I have a 94 accord that I recently bought for a work car. When I got it home, I started to work it over and fix issues that I noticed. First issue, it had check engine light and after reading the codes, I got a code 9. I did my homework and found out that a code 9 is for the tdc sensor that is in the distributor. I used the troubleshooting here on this sight to find out that the sensor was good and I bought a used ecu to do away with the code. Installed the ecu and it fixed the check engine light. Now for he current issue which is two fold. I noticed that once the car is warm, it hesitates and stumbles while driving almost like the TPS sensor is going bad. It will do it until I floor it and then it kicks down and we are accelerating again. The second part of the issue is that the temp gauge reads nothing. If I get the car warm by driving it, then come home and let it sit it will register a little bit but as soon as I drive, it drops below the blue line. I am assuming it is the thermostat that is stuck open but I have heat in the car. My question is can the operating temp cause this problem with the driving.


What I have done:
changed plugs wire and distributor cap
Swapped ECU with known good one
Purchased thermostat and will install in the morning

 

Normally a common issue on these cars are the egr ports and for your car you have a plate that is more easily accessible than the 90-93 cars. You can look for a video by eric the car guy on youtube as he has a vid on how to clean the ports and the egr valve. This assumes you have replaced your cap, rotor, and plugs.

For the temperature gauge since you have heat it would seem more likely that the problem is the "coolant temperature sender" that is located under the distributor. There are two sensors, one has one prong and the other is the two prong. You should replace the one with the one prong.

If you are going to replace the thermostat, make sure you get one from Honda. Only Honda thermostats are reliable as the aftermarket ones do not last long and do not have the failsafe built into them that Honda does. Don't try skimping and saving $10 on something that could fail and ruin your engine if it fails closed and causing your car to overheat real fast.

 

I had similar issues and had also switched out the coolant temp switch for the computer(not my inside guage). Long story short- thanks to help from this forum,it turned out to be my 02 sensor even though I had no cel for it. If it is an 02 issue, don't buy Bosch. On my third replacement(Denso this last time)

 

Yeah, you know what, just to check and see if it's the oxygen sensor that is lazy now, and assuming you have never replaced it, you could disconnect the oxygen sensor when it starts hesitating and run the car and the check engine light will come on but it will run the car with predetermined air fuel values. You can do this as a test measure to check and see if the oxygen sensor is the culprit.

 

Ok so today, I tested the TPS and found it to drop below .4 volts and while driving it varied in drop. I replaced it along with the fuel filter. I pulled the distributor cap off and tested the primary resistance as well as the secondary on the ignition coil. The car was warm and I was getting 13.4 ohms on the two spades on the coil. Secondary was at 29 which the manual says is within spec. I have the hitachi coil so I do not know if this is bad or not. As the coil cooled on the bench it dropped down to around 6.2 ohms of resistance which makes sense because of temperature. The Haynes manual says that normal is .3-.4 ohms at 70F. As far as the temp guage goes, I replaced the thermostat which was stuck open and it fixed the issue. I took the coolant temp plug off and placed a jumper wire in it and the cooling fans came on. I found the temp switch to be faulty and will replace that in the morning. As far as the hesitation issue goes, I am at a loss. To me the resistance in the coil seems to be well on the high side even if it was hot. 6.2 ohms is a lot more than .3-.4

I appreciate the help and suggestions in advance.

 

Remember to touch the leads together and to subtract that number from what you get when you do the primary test. However 6.2 ohms sounds way too high on the test that you're supposed to be below one ohm and there is another that should be above 13k ohms. I forget which is which but you should know when you test. Sounds like coil might be bad unless you're reading the mm incorrectly.

Don't forget to calibrate the new TPS.

 

https://honda-tech.com/forums/honda-accord-1990-2002-2/1994-accord-ex-misfire-stuble-under-acceleration-2895754/

7th post down has some specs.