I hope someone can help me.

My battery was weak one morning and I might have ruined something by continuing to try and start the car. Anyway I finally had to jump it and replaced the battery. It seems that after that incident I have a hard time accelerating when the car is cold. It idles fine and when it reaches normal operating temperature I don't have the stalling problem. I replaced cap and rotor with no results.

I have an '83 RX-7 with 130K on the motor.
I have Mind Train headers and a plenum chamber on it.

Any assistance would be greatly appreciated.

Thank you!

 

Are you using the choke? (you should) Does it stall WHEN you step on the gas? (accelerator pump on carb.) How long have you had the car and what is your mechanical experience?

 

i thought the choke was only for cold weather

 

Depending on the condition of the motor, using the choke can make starting easier at any temprature. I would guess that Hawaii never really gets "cold", but if the choke stays out when pulled, you can't go wrong by using it. He may/probably have a "real" problem but trying the choke to see if it helps is a good/quick/easy way to learn more info about what's happening.

I was going to wait and see what the answers to my previous questions were but, Are you SURE you have ALL the wires (dist. cap) correct AND that ALL the plugs are firing? I guess we should ask if it the carb is "stock" as well.

 

Thanks for the replies.

I removed the choke a long time ago as Hawaii doesn't get cold enough and the less things I can remove that I don't need the better.

It is a stock Nikki carb with a plenum chamber on it. I did remove the cold start assist also and stream lined the venturis.

I do all mechanical work on the car but hate working on electrical problems. :-)

 

hmm..... i will go with the obvious and say that this may be the problem

 

That's your problem right there. When the motor's cold, it needs the richened mixture to run properly. The only thing you can do is take her easy until the temps come up, but you should be doing that anyways.

 

when I lived in San Diego and purchased a new 1984 SE I was told to always start the engine with the choke, no matter what. I have always done this with my Fb's.
Never thought it was and option to not.

 

as you know the choke covers the primaries on the carb creating a large vaccuum and sucking in extra fuel to make up for fuel that doesnt vaporize due to the low temp. if the weather is cold the car will be extremely difficult to start and if you somehow get it to stay running without the choke the engine will run very lean risking detonation/knocking. now if its warm/hot outside most of the fuel will vaporize so the choke is not needed. until operating temperature some of the fuel remains unvaporized but not enough that the choke is needed. during the summer i never use the choke and my 7 fires up fine and if i wanted to i could start it and fly out of the driveway without problems but i would never do that. i would check to see if you have a spark on all the plugs and make sure all the wires are in the right places like mike said. an ignition problem is a possibility because if your not getting strong spark, the slight lean mixture during warmup could cause misfire and power loss. if you do have spark i would check the coils, etc to make sure nothing is stealing voltage. once you get it fixed, never drive hard until it warms up unless you REALLY have to, your engine will last alot longer this way

 

""when I lived in San Diego and purchased a new 1984 SE I was told to always start the engine with the choke, no matter what. I have always done this with my Fb's.""

Choke on a SE ????

 

yes, i am also confused.... what is this choke you are describing from an SE?

 

Maybe that is a "California" configuration...

 

There is no 'choke' on an SE, 84 or 85. The SE ECU takes information from the RE-EGI dynamic chamber (intake air temperature) and coolant temperature to determine that the engine is cold, and adjusts fuel flow via engine management computer to adjust for cold start conditions.

Also, under the throttle body (SE's have EFI), there is a cold-start assist mechanism that controls the secondary butterfly valves via a 'Thermal-pellet'. This pellet helps to hold the butterfly valves closed until the coolant temperature comes up decreasing airflow to the engine, in conjunction with increased fuel flow from the ECU. Net effect is that you have a higher fuel to air ratio without any manual intervention, vs. a choke in a carbuerated car.

The only thing you need to cold-start an 84SE is to push on the throttle pedal ONCE, remove your foot, and then turn key. Idle and air/fuel are determined by the ECU, not the choke or your foot. When you press the gas pedal ONCE, it resets the cam on the cold-start assist at the throttle body to adjust the buttefly valves.