need help!! sputtering

[green75]

help!! my 75 spider is randomly sputtering on accelleration. I am sure it is fuel because tach does not move when the problem happens. I recently put on a new fuel pump, so I think the carb needs adjusted but am not exactly sure what to do. no local mechanics seem to want to help. also, point gap is good and timing is good. can anyone give some step by step advice on adjusting the carb, or know of anyone in the greensburg area who can help. thanks Sean

[mbouse]

more basic than carburetor adjustment would be fuel delivery. you said you recently disturbed the fuel delivery system by replacing the pump. i suspect a clogged fuel filter, or a clogged filter (sock) on the fuel sending unit long before i'd suspect the carb settings falling out of adjustment.

[green75]

I have a new filter to put on this afternoon I will let you know if it helps. thanks

[So Cal Mark]

you may have gotten the wrong fuel pump. there is a recent thread about that by another member. Try the search function

[green75]

I put on a beck/arnley universal electric with a pressure rating of 3.5-5.5. I did have to mount it sideways, not in a 45 degree upward angle like the directions said as it would not fit that way in the trunk. do you think this could be an issue?

[mbouse]

only if the hoses are pinched.

[So Cal Mark]

I'd like a better description of your symptoms. Does it stumble, then accelerate okay? Constant sputter while accelerating?

[green75]

it's tough to describe, but is isn't constant. it will sputter then even out, I think I let off the pedal and it evens out for a while then will start again.sometimes I am not even accellerating just driving along and it will start. kinda sounds like a 2 stroke engine when it's doing it. also the car does have a small put when idling, not exactly mis just a put. I hope this helps, thanks, Sean

[green75]

well got a new fuel pump and new filter today. no change in problem. as soon as it gets warmed up starts sputtering again. not sure where to look now. sending unit? pump relay? float? not sure where to go from here.

[MNspiderman]

Here's a longshot. Your alternator might be dying out and your ignition is running strictly off of the battery. Did you try pulling the positive off of the battery while the engine is running to see if it remains running? If you ever had a dying or dead alternator then you know what i am talking about. when you idle everything is good, then when you give it gas it starts sputtering and getting choppy and you also will see the lights dimming, engine sputters when applying brakes or blinkers, etc. If the engine dies when removing the positive battery post terminal, your problems are solved. just fix the alternator and/or charging system depending on what you have. Please keep us posted.

[velozi]

I had a similar problem that drove me nuts.

Checked the gas pump, fuel lines, carb, ignition....Hours and hours of fun.

It was the $5 ignition condensor.

Good luck.

[fiasco]

I had a similar problem as well, and found the same solution as Velozi - ignition condenser.

I had sputtering at low RPMs and occasional backfire in the exhaust. I got to my diagnosis by first discovering that the sputter was caused by bad spark which wasn't burning all the fuel that was flowing in. Replaced the coil, which didn't help, then the condensers (dual points) which solved the problem.

-- se

[green75]

Finally found it! It was a bad plug. Strange since they were only a few months old. the center electrode was gone on the plug. I hope it's not bouncing around in the engine. Thanks everyone for the help. now I can make it to the grand prix this weekend!

[So Cal Mark]

missing center electrodes can be a symptom of detonation. Check your ign timing