2004 Ford 4.6L Triton emissions

Here's the deal: my sister owns a 2004 F-150 with a 4.6L Triton V8. The truck is currently licensed in Indiana, where there is no emissions testing. But she will soon be licensing the truck in Texas, where an emissions test will be required.

If her truck needs any work done in order to pass the emissions test in Texas, she would prefer to do that work while she is still in Indiana, as it would be more convenient and probably less expensive. I will help if some simpler things need to be done. I probably wouldn't tackle a catalytic converter, but would be able to replace sensors, for example.

So my question to the experts: what types of things would be most likely to cause this vehicle to fail a Texas emissions test? Our approach is speculative, we don't know that it would fail. But if there are some obvious things that should be tended to, we would prefer to do that here in Indiana where we have a nice garage to work in.

Anyone familiar with this particular engine and/or the Texas emissions testing procedures? Is the test demanding or an easy pass?

Thanks in advance...
 
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So that will be the first year with cam phasers and they and the timing chain tensioners can cause issues, usually on higher mileage vehicles. They run off the oil pressure and internal seal leaks can cause poor performance and have it sounding like a Diesel. Much less a problem if the right wt. of synthetic oil is used and changed often along with quality OEM or high quality aftermarket oil filters (not cheap red Fram etc) , so I've read on the Forums. Proper driving , like going easy on the engine till it's fully warmed up help too. Continued driving with issues will result in engine failure and the MSG will come up along with the check engine light.

If it is running fine (smooth and quiet) it likely will pass fine, and they can run for several hundred miles! They are a tough engine! If it has low compression in any cylinders it won't run nice and smooth. MPG will go down if there are problems also. Any issues like that will likely make it fail the test.


If you Google the issues I mentioned , you will find the Ford truck forums saying those issues are expensive to fix as the proper Ford Cam Phasers are pricey and the aftermarket ones don't last very long , if they work! The spark plugs can also be an issue to change on those 3 valve engines, so read up a lot to check/change them with the least problems. I have that truck with the 5.4 I bought 2nd hand that suddenly developed the issues after an antilock brake failure on one side stressed the engine. The 4.6L uses the same system, but is less heard of as most trucks were sold with the 5.4L. I'm looking at going back to a 2 valve system or even an older engine as no emissions testing here.

The Cat converters can get plugged up from rust in the exhaust system causing poor running (especially under load) and bucking etc. This can have one thinking it's ignition coils or the transmission!
 
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My sister read some info to me over the phone from her Carfax report. In that report the engine was described as follows:

"4.6L F SOHC 16V"

I assume the "16V" means 2 valves per cylinder? Would that be correct?
 
Is the check engine light on? Not sure about Texas specifics, but many states go on that. If the CEL is on for any emissions-related faults, you fail.

16v is 2 per cyl, the "2 valve" engine. Its the simplest, lowest power, and arguably the least problematic of the family. The only thing with spark plugs is if they are over-tightened. There isn't a load of thread engagement down in the head, so if they get cranked too hard they will self-eject from the block. The fix is a threaded insert to repair the stripped hole. its not that big of a deal.

Don't believe these have the cam phasers either, just the timing chain guides that wear out.
 
Yes! There were 2 of those 4.6L engines , and luckily she has the low powered version! Might it be a 2WD truck? Which body style as Ford experimented by trying Cheap Steel frames on the Cub Cabs from 2004-08 , as they likely figured if Toyota can do it why not them! If that body style check the frame first for rust holes and weakness. It can be replaced with a used later one!

For spark plug thread issues heli coils don't work (they blow out), but solid threaded steel inserts do work to make it as good as new or better.

That's right no cam phasers!
 
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If there is no "check engine" light, or other warning light "on" on the dash, it should probably pass w/o issue. I don't know exactly how TX does their emissions check. