Ok,

This is going to be a long story but I have a lot of information to give and I figure the more I tell you the better you can help me.

I have a 92 Accord EX Manual, I've had it for about 6 months. Ever since I got it it has had one kind of minor problem. From a stop, it would seem to not have any power for taking off...kind of stumble a little from a standstill and then go fine (I know I'm not dealing with a lot of torque right away but this felt different), it also wouldnt accelerate smoothly, kind of surge a little, not enough to feel like its stumbling or anything but enough to notice.

About a month ago the car started to have another problem. Occasionally at a traffic light the engine would idle down to normal idle then drop down to 200 or 300 RPM, stay there for a few seconds, then return to normal. This wouldn't happen every time and didn't really worry me because it never stalled and I could live with it.

Two weeks ago I was doing some maintenance on the car (change oil, rotate tires, etc) and decided to wash the engine. I used Gunk and rinsed liberally. I drove home (I was at my dad's shop) and everything was fine. A few mins from my house the check engine light came on but the car was still running fine.

The next day the idling down problem became MUCH worse. It would idle down and stall at almost every traffic light. I checked the code and it was a 43 which I was told was an ox sensor error (I found out later that was wrong). I replaced the ox sensor which didnt help. Around that same time it acquired the second and worse problem.

When I accelerate sometimes it will be fine, other times it will stumble hard almost to the point of no acceleration. Its not a smooth loss of power that you would expect from a fuel loss its hard and jerky like the loss of ignition sometimes that will happen for a while, other times it will clear itself up quickly.

My dad and I were trying to diagnose both problems. We found that with the idling problem we were able to stop that by putting a restrictor in the tube for the PCV valve. We know we are just making up for something else such as a bad sensor or vacuum leak but that did take care of that problem (though it does idle kind of rough) but the stumbling problem has me stumped. The computer has also thrown code 1 and 41 (ox sensor and ox sensor heater) (but while the engine was running smoothly which doenst make any sense.)

I have changed the PCV valve, checked for vacuum leaks (using starter fluid), replaced the Ox sensor, changed plugs, cap and rotor, checked the idle air valve (only for power), checked the TPS (shows a smooth progression of resistance which is well withing both limits listed in the Haynes manual) cleaned the battery contacts, checked the battery ground, and I'm sure more which I can't remember.

I'm going to put plug wires and a new coil on it tonight but I doubt they will help.

Oh yeah...one more thing. When I give it a little gas from idle I hear kind of a whistle sound, I pulled the air tube and it sounds like its coming from inside the throttle body, Im sure it wasnt there when I first got the car and I'm sure its getting worse.

I'm at my wits end with that problem and I cant just keep throwing money at the car. I'm sure I got water in something but what??? I hope there is a Honda guru on here that will know whats going on.

Thanks in advance and sorry for the epic story.

Kenny

 

Ok, so I've been looking through the forum and I think I will be able to correct the idle problem. It was low on water for a little while so there is probably air in the idle speed sensor I will clean that as well as the fast idle sensor and the throttle body in case there are deposits in there.

Which leaves the big - stumbling on acceleration problem. Please help me with this.

 

Do the plug wires, but hold off on the coil. It just doesn't sound like a coil problem. How many miles are on the car? How was it maintained before you bought it?

 

I had a similar problem on my 92 EX that was the TPS. I could not read a dead spot but when I unpluged it and let it set it's code and run on default, it ran fine. I drove it like that for 6 months and then the price of gas got so high I fixed it to get better economy. Unplug yours and drive it to rule that out as a cause of your stumbling. I f that's not it, plug it back in and clear your codes.

 

It has 142,000 miles on it and I have no idea how it was maintained before I got it (20,000 and 6 months ago). Since I got it I have replaced every maintenance part including the timing belt and have taken as good a care of it as I can.

My dad is brining the wires and coil after work so I'm going to go ahead and try them. If that doesn't work I will try disconnecting the TPS. I noticed that it appears to be riveted to the throttle body. Are they replacable?

Thanks again for your help

 

If your still going to replace the coil, at least put the wires on first and drive it. Never change more than one thing at a time or you won't know what the problem was. Since it only takes a second, I would also unplug the TPS before replacing the coil. It's an $80 part and in can't be returned if it's been mounted. The rivets for the TPS are not really rivets. More like tamper proof nuts. Cut a slot in them with a Dremel and remove them like a flathead screw. You'll have to search to find out what year/model TPS to ask for. I carefully cracked the case open on mine and cleaned it out with methanol while moving the throttle plate. I sealed the cover back on with silicone. That was over a year ago.

 

Oh yeah, for sure. I'm going to put the wires on..drive it for a day or so to see if that helps, then I'll unplug the TPS, try that out for a day or so, then if neither of those things work I'm going to try the coil. During this time I'm also hoping to clean the throttle body, and the IAC but I don't know if I'm going to have time.

Have you ever heard of the whistling sound coming from the throttle body when cracking the throttle just off idle?

 

Sounds strange. You ought to get your dad to get a throttle body gasket while He's at it. There only $2 or so. It's alot easier to clean the TB if you remove it and it only takes a couple of minutes to pull and replace. Then all that carbon doesn't get sucked into the motor and you can see if all the ports are free and clear. The idle air control is only three bolts and two little coolant lines and should also be a snap. The car you have is well worth the effort and with 142K miles, is just getting broke in. I have 240k on mine and it's not about to quit. I fully expect 350K.

 

Thats a good idea. I'll pick on up tonight. I really like the car and I'm not going ot sell it, I'm just a little frustrated with it right now.

 

Well, I just disconnected the TPS and before I left for lunch and man the car accelerates and decelerates so much smoother than it ever has. I'm not saying that the problem with the hesitation is fixed because it is intermittent but it sure feels better.

AMCKEE - When you were having your hesitation problem, would it go away at WOT?

THanks,

 

It would go away depending on how much I pushed the accelerator. A TPS is a variable resistor. They develop dead spots in areas of high use which happens to be that low mid-range that everyone uses in everyday driving. I never tried WOT when it was stumbling. I only use that if someone pisses me off.

 

this happened to me the day i bought my 4th gen with 182k miles. here is what ive done and it never came back.


new sparkplugs, wires, cap, rotor
new PCV valve and gasket (i think that was the culprit)
valve adjustment.
clean IACV with tb cleaner
take off FITV cap and skrew the plunger back in.
re adjust throttle cable (mine was too tight causing it to act like a vacuum leak)
clean TB with TB cleaner


i dont know which one of those fixed mine but i believe you have done just about all of those as well.

my intake manifold also was making a whistleing sound when i got it....turned out to be half the air filter inside the tube.

 

If I recall, though, your complaint was just a surging idle without the stumbling upon acceleration. I was the one that suggested for you to put a little slack in that throttle cable. Glad something fixed your problem. See what I mean about doing one thing at a time so you can nail down the culprit as well as gain a better understanding of what effects what.

 

Absolutely. I need to check my throttle cable. That's one thing I havent looked at. But once I get the hesitiation problem fixed them I'm going to go ahead and to all the rest of the great idea's I've gotten : )

Thanks again and We'll see how she goes.