92 3000GT/STEALTH- What do i do now??

The vehicle is a 1992 Dodge Stealth R/T with the 3.0 DOHC-5sp. with 135,000 miles. I'm at my wits end on what to do next to fix my problem. The problem always shows up after driving it for 2-3 miles. It's a miss in the engine. I can tell something is wrong because when i'm doing 30mph and try to hold that speed steady the car has a miss that you can feel.
I have changed the plugs,the wires,fuel filter,02 sensor. This is the second engine because the first one blew. So what I have done up until now is taken parts off the first engine and installed them to troubleshoot to see if that is the problem. I have changed the 3 ignition coils,maf sensor,throttle body,coolant sensor,and have replaced every vacum hose. None of this has helped.
Whatever problem I have it does not set the Check Engine Light. I thought about the timing being off but the guys at the local parts store said the timing can "never" be off on this type of engine. Is that true? By the way I sent the injectors in to be rebuilt and flow tested. My ego is at stake here. I want to figure out the problem myself.
This car is not a daily driver. On another site i'm told it could be a weak fuel pump. In all of my years driving cars i never had a weak pump,it just broke. Is it possible for the pump to be weak and i'm not getting the proper amount of fuel? I always thought either a pump worked or it didn't. If I have to I will just give up and have to take it to a mechanic.
What bothers me about that is will they figure the problem out? The truth is I wished it would just stop running and that way I could probably figure it out. Can you give me some advice? I do thank you for the time. John

I thought about the timing being off but the guys at the local parts store said the timing can "never" be off on this type of engine.

This is why they work at a parts store for $8 an hour and don't actually work on engines. Definantly check your timing. If you check out the FAQ, there are links for the 60k tuneup. Click on them, and in there it shows how to properly line up the timing belt via the hash marks. I'd start there.

Also, you said your check engine light isn't coming on. Perhaps the bulb is burned out. Might wanna try pulling your codes just in case.

http://www.stealth316.com/2-diagcodes91-93.htm

Double check you have the right pin for the ground

http://www.stealth316.com/2-diagconn.htm

Thanks for the advice! "Thats why there working for $8 an hour". I never thought of it that way! Again,Thanks. John

Well they were kind of right, the ignition timing cant be off on a 93-99 DOHC, but the valve timing certainly can. And on a 91-92 the ignition timing was adjustable too.........

I hope you get your 3S running smoothly again. I know its a pain in the ass when you can't find what's wrong..

yeah and don't pay much attention to those guys working at the parts store..this past saturday I had one guy (unfortunantly I knew him in highschool) tell me that my car was an SOHC and there was no way to do a TT swap and that the twin turbo model was called a VR6 not a VR4 and it was only RWD..then I asked him what he drove and he pointed to a focus (red zx3 focus with mismatched body kit, svt wheels, racing decals, fart can, huge wing, glued on hood scoops and roof scoops) so I told him so you're a ricer boy huh? and he goes nope its got some mods and when I asked him what? he said cold air intake and paused which I though was for dramatic effect but turned out that was it....


sorry had to vent...but good luck with your ride