rshirey9872

Alright, here is some background. I have a 2000 Honda Civic EX, Manual, Coupe with roughly 144,000 miles on it. The previous owner claims to have rebuilt the motor but I have no proof. The only modificaions from stock on the motor appear to be a cold air intake. I have recently replaced the air filter, plugs, wires and distributor cap. The CEL has been on since I purchased the car due to the fact that it has no cat. on it.

Recently, the car has been running fine while it is cold but after it reaches operating temp, it starts to idle high (1500 - 2000). The idle will also fluctuate rapidly when sitting at a light or stop sign. Next, the car seems to stutter for lack of better terms when taking off from a stop as though there is a delay between me pressing the gas and the engine getting the fuel. This only last for a second and then it goes just fine. The next and most annoying issue is that there is a single jerking motion associated when I initially engage/press the gas peddle while moving or when I let completely off the gas. It is hard to explain this other than when I am coasting and I first press the peddle, the car jerks fairly hard one time and then is fine. It does the same thing when I let completely off the gas to coast. It is a single jerk as though something is engaging/disengaging and it only happens when the car is warm and has been driving for a little while.

To date, I have had the shop look at it and they have replaced the IACV, PCV and now the TPS. They told me they have checked the vacuum system and found no additional leaks. Just today, I removed the "Backup" fuse under the hood to reset the ECM and then after replacing it, started the car and let it run for about 15 minutes as I had seen recommended in other posts. I then shut off the vehicle and started it again to take it for a test drive. This obviously cleared the CEL and the car idled fine and seemed to run great for about 2 minutes. Then sitting at a stop sign, the CEL light came on and the idle jumped from 1000 to 1500 and the symptoms were all present again.

At this point, the shop I had been going to said they are lost and recommend that I take it to a Honda Dealership and have them start looking at it. Can anyone please help me out? I really don't want to start from square one with Honda and pay their $130 diagnostic fee unless I have to. PLEASE HELP.

Hondaguy83

What cel code?? I'm thinking could be mechanical head issue but that's worse case scenario.

97_ek_coupe

There has to be another cel code. The cat missing doesnt affect anything.

Hondaguy83

Prob vacuum leak. Check o2 sensor reading and if possible disconnect o2 sensor and apply propane in manifold and see if it goes down. You'll know its a vacuum leak if it does.

BTe

Might be Idle Control Unit for the high idle. Got a diagnostics from an inspection and I have the error code report laying around somewhere.

pityocamptes

I agree.

moejoepotatoe

Check all of your throttle linkage, maybe something is loose and snagging everytime the cable is pulled. That would be a good place to check first after that check fuel pressure. Its also a good idea to replace the rotor when ever you replace the D-cap. If its not making good contact wen it spins it will definitley sputter and skip wen you accelerate unless you take off really slow.

Hondaguy83

Check short term fuel trim and long term fuel trim and your scanner and also see readings on your o2 sensor. You'll know if your running lean or rich for sure and also many scanners can control the idle air control and do test. One major thing is some mechanics must sometimes check things twice!!

rshirey9872

Thanks everyone for the input. I have been really busy with work and I don't have a scanner or anything like that so I plan on taking it in to a shop again and I will ask them for a report on all the codes that the CEL is kicking back. I am starting to think more and more that it has to be a sensor or computer issue because if I clear the CEL, the car runs fine and idles normally but as soon as that CEL comes on, it idles high and the whole throttle issue returns. I will post any new information as soon as I get it into Honda for a diagnostic.

As for the O2 sensor, that could be the issues as the car has been giving me an O2 Sensor code since I bought it. I don't remember the code but the guy I purchased it from, hooked his scanner up to it and showed me that was the issue when I bought it. Thanks again everyone. I just want my civic back to being the reliable, gas sipping, daily driver it should be.