I got a diagnostic ( spelling correction??) for my car and 8 codes came up. This is a 2000 Prelude SH. I just rebuilt the motor and dropped it in. The car turns and runs but sounds like it's miss firing. And the idle is messy. Well, 4 of the codes says i'm miss firing in all 4 cylinder. How can the car still run if i'm missing in all 4?? 1 says knock sensor. how do I fix that?? 1 is my o2 sensor, but I already knew that. And I have 2 other, circuit 1 and bank 1. What's that?? Maybe if I fix these problems, my car would run a LOT better. Can anybody help??

 

ha you're fucked 8 different ways.

 

As far as the misfiring, perhaps the ignition wires are installed wrong at the distributor. That's the first thing I'd check. The cam timing could also be wrong. That's the second thing I would check. Knock sensor code means either it's unplugged or damaged. Better recheck the last two because "circuit 1" and "bank 1" do not make sense. What were the code numbers for those two?

Don't mind RAB, he's just an ***

 

Geeze, with that many codes I would try swapping ECUs first to make sure your ECU didnt just take a dive.

 

Yes, I've been done 8 different ways. haha but man. It surprised me. I'm pretty sure I have the spark plug wires in right order with the distributer. I used a helms manual to locate each wire. How do you get to your knock sensor?? I have an SH, and it seems really hard to get to. how do you know it's damaged?? I'm sure I connected it though. I have another knock sensor so i'll try to replace it if I can. I gotta go recheck on the last 2 b/c I was confused about it too. I got the diagnostic at autozone. The guy wrote down: 325, 135, 300, 301, 302, 303, 304, and 1399???. not sure bout the last one......

 

On the SH you may have to remove the intake manifold to be able to easily get to the knock sensor. Underneath the ATTS unit is in the way. If it is connected, then it is damaged. You know because you have the trouble code for a bad sensor.

If you are positive that the ignition wires are in the correct order, check the cam timing next.

325: Knock Sensor Circuit Malfunction
135: Primary Heated Oxygen Sensor Heater Circuit Malfunction
300-304: Misfire in Cylinders 1-4

There is no 1399, get that double checked.

As 4bidden noted, there is the possibility that your ecu is damaged. However, being that you've had your engine out, rebuilt, and reinstalled, these problems are most likely real and the ecu is fine.

 

if you fix your knock sensor and o2 problem i will bet that your misfire codes will dissappear. i garuntee they will

 

i've had phantom CEL codes on my car too, normall comes from the obd2 reader jsut making stuff up. For the longest time, when I would get my too lean CEL, i would get another code that would say fuel trim malfunction. Looked in my helms manual and it wasn't there.

1342 is the firing order on a honda, 1 is marked on the cap, go clockwise around to make sure everything else is ok. But i would definately change out the o2 sensor, that oculd be giving you all kinds of hell if its dead, since the car would be forced into safe mode, same with knock sensor, also, i'm sure you've checked, but is the area above the plugs clean? like where the wires connect to them. Have you changed the plugs?

I borrowed a friends teg this week and got misfire in #2 & #4, confused me until i remember he washed his engine that day. I pulled out the plug wires and found small amts of water by the plugs, causing the signal to ground out.

Check your grounds too, if you don't have good grounds on teh engine, then you may not be getting a good ground, which can cause the misfires and all the other sensors to go nuts.

 

It might be 399 instead of 1399. I'll go back and check on it. Where's the primary heated oxygen sensor heater circuit located at?? How do you check the cam timing?? I had a lot of people tellin me that but i seem to can't do it. Do you suppose to rotate the distributer?? b/c i can't turn it. when I check my spark plugs, they are pretty black. Can that be why i'm misfiring to??

thanks for helpin me out...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by junbb1 &raquo;</TD></TR><TR><TD CLASS="quote">if you fix your knock sensor and o2 problem i will bet that your misfire codes will dissappear. i garuntee they will</TD></TR></TABLE>
^^^This is probably correct. I would still double check the cam timing.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SHhh__VTEC &raquo;</TD></TR><TR><TD CLASS="quote">It might be 399 instead of 1399. I'll go back and check on it. Where's the primary heated oxygen sensor heater circuit located at?? How do you check the cam timing?? I had a lot of people tellin me that but i seem to can't do it. Do you suppose to rotate the distributer?? b/c i can't turn it. when I check my spark plugs, they are pretty black. Can that be why i'm misfiring to??

thanks for helpin me out...</TD></TR></TABLE>
There is no 399 either, you will have to double check that. You could always pull the trouble codes yourself, rather than having someone do it with a scan tool: http://www.hondaprelude.to/art....html

As said above, you might be misfiring because of the bad O2 sensor. The heater circuit is part of the sensor. If you are getting the heater circuit code, either the sensor is unplugged or it is damaged. If it is plugged in, you should replace it.

