96 buick lesabre ...already posted a question,,but wanted to add that it seems like an air leak,,replaced aic valve,,no change,,the rpms raise to over 3000 and lowers to 800 on and off till car stals,,when driving,,as soon as i take my foot off gas ,,it stalls,,always starts back up and rpms go to over 3000 and fluctuates ,,then stalls

Check for a vacuum leak. You may need to adjust the IAC(idle air control). If the power brakes are also very hard then its a vacuum leak.

check vacuum hoses, pcv valve etc. it seem this is not electrical related, it is more of air exchange if my term is correct, example is the hose from engine to air filter and so on check everything cuts,kinks, rubber tend to crack at age, or when soaked in oil this sort of thing.

two things from what I read is the tps sensor and iac valve

Yes iac valve or throttle control valve. Check for vacume leaks first.

I would suspect the MAF sensor is defective. It is one part that will not set a fault code when it goes bad.

computer needs to be program ...

would change top hose plus make sure there is a thermostat fitted

Remove PCV valve from rocker cover. Run engine at i
dle. Place thumb over open end of PCV valve to
check for vacuum. If there is no vacuum at valve, c
heck for obstruction in manifold port, hoses or PCV
valve. Repair or replace as necessary.

Turn engine off. Remove PCV valve. Shake valve and
listen for rattle of check valve inside. If a clear
rattle is not heard, replace PCV valve.

Visually inspect valve for varnish or deposits whic
h may make PCV valve operation sticky, restricted o
r
cause incomplete seating of valve. Replace if neces
sary. An engine must be sealed for the PCV system t
o
function as designed. If leakage, sludging or dilut
ion of oil is noted AND the PCV system is functioni
ng
properly, check engine for cause and repair as requ
ired to insure PCV system will continue to function
properly. An engine operating without any crankcase
ventilation can be damaged so it is important to
replace PCV valve and air cleaner breather at regul
ar intervals (at least every 30,000 miles). Check a
ll hoses
and clamps for failure or deterioration.

flash is misfire than steady is fault code misfire can be from anything from air cleaner clogged to mass air flow sensor to pcv valve,vacuum leak etc u already changed egr need to have scanned for more specific code code number breaks down to emissions mechanical and or manufactures specific code

Because the car has adaptive technology, it may take a while to reset and adjust to the new, cleaner and better conditions than those to which it had previously adapted.

Did you change the cap and rotor? if the plugs needed replacement, likely they do too

Possible other causes include:

loose or corroded connections to any electrical component you disturbed (make a checklist and tick them all off as you check them);

mis-reinstallation of any F.I. part disturbed(checklist again)

obstructed water flow through the AIC valve;

improper voltage output from the AIC valve (for LH 2.4 systems, should output 8 volt at idle, dropping as load increases; for LH 2.4.2 system output 7 volt at idle etc; testing between terminals)33 and 17 at disconnected LH connector;

possible problem with MAF.

Hope this helps

Saabreur