I have a 2000 Accord ex coupe. F23A1 4cylinder VTEC. 136'000 miles. I am not sure what the prob is and could use some help.its not throwing any codes but really running rough. Especially going up hills it sounds like it's out of gas and when I am coasting down hills once I get back on the gas it blows out smoke. But that's the only time it smokes. I've changed plugs wires rotator timing belt. I not sure we're to go

 

Did this happen out of nowhere? Any chance you filled up with gas right before you noticed issue? Any recent work done on your car?

Running rough isn't descriptive enough. Are you noticing loss of power where the car takes much longer to get to speed? Is the power loss when going up hills and down hills?

 

I had noticed a loss In power and I was finding myself halving to drop down a gear to go up hills we're i wouldn't have to do in the past. Not knowing what the previous owner had done to it for the upkeep I went ahead and started with the basics of plugs and wires and distributor and it seemed to help for a little while but then it slowly getting worse again so I changed the O2 sensors and the map sensor and the timing belt. Which again it seemed to help for a few months. Then I started noticing when going down hill and just coasting in gear soon as I started giving it gass again it would blow out smoke but I can't get it to smoke in neutral. It also sounds like it's out of gas going up hills and loosing power. it's also not throwing any codes I was going to change the injectors out tonight but my only concern is I don't know how Manny CC's there sapose to be it doesn't say at the part store just that to change the fuel filter if changing the injectors but doesn't make much sense since its not replaceable. And I'm hoping that I can pull the fuse for the fuel pump to get the fuel out of the lines instead of having to unplug the wires from in the trunk

 

I wouldn't throw more parts at your car. I've see a lot of new parts fail out of the box and make troubleshooting much more difficult as you have 2 problems instead of the original.

Since you have a 2000 accord, you can pick up an OBD2 reader that can read live data. There are cheap options online that you can use blue-tooth to connect to your phone. I would look at fuel trims first to see if your engine computer is adding or removing fuel to maintain proper air/fuel ratios.

 

I have a code reader and normally they will run between -3and 3 but I have seen it sometimes go to -29. But as soon as I let off the gas it drops to 0. If I let the gears slow it down some it will even backfire. And anytime I leave it in gear and coast down hill and get on the gas it will smoke. But if I put it in neutral I can rev the **** out of it and no smoke. I changed the fuel injectors and it was not having it wouldn't idle or stay running. So I unplugged the fuel pump at the tank to relieve the pressure like I did before I changed them started the car up and the damn thing was running just fine. And yes you read that right.as soon as I plugged the connector at the tank back in sputtered and shut off. I've done a compression check and all 4 cylinder's was around 180. It has a Cadillac converter about a year old. I've changed the O2 sensors,map sensor,plugs and wires, timing belt, I keep thinking something is going to eventually show it's self but I don't want to trash the motor waiting for it. I've asked 2 different mechanics they have no idea

 

That's not a good sign when the repli it is so quiet

 

Suggestions....

1) Ignition coil
2) Check fuel pressure
3) Air filter
4) Throttle body needs to be cleaned
5) Vacuum leak
6) Battery Cables good/ connections good (not corroded)?



Is it automatic or manual? Daughter used to have a 1998 Accord, but she sold it last year.

 

Sorry - I missed your last response.

Does the fuel trim drop to negative ~29 when you are at high rpm?

 

It does go farther in the neg when higher rpms. But as soon as you let off the pedal short term hits 0. Long term usually hits -4 or so. I also never get a check engine light. I done a compression test and all 4 cylinder's was at 180. But now I noticed the cooling fans arnt kicking on and the live data on the scan tool is not going up over like 185 and the dash gauge is running were it always has. The cluster lights got switched to blue LEDs and they must have put the gauge needle back on in the wrong spot and it is like a quarter off. So it reads 3/4 hott but it's 1/2. I went and had a water pump put on it last year bc I was worried about it overheating but the fans would kik on and the temp reading from the scan tool is how I found out that the gauge was reading wrong. But now the fans arnt kicking on and the scan tool is not showing the temp getting hot enough to Kik the fans on

 

The fans won't turn on unless your coolant temperature reaches a set temperature. You may want to get an OEM honda thermostat, so you are sure the thermostat opens/closes at the same temperature.

If your short and long term fuel trims stay somewhere less than + or - 10 at idle, then drop to lower numbers as you increase the rpm, then you need to test your fuel pressure.

If the trims are very low at idle and improve towards zero as you increase rpm, then you would look for vacuum leaks.