats (IE for emissions purposes) and are not critical.

Update #2. Replaced the Throttle Body. The engine now has throttle! Codes cleared. Now getting codes 2195, 2197 which indicate a bad passenger side O2 sensor forward of the Catalytic Converter. Replaced it, cycled the PCM, but still getting those two codes and rough idle and low power. It's drivable. We'll put some miles on it this weekend and see how it goes, then into the shop. Could be a vacuum issue.

wcaswell wrote:
Here's an update. I bought an Innova Code Hammer OBD2 Tool. It read codes P2112, P2104 and P2111. I disconnected the air intake hoses to access the throttle and cleaned it with Throttle cleaner, giving it a wipe down and manually manipulating the throttle gates to ensure they were not stuck. Then cleared the codes and ran the engine. Codes P2112 and P2104 reappeared and the throttle is still non-responsive. Next step is to replace the throttle body.

Did you try to recalibrate the throttle body to ECM?

Here is a Youtube video of the sequence..

Recalibrate Throttle Body Video

This step will reteach the closed through open values to the ECM..

Barring that, not sure if manually moving the throttle plate was a good idea. The correct way to clean the throttle body is to use the key on but engine not started and then have someone hold the foot feed down to the floor (which opens the throttle plate).

IF your code reader is able to read LIVE DATA, you should be able to read the ECMs TP values from closed to open with key on and engine not running. If TP values change then it just may need the calibration sequence done..

IF you do go with a new throttle body, chances are you WILL need to do the calibration anyways so I would do that BEFORE committing to a new throttle body (remember it WAS working before the battery was removed)..

Is there a resistance test across the throttle body terminals?

A note about Mother Fletcher's Do it Yourself Megawatt Defibrillation -

When I told the cardiologist in Scripps what I did, his mouth kept opening and closing but nothing came out. The RN was also present, and after he exited post haste she quipped "I've never seen him do that before". But the ER doc who did triage visited and said "What you did took some nerve. Were you blacking out?" I replied to the affirmative. He gave me a thumbs up. I went into ventricular flutter the next night and they wheeled in the defibrillator. I took one look and grabbed the big patch that was already on my chest. I guess it scared me so bad I went back into sinus rhythm. The next day came the catheter ablation. The "Code Blue 506" also contributed to my fear.

So!

It is not possible to ISOLATE the memory of an ECU? Oh stupid me, I asssssssssumed the circuits use 5 FIVE Volts instead of 12. Kinda improbable for 5 volts to jump backward through a power supply to the battery cables?

Maybe I am missing something here? Oh pullleease elaborate...

Maybe I should add :) :) :) :)

Here's an update. I bought an Innova Code Hammer OBD2 Tool. It read codes P2112, P2104 and P2111. I disconnected the air intake hoses to access the throttle and cleaned it with Throttle cleaner, giving it a wipe down and manually manipulating the throttle gates to ensure they were not stuck. Then cleared the codes and ran the engine. Codes P2112 and P2104 reappeared and the throttle is still non-responsive. Next step is to replace the throttle body.

MEXICOWANDERER wrote:
The geniuses could design the ECU to employ use a super-cap. If a positive cable should touch negative during a disconnect say adios to the memory backup. A supercap could power the volatiles for how long? Regardless of cause of power failure.

:R

Imagine what would happen with the first "super genius" back yard mechanic that accidentally shorted the battery terminals with a super cap attached to the ECU..



Even IF there was a super cap placed in the ECU, it WOULD have to be designed with at least a blocking diode to prevent heart stopping lightning and thunder from happening in case of accidental shorts..

Not everyone will want to own their own heart defibrillator in their car..

The geniuses could design the ECU to employ use a super-cap. If a positive cable should touch negative during a disconnect say adios to the memory backup. A supercap could power the volatiles for how long? Regardless of cause of power failure.

That "Memory Saver" is still made, You can get one at ______ auto parts (Fill in the blank with your favorite auto parts store.. Even some Department stores may have it in the Auto dept). I had a mechanic leave one in my car once (I returned it to him).

Very handy

On the motor home I have a different way to do it.