Engine issues

Hey everyone
My names Vasili ive owned my mr2 sw20 1991 gen1 for about half a year and cant remember a day when its run well. :(

So whats the problem?
During acceleration if you throttle more than a tiny amount the car jolts violently. The engine cuts out but keeps running because of the momentum i guess. As in red lights come on the dash.

After dealing with this for a while i found at the ecu an hks fuel cut defender installed to a blitz access ecu. I moved the fuel cut defender up the drove it.
Went really well. Then i moved it back to it's orginal spot just to see. And then it still ran really well.

Until a week ago the car would start the die shortly after. Played around with things but nothing worked.

Got it towed to a mechanic he spent hours on it with an explanation that the blitz ecu and fuel cut defender were shorting out causing the issue.

So he replaced it with the orginal ecu i had withthe car.
He drove it told me it ran well.
I got it back after paying 700 for it and having the exact same issue.
Really not happy, tryin to sell the car now but I'd rather fix it up n sell it.
I dont like selling something that i know isn't running at full capacity.

Thanks in advance guys
Any help would be appreciated

Hard to guide you without some more specifics...

have you done the basics in servicing (fuel / oil / air filters, spark plugs (what did the old ones look like), changed your spark plug leads, checked the condition of you distributor), checked / adjusted your TPS and air meter settings, checked your timing, checked your oil colour (no white stuff in it), checked your battery (alternator charging), compression check and leak down test. Best of all check for your error codes from the ECU.

What are the tell tail signs... does it smell like too much fuel?

Sounds like it's possibly leaning out, meaning, check the voltage to the pump (12v at throttle and 9v or below at idle), fuel filter replacement in the engine bay, fuel pump replacement, fuel pump filter in the tank, injectors (get ultrasonic cleaned and flow matched), fuel pressure regulator.

Mine did the same as you mentioned, ended up being the fuel tank fuel pump filter in the tank was blocked. I had to apple cider vinegar clean the tank, as it was crusty badly along the top inside of the tank. Once all cleaned and new filter and pump and it was sorted, but it's a major pain to do - hence was a last thing I did. I have heard of others just using the fuel tank drain plug to drop the fuel (get the grit out) then refilling with clean fuel - but I wanted to do it properly (so I didn't have to do again).