HELP: car sputters and runs rough

ok I have a friend who has a 95 V6 stang. Has a bit over 100K miles and is all stock down to the paper filter and is a 5-speed trans. He’s currently having issues on his car that he cant seem to diagnose. Heres what he sent me over gmail chat:

“cold start is bad. Ill start it and my rpm will drop below 450 then shoot past 1500 for about 2 minutes. Cant bring RPMS past 3500-3800 most of the time. Engine sputters and vibrates whenever i stop at a light. when i press the gas the rpms drop then go up.

put it this way 1st gear can rev up to about 4000 i shift usually around 3000. 2nd gear i can get it up to about the same but it struggles. 3rd gear goes a little higher if im pushing the car hard. 4rth goes to 4500 on the highway when im pushing and fifth i havent gotten that high cuz i dont wanna get pulled over . but i cant get any of them to tach out.”

he replaced his plugs and spark plugs as well as lower mileage EGR since he believed was causing his start-up in the morning as well as idle. I also pointed out that the car’s peak HP is at 4000RPMs, but he told me its around 5500-6000RPMs and he returned this comment:

“the point is that it use to go to 5500 and it doesnt anymore. something isnt right with it and im sure its the timing chain
i know shifting that high is pointless
but my engine is not performing the way it use to trust me i been driving this thing since 04”

now he says also that the car’s making a tingling sound when hes driving around and believe’s his timing chain’s stretched causing the car to sputter and not go past 3500-3800RPMs in 1st, 2nd, or 3rd, but he can shift at 4000 in 4th gear fine and he rarely shifts anywhere near 4000 in 5th gear. So that’s whats going on in a nut shell, any advice and ideas on whats going on is greatly appreciated. Thanks in advance and I’ll let him know what u guys think!

What about the CEL? Has he had it checked for stored codes? Could be a possible clogged cat or 02 sensor or even bad ECT sensor. Fuel filter/ or pump. Could be many things.

And BTW, I hope the air filter isn't stock as in from 95 ! LOL

will he said theres no codes that hes aware of. im chatting with him as u rea this so i'll try to update as much as possible.

will he said this but i dont know if its even possible:
"well that seems like a lot. my check engine light never turns on since the place that i purchased my car from rigged it up that way
fucking bastards"

unless the place he bought it from used a tuner to turn off all or most of the DTCs, i dont understand why in the first place.

When he starts the car does the engine light go on for a moment and then turn off?

i'll have to ask him, brb

So what's going on ?

sorry i was busy at work, he does NOT get a CEL light on startup

He needs to go to Autozone or someplace , they check the codes for free. It sounds like someone has removed the bulb or it burned out. It cant be rigged to not go on. So sounds like they removed it. Just to verify, if he turns the key to the on postion(not starting) the light should be on, along with various other lights like , seatbelt , airbag etc..... . Just look at yours in your car. When you first start it up you'll see the check engine light go on and then shut off.

angus i actually understand what you mean now. i'll have him look and see if the CEL does come on at the turnof the key.