I replaced the timing chain, tensioners and guides on my truck and now after getting everything back together the truck is running pretty rough, and has a miss. For the most part the truck at idle seems fine, but when in higher RPMs it runs rough and does not have the power it used to. From what I can tell it seems like there is a slight tick/noise coming from the top end as well. I did get a code for bank 1 lean(dont remember exact number). I ran a leakdown test on a few cylinders and has 0%-5% leak on the ones tested. Did a compression test on all cylinders, passenger side was 140-155 and driver side was 150-170. With the truck running if I unplug the fuel injector for 3 cylinder back on the passenger side there is hardly a noticeable difference, so I also tried just swapping coils between a couple and that did not change anything.

I am wondering if anyone has some ideas of where i can go next... Is it possible that my timing is a little off and that is causing the issue? Did one of my fuel injectors take a crap? Would I have a slight tick if it was a bad injector?

Any suggestions and help is greatly appreciated!

 

Wild guessing, but with the difference in the compression from side to side, it does make a person wonder if the timing is off on one side. It could be either side. Some time back a guy posted a problem with his 4.2 V6 that was running rough. It had abnormally high compression and it turned out that the woodruff key on his harmonic balancer had worn the groove in the balancer much wider than it should and the timing was thrown off.

 

Ok, that is kind of what I was figuring was the case. But just wanted to make sure before i tear it all apart again. So as far as setting the chains all i can really find information on is the 3 valve motors... The aftermarket chains i got have 2 black links on 1 side and 1 on the other. Does the 2 black links go over the timing mark on the cam gear and the single link goes on the timing mark on the crank gear?

 

Read this thread:

https://www.f150online.com/forums/ar...r-engines.html

 

Don't loose faith in your ability to correctly time it just yet.

A fairly major 'giggling' of lots of stuff under the hood often leads to 'ump-teen' bazar / overlapping symptoms causing doubt about our having done a repair correctly. It seems this may be where you are, based on the following reasoning: 1) I do not think you would be saying "idle seems fine" if timing is off. 2) lean codes are very often the result of a vacuum leak - possibly something disturbed or not reconnected / reseated completely. 3) lots of electrical connectors (CKP,CPS sensors) have been unseated / reseated - any one of which could be causing 'some' of your crazy symptoms 4) injector taking a crap would require (unlikely) time coincident failure.

Finally, I do not know what all parts were replaced, but a battery disconnect and a bunch of new parts mixed in with existing parts can leave the PCM's little brain all screwed up on its adjustment tables. It can take several drive cycles (some exceeding 60 mph) for the PCM to relearn and rebuild all its adjustment parameters. If you haven't tried this (simple & inexpensive) procedure, I recommend trying a battery disconnect "Relearn" procedure to force the PCM to start proper reconstruction of fuel trims and other fine tuning parameters.

As for the miss-fire... It sounds like you have a code reader - If a code is set, freeze frame data and MODE $06 TEST DATA can prove invaluable in sorting it out (see pages 10-12 if 95 of linked doc).

A bunch of relevant / useful info concerning this is found at the bottom of page 9 of 95 through page 12 of 95 in the Motorcraft OBDII Theory Manuel for your engine located here: http://www.motorcraftservice.com/vdi...f/obdsm307.pdf

Hope this helps calm things down.

 

Well I ended up pulling the truck apart again and reset the chains like the link above. All back together and is running A LOT better!. Now I have a pretty bad exhaust leak. GRRRR. The leak is almost non existant at idle and is quite bad when actually driving. The only thing I can think of is my new EGR tube is just not sealing up. Dont know if the new tube I got is just bad or if the leak is coming from somewhere else. What is the best way to track down an exact spot of the exhaust leak? Just use a tube up to your ear?

 

Sounds redneck'ish, but hook your shop vac hose up to its discharge side and duck tape the hose to the tail pipe. Then spray soapy water everywhere and watch for bubbles.