More issue.
 

When it rains it pours. Driving yesterday, the car decided it doesnt want to accelerate anymore. The engine cut out and dropped to 1500 rpm, and the more i pushed the gas pedal, the more the engine didnt respond. Coast to a stop and put it in park, rev the engine to 7000, after that put it back in gear and it was ok. It did it again on the way home that evenging when trying to accelerate getting on the interstate.

As some backstory, i had to replace my heater core hoses 3 weeks ago, took the air intake plenum off to get to them, and since then the car doesnt want to idle down. Its not that abnormal in drive, it idles around 800 rpm, but in park its idling around 1200. I do not know if that has a connection, but its all i have right now.

I had similar problem w/ my 94EX which had a sticking fuel pump. It would mysteriously die (oil. Alt, Check Engine come on) and coast to a stop. I initially thought Main Fuel Relay, however a tell-tale light hooked to fuel pump showed power to fuel pump and no fuel pump action.

Suggest stopping and listening for fuel pump to come on when keyswitch is turned to On, run 2-3 secs, and go off. If you don't hear fuel pump, either Main Fuel Relay or Fuel Pump are likely faults. Diagnostics (as above) necessary to isolate problem.

Your problem is slightly different if I understood and engine never completely quit? This might point to a fuel delivery issue; restricted fuel filter, weak fuel pump, corroded fuel pump wiring connections (low voltage to pump).

good luck

the fuel filter is less than 6 months old, so I hope that isn't it. yeah it never totally dies, I don't have a CEL code, it just doesn't accelerate. the fuel pump is about the only major component I have not replaced on this old bird, aside from the transmission.

addition: I tried resetting the ECM and same result on the way to work today. it only seems to do it once for about a minute or so then never does it again while I'm driving.

Elevated idle suggests an air intake leak. Suggest checking for a significant air intake leak; PCV hose problem, brake booster vacuum source.

good luck

would that be a contributor to the driving issue?

Yes. Check for vacuum leaks and or a crossed vacuum line. It is well within theory that when you removed the air intake and were working on the heater core that a dry rotted vacuum line was bumped and is now cracked. Check all lines including the EGR vacuum lines which run along the fire wall. Also check the engine temp. sensor wiring as that is located just below the throttle body air intake.

will do. I know the wiring for the temp. sensor is good. I had to replace that plug not too far back.

ok. replaced the plenum gasket, cleaned the valves and the inside of the TB while I had it off. It fixed the idle issue, but the random bogging down while I'm driving still remains. I didn't find any bad vacuum lines. however this one sensor on the firewall that has what looks like 2 vacuum lines running out of it. one seems to not have a place to go.

Engine Mount Solenoid valve is on firewall. One vac supply line to intake manifold and other vac line goes to rear motor mount vacuum actuated valve.

good luck