twocent06

NEED help... (my first stang, ive owned hondas all my life before, im 25 now)bought a 1986 mustang lx/gt late this summer. needed a little work, like paint, springs, struts, shocks, brakes, heater core, and new electrical harness for the lighting. ok no prob, did all that. was running great! also should mention person before me put a 302 engine with an edelbrock 4 barrel carb, and a holley intake. so although in 86 it was fuel injected, mine is not.. i know it has headers, and a msd ignition.. ok, anyways, first day it got cold, started okay, but ran like pure crap. loud popping in gears if rpms were under 1250ish, almost stalling in first gear unless i pretty much road the clutch to keep the rpms higher, then when you got it going, stuttering and bogged down felt like it was holding back so much HP even with the pedal through the floor it would not go.. so got worse and began stalling out if gas wasnt being given at all times. took it to my mechanic, he ended up rebuiling an HEI module and distributer, runs better now, doesnt stall out and idles clean, but still bogged down at lower rpms and popping noise.. so i have a tune up and replace wires and plugs and such.. again slightly better but same problem!.. really would love opinions and solutions to this problem! i really love the car, i have it looking great, its fully repainted, windows tinted now , 17 inch cobra-R wheels, and it is a rare t-top too(in the summer i love). id hate to have to let her go bc i couldnt figure this out!! any clues anyone? beeen researching others info online and forums and i believe some ppl believe that the "choke on the carb" should be adjusted and set dif for colder weather? im going to take it to my mechanic again after christmas and ask him of this. does that sound right to ford mustang ppl who know more than i do? i am honestly an amateur in owning a ford. (literally i have had 2 civics,, 2 accords (own one still) a maxima and an eclipse all 5spds but never the pure HP of a stang; i could work on them all day, but obviously a DIF world here) thanks for the help folks!!! BEN

dawson1112

Check your choke and see if it is an electric or manual type choke. Take the air cleaner off while the engine is cold and verify that the choke is closed . If its a manual choke with a thermistor spring then as the engine warms the spring will expand and open the choke. If it is an electric choke it still has a thermistor spring but a 12v feed heats the spring slowly and pulls the choke open. There is also a fast Idle cam and when the spring is cold and you initially pump the accelerator the spring pulls the choke and fast idle cam into position for a cold start. As the engine warms under this fast idle the spring is heated and expands allowing the choke plate and fast idle cam to return the normal operating position. Once it is up to temp and you tap the accerator it releases the fast idle cam and choke and allows the choke to open .
With the air cleaner removed start the car and allow it to fast idle till it is up to temp and then kick the throttle a little and see if the choke opens up and the idle comes down. If the choke plate is not opening all the way up it will cause problems as it causes the engine to run far to rich. Luckily the choke spring is adjustable for a lean or rich condition. There are 3 screws on the outer ring of the choke spring and an indicator that says lean / rich if you loosen those screws a bit you can set the choke to open a little leaner by turning it in the lean direction. When the car is up to temp you want that choke plate fully open , so by turning the choke spring toward the lean position until it just gets the choke plate open it will set the choke to be fully open when warm .
Some pple in the summer will turn the choke spring so it never closes or is always in the open position. I had a 68 302 in a 95 mustang with a edelbrock carb and never had the choke hooked up because I didn't drive the car in the winter . It started fine with out it.

twocent06

thank you very much, that was very informative. i will relay this information back to my mechanic and have him adjust this with me

twocent06

actually tried a remedy after an older friend of mine who has an 87 gt with a 302 that is fully carb on his as well; he suggested running a bottle or two of 91pct rubbing alcohol through a tank and just flooring it and hammering through every gear. said from time to time he has done that through his and helped.. was scared to at first, but after reading some online stuff and talking to another person who has done this method, i did try it. i will admit it helped alot! after a few mins of driving and instense popping and heasitating ans sputtering it started to get better progressively until a little later and 2nd and 3rd gear are at FULL power again and can hammer it with no regard and it moves again finally.. 4th and 5th gear still are perfect but are way better. and first just gotta rev up a little still on the clutch and keep rpms above 1 now. so hoping to adjust the choke and half this fully solved. but did want to tell folks the old alcohol in the gas tank did help me a great deal..