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Been having some issues with idle ive never had before. Fixed my ghetto y pipe in case of boost/vacuum leak nothing. Boost gauge reads good vacuum and 5-10 pounds of boost regularly(still havent figured that out).

Its weird cause the care runs good when driving no problem but when im at idle its been getting really low below 500 rpms. The car has 169,XXX on it so its got a few on her. Timing belt was done at 86,XXX its time, just havent had the money.

What if any are some signs my timing belt is about to shit out? maybe worse head gasket? Im not sure what the deal is, and it seems to be affected my electrical load as well, even after a new battery(optima red top).

If i shut all the electrical stuff off ie lights radio defog the rpms are fine but put it all back on bogs down then back up. is this making any sense? Anyway does the same thing after driving comes to a stop and super low idle doesnt make sense. Any input would be awesome.

Checked the alternator output when you've got lots of accessories on and off?
Cleaned the IAC?
What vacuum you read while idle?

vacuum at idle is like 18-20 psi. is that normal? its whats its always been sense i did the TD04 TMIC and all that jazz. Ive never cleaned the IAC, seems to me things can go worse if you do.

Yes, thats a normalish vacuum range.

ya then i have no idea whats wrong.

so i went and got a new battery and had the alternator tested, still good after almost 20 years. still having idle problems again i have not cleaned the IAC still a little weary about it. throws no codes and seems to bog down when im at idle and i turn the lights on or step on the brake pedal.

please any input or experience would be greatly appreciated

I'm assuming you had an auto parts store test the battery & alternator in the car? If so, sometimes they may show ok, but if you remove them from the car to be tested, they test bad.

If you have another vehicle, I'd suggest bringing both in to be tested outside of the car.

Also, if you have a volt meter, check the voltage at the ECU and see what your voltage drop is across the relays & switches to the ECU from the battery.

Also, you may want to check your grounds, especially the engine ground located on the back driver's side of the intake manifold.

i was thinking grounds was the problem cause an electrical load shouldnt cause such and idle drop.