Serious carb issues, 88 LX 4dr, Help!!!
I'm having a series of issues that seem to have been tracked down to carburation. I'm not that savvy on Honda's yet, and still re-learning 2 years of High School auto-mech that is quickly coming back. Please bare with me if I seem to be long winded.
I bought a used 1988 Honda Accord 4dr last month. 133k miles, 5spd, new Michelin tires and a very clean interior. It's only issues are no AC because of a missing belt and the clutch on the compressor dying, and a slight running issue that I have narrowed down to the carb. To narrow it down to this, I have changed cap, rotor, plugs, wires, and checked all vacuum lines for leaks with carb cleaner and patience. I've also painstakingly noted what the symptoms are, and found out when/what/where/how everything happens.
To start off my description, let's start my day. When cold and after sitting overnight, the car starts perfectly. Pump the throttle once before starting, and she's up and humming with the high-idle choke engaged and working. Wait 2-4 minutes, and I begin to drive to work. Running fairly cold, it's like a new car. Runs perfectly, no complaints. After about 10 minutes, the motor begins to warm and problems begin to show. During light acceleration, the motor seems to stumble, and hesitate sometimes, as if it is starved for fuel or perhaps not igniting a cylinder. This happens from anywhere near idle to 3000RPM, from 1st to 5th gear. Sometimes, during shifting, the motor will seemingly hang on to the throttle a little and increase RPM after engaging the clutch. It usually is just a short blip, but it doesn't go back down as fast as when the engine is behaving properly.
The stuttering goes away under harder acceleration and higher RPM. At 2500RPM, in 5th gear steady at 65mph, you can feel the stuttering. It can often be pretty pronounced. At 3100+ RPM, steady at 80mph, there is no stuttering. It seems that if either the vacuum secondary on the carb is open, or there is heavy throttling and accelleration, the stutter is non-existant. It runs like a scalded dog, for what it is, when the throttle is open and under that high accel condition. The throttle doesn't hang when shifting either, especially if RPMs are about 4000 when shifting. The car has also idled high from time to time at a red light or two, symptom goes away usually by tugging on the gas pedal.
With those symptoms in mind, I have a couple of theories:
1.) It runs too good cold and too good at high RPM/throttle to make me think this is an ignition or vacuum problem, but I replaced or diagnosed those first anyway.
2.) The car runs GREAT cold, I almost want to wire the choke shut.
3.) The car runs GREAT under hefty throttle, I almost want to wire the secondary open.
4.) I know nothing about adjusting mixture on these carbs, or their design. Float sticking? Mixture way wrong? Ugh.
5.) The throttle is sticking, somehow. It may be a throttle return spring?
Ideas, suggestions, and hints? I am prepared to rebuild the carb myself if it's not too daunting, or perhaps buy another to rebuild and swap on. Could this be a fuel pump? Under high throttle, without symptoms, I wouldn't think so. Fuel filters are all new, and I'm just confused as it gets. The CV axles are going to need replacing eventually, as this has gone on for a while and slack/takeup you feel has to be wearing on them and the tranny.
I am in the Austin, Texas area, and would love to take this car to the right person for a tune up and tutorial. I don't want to be ignorant of the fix, so anyone not minding a little shadowing would be helpful. I'm broke, and cheap, so keep that in mind.
Thanks again, enjoying the list and my new car! The plan for the future for this thing, a B18C or better swap, fogg'd to 300+ hp. Not a single body mod from the outside detectable either, a true sleeper. Two years, at least, but I have time.
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