Well I would double check your connectors and go from there.

You need to hit up Yahiko about his source on diagnostic software.....don't take this wrong but you are going at this blindly. You need to have a good data on what is and isn't going on with the truck. A few hundo on software will go a long way for ya.

 

B0204 in doing a Google search came up with.

1. Could be a Vacuum pump timing error. ??? Don't think the PCM can read that.
2. Could be the B is a P
3. If the B is a P P0204 - Cylinder 4 Injector Circuit Malfunction

I agree with Bismic and Restlesswildman and check connectors to make
sure that they are all seated. The FICM can fool you on that. Both sides
need to click and lock into place. Once you seat it pull back to see if
it holds. You can do it with it installed or you have more work to get at
it other wise.

Sean

 

Arrrgh. I hope not because electrical problems are like a foreign language to me. I bought a cheap voltmeter at Northern tool yesterday and couldn't even figure out how to use the damn thing. It didn't say which position was for AC and which for DC, it just had symbols. I don't know how to test for open circuits or grounds.

I really think that I've just messed something up yesterday - left a wire or connector loose somewhere. It was running good, then died. I replaced the screen and it fired right up like that was the reason it died. Why would all this other crap show up?

 

No work on the oil cooler since I bought the truck in June, about 9k miles ago. Not sure how to get trash in the HPO. I've only replaced injectors, the blue spring, and the fuel pump. I've used OEM filters, but the owner before me didn't - it had an aftermarket cap and gunked up filters when I first changed it. I replaced it with OEM. Heck, I've changed the oil 3x in the last month due to screwing up the injector seal and getting diesel in my oil. Dang oil still looks new after that diesel cleaned out everything.

 

LOL, definitely not taking that wrong. I'm as blind as a bat. I downloaded a couple of different programs - OBDwiz and FORscan - a while back looking for something that would do a cylinder balance, but I never got them working. Also have TorquePro on my phone, but the cheap OBD adapter I waited a month for never seemed to connect - the dang signal lights on it that tell you if it's connected, etc., face the wrong way. By that time, I'd bought the SG and didn't really try to mess with it.

Definitely checking connections first thing tomorrow.

 

Yeah, I searched it too. Definitely saw a B one time, but not again. I think it was supposed to be a P because I got the p0204 error as well, although it only flashed for a second and then changed to p0201.

I bought the SG used off of Ebay, but the vendor had a great rep.

 

Got a good Youtube for you to watch on Volt Meters.
Also known as a DMM, DVM and multi-meter.

It's a long video but as I am watching it as I type I can't
totally say good or not. So far it seams to be a good one.
For more you can just do a search on Youtube for more.


Little better basic one I think



Sean

 

Thx. I think they'd put me to sleep tonight, LOL, but I'll view them tomorrow.

 

Nice links Sean, when you check the FICM connection take a look in the connection it self those little pins will bend, maybe you have a bent pin. and if the clips are broke you can Zip tie them to hold it's always good to add a little dio greese it make them slide right in

 

Agreed. Sean is amazing. Wish the site would let me rep him every day.

 

I did check the pins before I installed, but maybe I bent one installing. We'll find out tomorrow.

 

Sorry for the little
I only wished I could get paid and make a living at it.



Sean

 

Judging from some of the techs I've paid a lot of money to, you could.

 

I've never posted a link, so I just posted this diagram as a picture. There are two other PCM connectors I have not posted. This one is the one that has the ICP in it.


The PCM connector shown above is the middle connector. Pins 2 and 29 go to the ICP. I believe the voltage going to the ICP is Pin 2. The actual return voltage is 29. You can pull the connector and measure Pin 2 on the PCM to see if it has the proper voltage with KOEO. That's either going to be Vred or 0.2V. The return signal should be 0.2V with KOEO, but I don't know how to measure that with the connector unplugged.


You can also hold the positive and negative leads to pins 2 and 29 on the connector (not the PCM side) an measure the voltage and resistance on the harness. There should also be a "short" or "ground" or "continuity" check on the DMM where you can hold one lead on the pin (check both pin 2 and pin 29 separately) and hold the other lead on the negative battery post, to see if you have a short in your ICP wiring. I don't think any ICP wiring should be have a ground. This is the case with most of the wiring. I've done this on the cam and crank wiring, so I know none of neither cam or crank sensor wiring should be grounded.


However, there are a few sensors where one wire is grounded all the time. I know one of the wires to the IPR is grounded all the time. A knowledgeable tech must step in and fill the blanks on this one.


You can do the same thing with the other wiring harness. Once you find something that does not check out, you can check that wiring closely to hopefully find it. It could actually be in the sensor itself.


Check the PCM pin for the correct voltage with KOEO first. If that's not correct, it could be in the PCM or the PCM signal may be getting fouled up by chaffing on another sensor.

There is a special connector you can buy for the ICP that has an additional pigtail to be able to measure the voltages.


You can also disconnect the ICP and measure the voltages at the ICP connector end. They should be the same as those measured at the PCM pins.

 

For wasting y'all's time. This one was user error. Checking the wiring this morning, as I messed with the FICM connections, the connector to #8 injector just came off. I hadn't pushed it in enough. Put it back and the truck runs great again, and all the codes cleared.

My only problems are the IPR -- still stuck in the low 30s at warm idle and never goes below that -- and I'm not getting any ICPV according to SG. IPR seems to work otherwise, never goes to 85 or 15.

Could both of those symptoms result from a bad ICP? I'm going to view Sean's voltmeter vids and figure out how to check ICPv at the sensor. Doesn't it reason that I must be getting some ICPv since the truck and sensors are all working? Could it just be a bad SG x-command setting?

Thanks for everyone's help. If there's ever anything I can do for anyone down here in Houston, please don't hesitate to ask.