Probably been covered before

[frog13]

2010 Yaris hatchback , 100,000 miles , automatic transmission.
Issue #1 : Not all the time ,but when I stop at stop lights / signs , the engine shakes as if it's going too stall out. Out on the road it's fine. I'm going to clean the MAF sensor. The battery is 18 months old.
Issue #2 : Speaking of the battery. Over the last several months I've noticed acidic buildup on the positive terminal / post etc. I've used baking soda and water to clean away the crud. BUT , I can't get the positive terminal / clamp to come off of the post. I've loosened the clamp nut and the other fasteners at the rear of the post but it won't budge! , what the heck?. I'm not a noob per se regarding general maintenance. If I place any more muscle on this clamp I'm concerned I'll break something. And yes , the negative clamp has been removed from its post. TIA.

[tmontague]

I'd let some on blaster soak in it for a while, spray every 15 mins and let gravity pull it down into the seized point.

Keep in mind the 1nz idles low and tends to have a rough idle from time to time, especially when a high auxiliary load is placed on the engine. Clean the maf, throttle body and use a scanner to check fuel trims during idle and at 3k rpm to check for vacuum leaks. And lastly, cleaning the battery can help

[frog13]

Thank you for the reponse.
Understood on all advice on cleaning various items , battery was going to be first item , but...... .
Idle . Understood on low idle , but this engine is shaking as if it's blood sugar is low or its going thru withdraw symptoms : ). I'll soak with blaster and see what happens. Thanks again.

[WeeYari]

I don't know the sequence of events that have taken place but keep this in mind. If the battery has been disconnected long enough for the ECU to drain residual charge, the engine will idle rough at extremely low rpm until such point as the ecu has relearned proper trim levels.

Sent from my Elite_5_5_Octa using Tapatalk

[frog13]

Understood. This rough idle condition existed well before the battery was disconnected.

[castles]

Engine mounts? Maybe?

[B.B._07]

If your battery terminal is hopelessly stuck you can try a battery terminal puller. They cost about 15 to 20 dollars and a bunch of companies like Lisle, Gearwrench, and OTC make them.

https://www.amazon.com/OTC-4611-Battery-Terminal-Puller/dp/B000ZIZ32W/ref=sr_1_3?ie=UTF8&qid=1524629489&sr=8-3&keywords=battery+terminal+puller

For the idle issue I would try cleaning the MAF sensor. You can buy the MAF sensor cleaner or just use regular brake cleaner.

[frog13]

Gotcha 07.......thank you

[frog13]

Motor mounts. Highly doubtful, but thanks for chiming in. Appreciated

[frog13]

Dang it.....why's the print so small , what next, my feet gonna get longer.....hahahaha :)