98 se v6 3.0 ohv stalls under load

hey guys i need some help, the car idles fine even with even all electrical and a/c on. the car will die when put in gear cold but will hold when put in gear warm or hot though it will surge and almost die holding near 500 or so rpms... i have replaced alot of things trying to find the culprit as well as giving it a full tune up and they are as follows...

IAC idle air speed control valve
EGR solenoid
EGR module (silver rectangle box next to it)
new plugs
fuel filter
Coolant temp sender
Coolant temp sensor

what else could this be that affects the motor only under load, the idle in park or neutral is rock solid and doesnt hesitate or anything, thanks in advance

Check for leaky vaccum lines.

well im deaf in one ear and 75% deaf in the other so i cannot hear any vaccum leaks over the noise of the motor because they are so high pitched.... i could try carb cleaner but its still hard for me to hear the motor surge if i find a leak, so aggravating sometimes heh.....

one thing though my pcv valve was completely out one day i think was resulting in part of my problem i pushed it back in but it seems really loose though its sitting in place fine... if that grommet to the valve cover holding the pcv valve is letting air in around the valve would that be substaintial enough to kill it under load? i might try to find some silicon and gush it around it for safe measures but no car its hard to find rides to buy it heh, thanks for the reply and others are welcome

A while back someone suggested using corn starch or talcum powder (I don't remember which) to coat the vacuum hoses, then start the engine. A vacuum leak will suck up the powder leaving a visual indication of where the leak is. This is not flammable and supposedly won't harm the engine. I have not tried this method personally, but it sounds like a good option for your situation.

You may want to search this forum for those options and see which powder it is. :)

-Rod

ok new data... i got in the car and reved it up in park to see how the motor ran at higher rpms trying to figure out if it was a stuck open secondary IMRC plate in the intake... at 4k rpms the motor bucks and shakes and will not let me go past 4k rpms with the pedal to the floor... apparently this is ignition fuel or air breakup... any ideas on why it just cuts out at 4k

i know its not the rev limiter because ive good and well reved it up by mistake to 5.5k rpms in park before and almost 6k in N due to a bad idle air control solenoid

Your car should have a rev limiter for 4k (search the forum and you'll see many others have experienced this as well). If you were able to rev past that before, you must have other problems. Maybe you have a camshaft position sensor issue?

I would suggest you not focus all your effort on the 4k rev limit in park and continue to check into vacuum leaks for now.

-Rod

Agree with Rod.

ok guess i remember wrong, ill keep looking for a vac leak, i have a mech coming by tomm that a friend called so maybe he can find it... would a bad torque converter or a torque converter problem give me all these symptoms... keep in mind when i did get it in drive under its power and took it down the road it drove just like normal no shifting hard or anything

If you had a faulty torque converter clutch (TCC) or TCC solenoid, I would expect the problem to show up after the engine was up to temperature. The TCC should not lock until after the transmission fluid reaches temperature, and I would not expect it to start working fine once it reached that temperature.

Of course if your tranny fluid and filter have not been changed recently, it may be worth performing that routine maintenance item anyway.

I don't recall reading that torque converter failures are common on this transmission, but TCC solenoid failures are not unheard of.

Good luck!

-Rod

well guys i figured id update this thread since nobody else seems too and i noticed alot of people have these symptoms. i took it to a tranny shop as i thought the solenoid was the culprit. the shop cleared out all the codes that triggered from me unplugging the tranny harness and tested it all out. they found no problems with the car. the only code that came back a few times was something about the upstream and downstream sensors swapped. i have no idea what this means as i havent touched either of the two. they looked at the sensors and said nothing looks out of ordinary, they suggested maybe there was a short or perhaps the wires crossed and fused together somewhere in the harness. the car drives just like normal now so im going to drive it as is until the problem returns. im happy as i have my car back for the most part and it only cost me about 50$ for the diagnostic. good luck with those with these types of problems.

stan