p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

2000 Honda Civic Dx. Car starts misfiring as it warms up. Has total loss of power. Won't go over 30mph. Misfires bad. Check all ignition componets. PLZ HELP!

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

What ignition components did you check? How did you check them? Try a good known working distributor and don't drive with it misfiring as you're going to kill your cat.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

yeah its been sitting for a couple weeks. Checked resistance on coil and IM. got IM checked at auto parts store also. Resistance of all sensors in dizzy are in spec also. Continuity to and from ecu is good. Power at dizzy is good. I have fuel. Dizzy has all new parts from previous owners trying to fix the issue. At this point I'm suspecting timing or a blown headgasket. I'm going to do a compression test asap to maybe give me a better idea of the problem.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

is it only as the car warms up or is it all the time?

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

this is whats wierd. it does not start doing it as soon as the car starts, rather as the car is warming up. As the temp needle is rising.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

change your cables. and spark plugs. maby even injectors. but cable and plugs first.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

I think he's past just changing parts out. Identify tbe problem first. Check your timing as its warm check your ecu.
Check the timing as its missing. Check your fuel. Check all your motor sensors.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

yeah definatly past swapping parts. What do you mean by check my ecu? I'm trying to avoid loosing a ton of time by checking all the sensors. Has fuel.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

whats compression of a y7 at optimum level? service limit?

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

If you dont want to waste time take it to a shop.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

I'd do a leak down test as well.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

could be the ecu. something simple injector wires crossed or wrong firing order. also check that the spring that goes between the cap and the coil is there..trust.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

I meant I don't want to waste unnecessary time or money for that matter. Checking all sensors in my opinion is a waste of time. I’d rather find a lead and follow it. I don’t go about things irrationally.

I don’t have access to air but leak downs are good. I thought I would just do a compression because based on the results it may indicate timing being off or blown head gasket. Coil discharge spring is there. Wires are in correct place.

Thanks for all suggestions. More will be appriciated.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

Obviously your. Car is running fine. When your engine is cold your ecu runs in closed loop as it heats up it switches to open. Meaning it reads signals coming from your SENSORS. There's an obvious fluctuation happening causing a misfire. Again check your sensors. That last code is it p139? Check your o2 sensors and voltage coming oout of it. If you still wana be ignorant about the fact then I will post no more

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

Also have you listened to all 4 of your injectors to see if they are working (use a long screwdriver and hold the handle to your ear and the other end to the injector to listen for the click). Also I would pull the manifold shield on your exhaust manifold and see if you have a crack in it. It may not cause it to throw a CEL for the O2 but it could throw off readings causing the other codes.Cracked manifolds on these models is very common.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

No bro. Your car runs in open loop when its cold. Then closed loop when warm. If the car only does this when warm then check the primary o2 sensor. It could be sending false voltage. It should be from 350mv to 850 fluctuating.

Another thing to check as well is for vacuum leaks and check fuel pressure as a multiple cylinder misfire has something to do with all cylinders.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

Turbohatch, you have it backwards. Open loop is when the engine is cold and runs on set parameters. Once the car is warm it goes into closed loop and looks at sensors to adjust air/fuel, timing, etc.

The first thing I would do is hook up a scanner that is capable of reading live data. You can see if/when the car switches to closed loop, and see if the misfires are starting before or after that happens. Being able to see the fuel trims is great for diagnosing misfires and you can see what the ecu thinks the sensors are doing.

Sure you can do things the hard way, but chances are a scan tool will give you a good idea what's happening without even popping the hood.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

Yeah I knew I had it backwards didn't feel the need to change it since he's gonna prolly ask another question beofre making checks

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

Not necessarily. A perfect example is an Odyssey I had at work I while back. It had codes p0300,301,302,303,304,305,306. 1 dead coil on cylinder 5 was causing everything.

This is another benefit of a good scan tool. Instead of believing the codes, I was able to get into the misfire monitors and see for myself which cylinder was dead. Took all of 5 minutes.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

Also see if the fuel pressure regulator is leaking gasoline into the intake manifold through thre vacuum hose

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

ok ill check sone of this. i wanna say it stayed rich(850mv or so) after it should have switch to closed loop. no signs of a rich condition though.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

p1399

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

Are you just guessing at what the readings are? Your useless take it to a shop

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

Forget checking u need to verify if these components are working properly or not. Ohming them out may be helpful for a coil or an ignition wire but to properly check your inputs for the ecu, meaning tdc, cyp, and ckp sensors you will need an oscilliscope and a good scanner with data stream. We are one of the better diagonosic shops in New Jersey and specialize in problem cars and most shops dont take the time or want to invest in good diagnostic equipment so if you cant fix it yourseld or dont have the know how make sure you take it to a reputable shop. If it will help you i cant put a link up of the engine control wiring diagram so u know what wires to go after when u are testing components. Without seeing how the car is running it is very hard to diag a car over the computer, but just from experience as u might already know the ignition system has been the weak link in hondas for a long time so make sure you check it good. And like other people have said check your o2 sensors and see if they are switching and if the car is getting into closed loop. We have seen bad o2 sensors make cars run very crazy in the past and not set a code. Hope some of this info helps and let me know if you need that diagram.

Re: p0300 p0301 p0302 p0303 p0304 p1399 NEED HELP! EXPERTS PLZ
 

We have been seeing alot of this with the newer Toyota cars and trucks. Are u at the dealer or a private shop? Which scanner were you using. We have the older pgm that honda did away with in i believe 2004 but Bosch bought Vetronix and their new software is pretty good coverage for Asian vehicles.