2004 XLS 4.0 SOHC At My Wits End! | Ford Explorer Forums - Serious Explorations

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2004 XLS 4.0 SOHC At My Wits End!

Bobbylew

Member
Joined
April 16, 2014
Messages
40
Reaction score
9
City, State
Pisek, ND
Year, Model & Trim Level
1994 Explorer XLT
I have Bank #1 - Rich and Bank #2 - Lean Codes! ???? P0300, P0301, P0302, P0303, P0316 Codes were corrected by replacing the plug wires and cleaning/gapping the plugs. I have new plugs on hand and will replace them.

I used to think I was fairly savvy at diagnosis, but those days are gone! LOL

I have changed the Intake Plenum Seals, Plug Wires, Cleaned and checked Plug gaps, MAF Sensor, will replace Upstream Oxygen Sensors and PCV Valve and Spark Plugs. SES Light flashes after idling for a relatively short time (about 5 minutes), indicating misfire(s). My SOLUS shows the O2 Sensors are switching, but Short Term Trims are maxing out on Bank 1 toward lean and Bank 2 toward rich. We were discussing (and cussing) it at my buddy's shop and fuel injector "Crud" came up, given the vehicle sitting for so long. This might be an "Ah Ha!".

I finally got it licensed and registered, so got on some hard pavement. Floored it and it seemed pretty darned good for a 4.0 with 125,000 miles. That made me believe the Catalysts are okay. I'll check back pressure when I get it on the hoist.

I'm getting ready to "slug it" with LUCAS Fuel Injector Cleaner and then, discovered that it has no Fuel Pressure Test Port (Grrrr!). Fuel Pressure on my SOLUS shows 39.8 psi. and no injector electrical faults. I guess I'll pull the intake plenum again and remove and clean each injector and replace the O-rings. I have an injector pulser and might give that a try before removing them.

This one sat out in the open, on a concrete slab in Northeastern North Dakota for about 2 years, 6 months and started right up with a new battery and PCM. I immediately filled it with fresh fuel. I have looked for wire "Chew Throughs", since I found a nice "Squirrel Habitat" in the upstream side of the air filter.

After the O2 sensor, Transfer Case and Transmission Service, I'm "detail stripping the interior" and will look for more signs of "damage by residents".

Other than all that, it's a fairly clean vehicle, with little rust. I thought the price was right at $500.00. It is still in the "Good Deal" category, given the market prices I've seen around here.

If anyone has ever had this experience, or has any ideas, I would be very appreciative of what you have.
 



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Since there have been no replies that I have seen, here we go.............

Okay! Here's today's (12/7/2017) update! First, it's colder than heck out there, but my 350,000 BTU Forced Air, Propane Heater (Overkill?) makes it tolerable. I learned my lesson for saving fuel by aiming it at my work area and throttling it back to 125,000, rather than trying to heat the whole blasted 30 x 36 building, which doesn't have the roof insulated yet. I ran out of money for that job.

The injectors have all been cleaned and the top is off the motor. I discovered that the #1 Bank Camshaft is about 15 Crankshaft degrees ahead. That can explain a lot. That is now back at Zero. Tomorrow, the #2 Bank gets it, as soon as I can get the special tool installed. Looks like I have to loosen the Power Steering pump bracket for clearance(Grrrr!. Anyone besides me think that these engines are a pain to work on?) There is no back pressure on either side. The cats are ruled out. All vacuum ports were blocked off after the intake seals were replaced and no signs of vacuum leaks there. When I pulled the fuel rails, the rubber Adapters on Bank #2 all came out with the injectors (Vacuum leak?)! It looks like I'm going to have to chisel the Bank #1 adapters out. I looked at the Ford parts web site and they are back ordered. Sounds to me like there have been issues with those. (Found genuine Motorcraft Adapters on eBay!) That could explain the #2 Bank Too Lean DTC. I'm thinking the cam timing on Bank #1 could be responsible for the Bank #1 Too Rich DTC. When I get the left bank (#2) camshaft "Zeroed" and all the stuff that's been removed to facilitate access to where I need to get, I'll try to provide an update sooner than I did this time.

The Fuel Filter job took most of the day, rather than the approximately 0.7 hr stated! I hate FORD QDs! Somehow, after cleaning the plastic upstream piece of junk with Electronic Cleaner, the QD locking part had some movement and I was able to get that disconnected, just like I knew what I was doing. I decided to give the Spring Lock fitting another try and it came loose after I got the disconnect tool in without problem. Go figure! The original filter was in fine shape but the new one must be finer. LOL

Meanwhile, I have become a Parts Changer! Thanks, Ford! UGH! Of course, this horribly cold weather (15 Above Zero, with 1 or 2 above in the mornings!) doesn't help my mood one bit! I hope this is done before we're in the -20s for daily highs! If it's not done by then, I might become a Chevy lover again! LOL
 






A short update: (12/09/2017)

The camshaft on Bank #1 turned out to be 10 degrees late! I'm not sure how that would affect the too rich DTC, but it was way too far off and certainly would not help satisfy the mixture strategy. The special tools are removed and I'm ready to put followers back and reinstall all the stuff I had to loosen and move aside and the stuff I had to completely remove.

At least, I'm gaining on it!
 






@Bobbylew
How did you get to the RH timing chains? What caused the cam timing to be off by that much? You are measuring crankshaft roitation with a degree-wheel of some kind? Determining valve starting to move using a dial indicator? Eyeballing don't cut it. I'm expecting some similar nonsense out of mine, lucky so far, 160K, biggest problem yet with vehicle was a failed TCC solenoid, and highly aggravating recurring SES for "HO2S Heater Resistance Bank 1 Pos 2". imp
 






Your problems all lie with timing I would say. I just rebuilt my 04 from the ground up and ended up learning a lot more than I thought I knew. If you have it apart I would replace both hydraulic tensioners once you reset timing on both sides. You will need to preset chain tension either with the oem tool or you can make your own by shooting epoxy into your old ones and letting it set up before using . It is very important that the camshaft gear bolts are loose when you install these tensioner tools and once threaded in then tighten crankshaft timing gear bolt, same applies for both sides. Now on the new tensioners it is important to prime them in fresh oil. Plunge them into oil until it gets really hard to push them down anymore. You almost need to submerge tensioner while doing this. Then install to correct torque specs. I had a similar problem before my rebuild and mine ended up being that the main timing chain guide / tensioner had broken. This one is located behind water pump in timing cover housing. The other tensioners I was referring to however are located on outside of engine which is why I would start with those. Bank 1 tensioner is right beside thermostat housing and bank 2 is toward rear of head by firewall but still accessible through wheels well. Hope this helps
 






Also i reset my timing by ( eye balling ) with the help of Allan wrenches put inside small sockets to hold position , and 2 sets of vise grips . I wouldn't recommend this way because it is very easy to mess stuff up just saying it is possible . If you have access to the timing tools I would definitely use them unfortunately I didn't at the time and didn't have 300 dollars to buy them so I had to improvise
 






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