If you know nothing about checking the cam timing, have a reliable honda mechanic do it. It's a bit involved to try to coach someone over the internet on how to do that. Your cam timing has nothing to do with the distributor on a 5th gen.

 

Yea, i figured the timing has nothing to do with the 5 gens from what the helm manual said. I have a problem about the o2 sensor. i had the o2 sensor code come up for a long time. even before the engine rebuild and the car seem to run fine before. I went to honda to get that fixed and they couldn't even clear the o2 sensor out either. A new o2 sensor was replaced too. As for the spark plugs, i'm gonna replace them to see what happens. I'm really stressin over this. Makes me wanna get ride of the lude and get someting else....

 

ok, the heater code is generate when the 1k resistor that is present in the stock harness is not getting power, moral of this: basicly, there are 4 wires to the o2 sensor, both primary & secondary. green, white and 2 black ones. green is signal, white is ground and the two black ones are the o2 heater. if your primary o2 heater is going out, you normally change the o2 sensor, yet if this doesn't fix it, and honda sent the car home with you that is a big problem. If the code comes back, that means there is a short in either in one/both of the black wires running to the o2 sensor or the ecu is bad.

5th gen preludes have timing set by CAS, basicly, is your timing belt on correctly.

second, fix the knock sensor.

another thing to check, when the o2 sensor was replaced, was it replaced with the correct o2 sensor?

if your plugs are black, that means its really rich, which means its misfiring causing not all the fuel to burn, hence being black. why not pull the distributor cap off and make sure the rotor is ok, but my thought is you could have the timing belt off some, which is causing the rotor to ignite the cylinders at the wrong time, creating a misfire. you are probably off a tooth on the cam gear.

 

I see what your saying. When I put the flywheel to tdc, the cam gears are at tdc too. the lines on the cam gears are lined up straight. Either that or my eyes goin crocked on me. I'll change out the knock sensor when I have time. I found 2 ground wires and grounded them out, and now the car sounds a little better. I idle can go about 1100 the lowest before bogging out, which is better than before. The engine can stay running on it's own now. I change the spark plugs and ran it for a few minutes then pulled them out. They turn dark again.

I have another question. If my timing is bad, What if I hook up an MSD digital 6+ to it?? Will it help?? I had my MSD for a while now and hadn't been able to use it either. What do ya'll think??

 

I would recommend not installing the MSD unit until after you sort things out with your current problems. Adding new equipment won't solve your problem, and can make matters worse/more complicated. Troubleshoot your problem methodically. It sounds like you have a Helm manual in your possession, so that should help in the process. You'll figure out the problem. I think your number one priority should be replacing that O2 sensor.

 

Are you sure bout the o2 sensor?? My car ran fine before when the o2 sensor wasn't working. That's gonna be a big problem since i couldn't get honda to fix that. How bad of a damage if my knock sensor is damage?? i'm probably gonna change it out tomorrow or next. Is an ECU a plug and play or do I have to program it to work with my car?? If my ECU is bad, can it effect my o2 sensor?? Like frying a wire of the o2 sensor?? I dont think my o2 sensor is messed up but I think I fried a wire. I was messing with a wire from the o2 sensor and accidentally touch the wire (open wire) to the car and grounded it out. Dont ask me why. I still feel stupid for doing stupid stuff. hehe Can that mess up my ECU???

 

My car is running smoother and it idles lower now. I replaced the distributer rotor but hadn't change the distributer cap. I'm gonna change it very soon. I fixed the knock sensor problem. Took me a few hours b/c taking off the intake manifold is a bi*ch. AND putting it back on. I went to get another diagnostic and now 6 codes came up. They're o2 sensor, multifle misfire, and misfire in 1,2,3, and 4. Hopefully when I change the distributer cap, My car will get better. I've seen like crane distributer caps and some clear caps. What's a good one to use and any links to them?? thanks....

 

1399 is a generic code- missfire any cylinder