Engine "Stumbles" when pressing the brake

[Zeeknof]

I got an 89' fuel injected Festiva. I got it for free and it was already converted over from carb to fuel injection. The engine had a really bad knock so I just grabbed a 76k mile engine and put it in. I had to re-wire the fuel injectors and use the carb'd engine's disty to get it running. I got it idl'ing good but when I press and hold the brake the car wants to stall out. Anyone know how to solve this or what's happening? This is really the only thing from me making this car my daily driver. If it matters the car is an automatic as well. No power steering or anything....no options at all except for defroster for that matter. Any help would be greatly appreciated. Thanks,

Shaun

[FB71]

first, the ecu doesn't like the sawtooth signal the carbed dizzy puts out. get on for an efi car (squarewave).

second, is the car in gear when this happens? Only in park? Doesn't matter/ both?

It could be a bad booster, leaking air into the vacuum line, if it happens anytime the brake is pressed, regardless of trans position.

If it only happens in gear, I would suspect a bad torque converter, dragging at low rpms where it should be free-wheeling.

Does it sound like its running out of fuel, or does it fight to sty running and surge?

[Zeeknof]

I got a spare fuel injected ecu that I will try and switch out this weekend. I am not sure if whoever converted the car from carb to FI switched ecu's. It happens no matter what gear your in. Another thing is when you floor it in gear from a stop it stumbles for a second and then takes off. It seems to be the engine that is having the trouble here, I don't think it's the torque converter when this happens. Is there any way to check my brake booster to see if it's bad?

Shaun

[studdyhalllooser]

Does it sound like its running out of fuel, or does it fight to sty running and surge?

would this be bad injectors?

[FB71]

does it lack power after it stumbles on hard accel, or is it just a breif stumble then normal accel?

to check the booster, remove the vacuum line to it and cap it off, apply the brakes and see if the condition still occurs. If it does, its not the booster. Since its a converted car, it could be an electrical concern.

And I wasn't saying the ecu is bad, I'm saying the signal output by the carbed distibutor isn't correct for the efi ecu, so the ecu doesn't understand it correctly. get the correct distributor.