I have a 1993 EX. After the engine warms up, it hesitates at low throttle. For example, in parking lots or crusiing at about 50-60mph. There is no problem when the accelerator is pressed more, like when getting onto the highway, or leaving a stop. It is a steady hesitation, not surging or eradict.

When on the interstate, with cruise on, the check engine light comes on. I stuck a jumper in the error plug and I am getting a 43 error code. The Haynes manual I have has nothing on this error code. I found a reference elsewhere on the net to that code being about the oxygen sensor. However, no elaboration on a specific issue.

I have already layed down $500 to a tune-up place to replace the secondary ignition as they and I really felt I had a cylinder not firing. It was not a total waste. I had leaky fuel injectors and a shot distributor. Still, I took it in to fix this specific issue and it is still not resolved.

If anyone here knows about error code 43 or the symptoms, I would appreciate it. Even if I can not do the repair myself (at this point I need to save the $$$$), I will know what I am dealing with when I take it to the local Honda specialist shop.

Thanks.

 

If you are having a running problem at low speeds and idle, check for vacuum leaks. If there are no vacumm leaks and the fuel presure is in spec, code 43 is usually a bad o2 sensor.

<edit> Ive been seeing a lot of leaking intake manifold gaskets on 4th gens lately.

 

Ok, I checked the voltage and such on the oxygen sensor and it appeared to be bad. I got another one, replaced it and the majority of the problems are gone. It now idles smooth and does not hesitate at a wide range of RPMs.

There is still another hesitation. This hesitation only occurs when I first take off from a stop. Then it only occurs when I ease away from a stop. If is step on the accelerator, it does not happen. It does not happen once I am moving at all. It is very noticable when going up my parents driveway, which is quite a steep up hill. Again, if I step on it (not smart in a driveway) it does not happen. FWIW, this has been happening since before the other problems got so severe. I figured it was just the early signs of the O2 sensor, but now that the other problems are gone, I think this must be something else. Perhaps this is a transmission thing.

That leads me to this question: should there be any hissing sound coming from around the area of the intake manifold? I have heard a similar sound on other vehicles (my van) and been told it is normal. I just want to eliminate a possible vacuum leak or intake leak.

Again, now, the entire secondary ignition has been replaced. The fuel pressure is fine according to the shop that replaced the FI seals and valve cover gaskets and seals last week and now, I have a new oxygen sensor.

I appreciate the help and I will report back here with anything I find out to help the others on the board.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by brianlmoon &raquo;</TD></TR><TR><TD CLASS="quote">

There is still another hesitation. This hesitation only occurs when I first take off from a stop. Then it only occurs when I ease away from a stop. </TD></TR></TABLE>
Disconnect the vacuum line from the EGR valve and drive it to see if the hesitation goes away. Sounds like your EGR ports are clogged up.