CEL #16
 

Posted this before the crash.

Had a 16 CEL suddenly.

I have my resistor box wired into the harness through a plug that mates up witht he injector distribution plug.

I pulled the plug and replaced it with the stock one, the light went out.

I then ohm'd out the box and connector and everything checked out at 6.2ohms per injector. I can't remember the stock resistance on the OBD0 boxes. Seems low though. Any ideas?

Re: CEL #16
 

Check your wiring. Then check it once more just to be sure.

Re: CEL #16
 

Are you sure you know how to read?

If everything traced out fine on the box and the wiring is obviously perfect from the plug to the injectors...

Re: CEL #16
 

Sounded like you only checked the box. :P

Did you check the injector resistance. 6.2 ohms isn't total is it?

Re: CEL #16
 

Check you don't have short somewhere. I swapped heads and got one injector wire clamped between the intake manifold and manifold brace. Eventually shorted out the wire and threw a code 16. Troubleshooting the code wasn't hard, just take a look through the manual.

Re: CEL #16
 

Can noone read?

Changed the wiring back to stock and I was perfect. If I plug the box back in I get the code.

I get 6.2ohms on the box, is that the normal? It seems low to me.

Re: CEL #16
 

have you changed your wiring back to stock. thats what i would do

Re: CEL #16
 

My bads.

I'll check resistance spec tomorrow and get back to you.

Re: CEL #16
 

Are you using the same injectors when you took out the resistor box?


What are the resistances of the injectors?

Re: CEL #16
 

Same inejctors as before. If there was something wrong with the injectors it would still be there, I didn't change them out.

Re: CEL #16
 

Thats low...should be about 9-10 ohms

Re: CEL #16
 

Thankyou literate hereo. I thought it was low, but what makes them just go out instantly like that?

Re: CEL #16
 

I have a Honda OBD1 box and it reads 6.3 for each. Others I have checked are around the same readings.


So are they saturated or low impedance?

The reason I asked about the injectors is are you trying to use saturated injectors with a box too? ECU might get low current feedback with that setup and throw the CEL.

Re: CEL #16
 

were you the one that had the post of the easy resistor box install?

Re: CEL #16
 

Total ohms in the system should be about 12-13...

The injectors will be 2-3 and the resistors should be 9-10.

Why if a resistor box is 6 ohms, does EVERYONE go to Radioshack and get 10 OHM resistors?????

Re: CEL #16
 

Yeah, but there was nothing wrong with the wiring. The box just went to hell.

Re: CEL #16
 

Post that how-to again. Seemed not as easy as the other way.
http://img81.imageshack.us/img81/929...fold093qf8.jpg
http://img81.imageshack.us/img81/816...fold092am4.jpg

Re: CEL #16
 

Because HT told them to. :P

Using 10 ohm resistors will not provide enough current to P/H injectors. This means that they may not open all the way.

Honda uses 6.xx ohm resistor boxes for a reason. This provides the correct current to the injectors.



Go check some OBD0 and 1 boxes. They will be around 6 some ohms.





Also whiterice's setup is the easiest way to add a resistor box. you only have to cut one wire and that is not even on the harness. You only have to move pins around.

Re: CEL #16
 

Thought it was long enough to be there, but I guess not. Damn HD crash. Here are the pics. You just solder the resistor box to the dizzy plug. Leaves stock witing alone and is clean.

http://www.---------------------------/Cray/Rez.jpg
http://www.---------------------------/Cray/Rez1.jpg



I didn't cut any wires, and I didn't have the resistor box plug. I did have a dizzy plug though.

Re: CEL #16
 

I know you're tryin to be all hot with your shrink wrap, but deep inside you know you're having dreams of electrical tape :6

Re: CEL #16
 

I rub one out to the thought of liquid electrical tape. :l

Re: CEL #16
 

There's 8 pins going on that plug but I only see 5 wires from the resistor box. I'm not understanding how this works.
Where does that plug you added to the resistor box go?

btw the cut wire madmax referred to was a spare wire made with 2 pins connecting the power distribution to the resistor box.

Re: CEL #16
 

I dont have to...and Honda-Tech didnt tell them too.

WHY?

Because I know that stock HONDA saturated injectors are 12-13 ohms of resistance across the two pins
I know that stock HONDA peak 'n hold injectors are 2-3 ohms of resistance across the two pins (DSM injectors too)

Then in 1st grade, I leanred math...

I also know that resistance is additive. Add a 3 ohm resistor to a 10 ohm resistor you get 13 ohms...

Re: CEL #16
 

Read what I wrote. NOT ENOUGH CURRENT.

Learning addition won't help you understand that using a 10 ohm resistor will lower the current in the circuit. In a series circuit the current is the same through every resistance. If you increase the resistance, then the current through each resistance will go down.

So using 10 ohms will lower the current through the injectors.

P&H injectors are diesgned to use higher current than Sat injectors. Honda knows this because they know that the strenght of an electromagnet is dependant on the number of turns of wire and the current flow. It also depends on the permeability of the material, but will keep that constant. Now to get a lower resistance in the same space requires less turns or thicker wire (thus reducing resistance). Increasing wire thickness will also reduce the number of turns since the diameter is larger.

Now lowering the resistance has created a weaker electromagnet. What can we do to increase the strength again? Ah yes current. Increasing the current flow will bring the electromagnet strength back up.

This is why you don't match total resistances when using P&H injectors. This is also why Honda resistor boxes are 6 ohms.

Re: CEL #16
 

Thats great and all, but the OBD1 ECUs have injector drivers in them that are designed to run an injector that has a total resistance of 12-13 ohms...if you use a lower total resistance, the increase in current through that circuit will eventually burn that driver out.

This is why it is still possble to run Low Impedence injectors WITHOUT a resistor box...but this WILL burn out the injector drivers.

Re: CEL #16
 

I never said it is okay to run P&H injectors w/o a resistor box. I stated that 10 ohm resistors will not provide enough current to drive P&H injector correctly.

With the honda resistor box of 6 ohms the current output is still way within the operating range of the transistor output. It will not burn out. It would if you ran just a P&H injector, yes.


Go look at the driver spec sheet. The maximun output current of the collector is 6A. With a pulsing input, the max is 10A.

The reason that P&H injectors without resistors burn out the driver's is because of heat. The output current is within spec, but you would need to provide cooling like a heatsink or maybe more. Although running a P&H injector with that much current would burn out the coil.

Re: CEL #16
 

The three four wires carrying 12v are just all going to the red wire on the box. I guess I could have just let them hang.

Re: CEL #16
 

There is only one wire that carries battery voltage. The rest go to other sensors. You need to have those fourwires connected together.

Re: CEL #16
 

well good news, they are all connected.