Need help, Engine issue

[CDNBullrid]

I just finished doing the timing chain on my truck. put it all back together and fired it up. Now, it doesnt run on all cylinders. It does run on cylinders 1, 5 and 6. it is good that it runs on cylinder 6 because that kinda eliminates a timing issue. I have swapped coils from a working cyl to a non working cyl. Swapped spark plugs as well. I then removed the intake again to check to see if im getting fuel. one injector was leaking so i replaced that injector. while i was there i did all the orings as well. Put it back together and it did the same thing. I checked to see if the coils were getting voltage. they are. 12v on the first wire, ground on the 3rd wire, and the middle wire is the signal. I checked the signal wire on the running cylinder and it was showing something like 0.2 volts. when i checked the one on the cylinder that was not running, there was no voltage at all. Looked in manual and checked continuity on all the wires right from the ECU to the coil, the wires all had 0ohms resistance, which means the wire is good. What can i do from here. Any ideas would be great. Im not sure where to check from here.

[CDNBullrid]

take guesses, anyone?

[02silverpathy]

Lots of moving parts involved, how about Cam Position sensors? They are prone to failure...did the have to come off or get moved? This may have caused their demise....ground wires and wire connections are super important too as they help finish the ECU's thoughts.

 

What went wrong with your timing chain? Guides?

[jimmycapp]

Sorry I don't have any help, but how much time did it take to do that?

[CDNBullrid]

dont know how much time it took me. spent a few evenings on it. as for why i replaced it, it was making noise, sounded like the chain running loosely over the tensioner or guides. when it was opened up, it didnt look that bad but when held up with the new one, it did sag a bunch more. will see if it is corrected when i get it running properly

 

The cam position sensors were completely removed during the repair. I cleaned them and put them back in. There is no adjustment for them, single bolt, no slot. Could this affect only 1 or 2 cylinders to be firing off the one cam shaft? Ground wires have not been touched so im guessing there is no problem there. However, i did check the ground circuit back to the ECU from each coil and they all test good.

 

thanks for the input

[02silverpathy]

I think I know what sound you are talking about, I have heard a few VQ's go by that sounded like some links were colliding with each other as they were stopped abruptly to go over gears.

 

Good call testing the coils and you're right the sensors are straight forward. I can only think of normal maintenance that I could blame for such behavior..fuel filter, injector cleaner, plugs.

 

1-10 how hard was this work? I have seen the pics of the cam gears and their colored teeth for timing, this seems pretty tough at least compared to a Honda anyway.

[CDNBullrid]

im no automotive mechanic but i am a mechanic on agricultural equipment so ive seen my share of engines apart. I would rate this a 8 just because there is so many components to remove. I had the service manual for it because i downloaded it from the link that someone posted here a while back. Just before you are supposed to pull the front timing chain cover off, it says to remove the mounting bolts for the engine, wrap a sling around it at support it. That way you can remove the engine oil pan. This is not necessary but it would make sealing the timing chain case easier. As for the timing chain replacement itself, its very easy. the links are colored so as long as you can get those links onto the 2 cam gears and the crankshaft gear, put a little paint mark on the gears as to where the links line up. that way you dont have to worry about getting the #1 cylinder at TDC on compression. while i was in there i just replaced everything. cam chains, timing chain, and all guides, followers, and chain tensioner. I dont want to go back in there later. Getting the bolt out of the crank pulley was about the hardest part. You have to remove the starter to get at the ring gear so that you can hold the engine from rotating while trying to loosen the bolt. once the bolt was lose, the pulley came off very easily and without much persuasion. it definately was worth doing myself rather than forking out $2000 that i was quoted on labor alone.