97 JGC starting problem again

[leosalchemist]

My GC had some starting problem back in April and got help here. It turned out to be corroded battery posts. After I cleaned the posts, it worked very well.

The same problem happened again earlier this week. I cleaned the posts again. And it worked. However, occasionally, the car tried to start, I could hear the engine running, but it kind of lost strength or choked then failed to start. I tried to step on the gas pedal while the key is in the starting position, it didn't always work but helped eventually.

The thing is that I'm worried that it would damage the engine to engage the key in the starting position for a prolonged period of time. I also wonder if stepping on the gas pedal would hurt the engine. I would very much like to fix the problem once for all. Should I go back to the battery or check my starter or something more serious?

Another question is that how you guys clean the battery posts? I just wiped them with some paper towel. Should I go for some chemicals?

Thanks a lot!

[lloydjv]

I usually clean my terminals/posts with a wire brush and a solution of water and baking soda.
Engaging your starter for prolonged periods of time can overheat it and cause damage.
You may want to also check ignition system for proper spark and fuel advance.
Check all your vacuum hoses as well, and make sure your air filter is clean.
Another thing to look at is the throttle body and plate. Remove the intake hose from the t/b and look down inside to make sure there is no excessive carbon build up.
Or maybe it's as simple as worn or mis-gapped spark plugs.

[leosalchemist]

Thanks a lot!
I'll check the easier ones like spark plug and air filter. If I can't fix it, I'll have to go to mechanics. Hope they wouldn't give me a surprise.