95 Buick 3.1 dead after fuel injector swap


#1

Got a 95 Buick a year and a half ago in exchange for doing a tune-up and tranny rebuild on a 98 ranger.

First year no issues but while driving the exhaust blew out at one of it’s hangers so I replaced everything from the catalytic converter back with new.

Ever since I’ve had engine stuttering issues at low acceleration, slow take off from stopped and crappy fuel economy.

I’ve changed the coils and bought new injectors, the problem is when I installed the injectors the car would not start

Thinking it was the cheap gb manufacturing reman injectors I splurged and bought a more expensive set of ac delco with the same issue.

If I swap the old injectors back in the car runs.

Resetting the ECU doesn’t fix the issue.


#2

Put the old injectors and take apart the new exhaust. Put a vacuum gauge on it a run the engine without the exhaust. Note the reading. One piece at a time, put the exhaust back on. If you put a piece on and the gauge drops more than an inch, that piece is restricted.

Can’t he;p you with the injectors, but if the problem started when you replaced the exhaust, that is where I would start looking for the solution.


#3

stripped the exhaust off and started putting it back on a bit at a time, no difference on the vacuum gauge start to finish.