I just bought a 1982 Honda Accord with some engine troubles. Here's what's happening.

The engine starts right up when I give it a bit of throttle, cold or hot. It has a fairly smooth 1300 RPMs idle after about 10 second of running. Once the engine warms up all the way it will idle, but the idle is erratic and will go anywhere from 750 RPM to 1200 RPM and will occasionally dip to about 500 RPMs.

When accelerating it seems to have decent power and it accelerates smoothly and sounds VERY good. When I let off the gas to decelerate it kick hard... Like it has bad motor mounts, but once its over the kick it sounds and runs smooth while decelerating. Here's the part that's throwing me: When at a constant throttle setting and load (driving 40 MPH for example), it runs smooth for about 2 or 3 seconds then start stumbling... or missing... It happens gradually and takes full effect after about 5 seconds of this stumbling. It is almost not drivable when it is missing/stumbling. To drive it I just adjust the throttle slightly every 2 or 3 seconds. Any idea what I should look at first? I was thinking the timing might be off.

 

I have the same car, just rebuilt the head w/gaskets.

Check ALL vacuum lines. I had a couple broken ones after putting everything back together after the head was back on, especially the half inch one with 1/4 inch ID, coming from the anti-afterburn assembly. It was hard as a rock and snapped when I was putting it back onto it's check valve.

While you're checking to make sure none are broken (note around the stems of where they push on to, that's where they can break the easiest) make sure that they are all connected. I had a couple disconnected and I was able to get it started, but it would run for 5 to 10 seconds and die, with my foot on the gas hovering around 2,000 RPM's. After I found one vacuum leak, it would run for about 15 seconds then die. That's when I found the anti-afterburn hose leak.


Did it all of a sudden start doing this, or was it like that when you bought it?

For grins, check the timing too. 12 degrees BTDC. If you have a manual tranny, you can time it thru the window on the transmission bell housing. You have to take the vacuum hose off the distributor timing-advance diaphram and plug the end of it with a screw or something that fits snug, in order to time it.

I would also check for fouled spark plugs, and the condition of the cap and rotor.

How many miles on it?

r/
-Ian

 

Thanks for the info. This is a fun car to work on.... Now if I can only get it to work.

I bought the car for $75 in quarters from a guy who had it sitting for 8 months who got it for free from a guy who didn't need it anymore. I think this counts as buying it 4th party. It has 172K miles, doesn't smoke, sounds good, and is a total rust bucket. I thought it would be a fun project car and eventually a winter city driver.

I just replaced the sparkplugs (horrible shape!), the spark plug wires (just to be safe), the distributor cap (a bit corroded), and the rotor (horrible shape!). I find 3 vaccum leaks and fixed them all. Now the idle after about 10 seconds from a cold start is OK at about 900 RPMs. When driving it when its not up to operating temperature it routinly stalls when the RPMs shift from high to idle after hitting the clutch. Once the engine is warm it idles at about 1500-2000 RPMs a little erraticly. It is still bucking when driving at a constant speed, but it is now better. I still think I have some vacuum leaks. I tried to check the timing but the timing mark isn't stationary, nor is it in the right place because of the high, erratic idle. Once I get that fixed I can check the timing.

I found today that the Idle Cutt-off valve is not plugged in, the wire is loose. Where does this plug into and what does this valve do? For the intrest of eliminating problems, I have read that's its possible to strip all emissions off the carb and plug the holes. I want to do this, but what do I NEED to keep to keep it running?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rs2k &raquo;</TD></TR><TR><TD CLASS="quote">I found today that the Idle Cutt-off valve is not plugged in, the wire is loose. Where does this plug into and what does this valve do? For the intrest of eliminating problems, I have read that's its possible to strip all emissions off the carb and plug the holes. I want to do this, but what do I NEED to keep to keep it running?</TD></TR></TABLE>

That's the electronic piece on the passenger side of the carb, I believe? There is a wire harness behind the carb along the firewall. It has a few connectors (snap in pole type). The one you are talking about, is a red wire, and white/blue wire I think. (It we're talking about the same valve) but the same harness goes up to a connector that is on the air cleaner housing (drivers side), not sure what it is, and it also has a pair that goes to a round l'il sensor on the intake tube of the air cleaner. Not sure what the name of that is either, Sorry, BUT, look for any loose wires. They'll have the identical colors on them.

Try and match up the vacuum hoses to the diagram, the hoses should be labeled by numbers correlating with the chart on the hood. There's still a leak of some sort if it dies when it's cold, or it's out of time and the idle set screw is out of whack. (it's on the back of the carb at the firewall. If you can find it the first time to adjust, after that you can reach down and adjust it without removing anything.

YOu may not want to remove all emissions off, as you may lose some power, even though it will still run "okay."

I'll look into my shop manual for your symptoms and see what it suggests.

 

Thanks. Off a hunch I disconnected the brake switch +12V wire and connected it to the idle cut off valve. That helped the idle TREMENDIOUSLY, but it still dies when cold. After about 30 seconds of warming while giving some gas the idle become stable at 950-1000 RPMs, but if I drive it and let the engine settle down while the engine is still not quite warm it will die.

Once the engine is warm the idle becomes solid somewhere between 1500-1600 RPMs and when I let the engine settle down while driving it will fall to about 1000 RPMs then climb back up to between 1500-1600 RPMs. I am still getting major bucking under very light acceleration; very light deceleration, and steady cruising. I have a feeling I have a vacuum leak somewhere around the tangled mass of vacuum lines around the carb. I just put a top end cleaner in the crank case (sea foam) and I will change the oil next week. I will trace the vacuum lines out and replace every questionable link then. What's the chance of having a bad vacuum actuator?

Oh one other thing... I used a timing light today and when it was hooked up to cylinder #1 (the cylinder on the drivers side) I could not see the timing mark. I only found it when I hooked it up to cylinder #4 (passenger side) thinking that I had the cylinder numbers mixed up. It wasn't until I double checked the Hayes and Chilton manuals I have did I discover I was right the first time. Can the timing be THAT far off??? Mind that the engine RPMS was erratic and around 1700 RPMs when I checked it, but even when engine RPMs dipped below 1000 RPMs when on cylinder #1 I couldn't see it. When I did see the mark when I was on #4 I noticed that the timing varied regularly with engine RPMs and that it was so advanced at 1700 RPMS that it left from view of the window.


Slowley but surely... It's getting better.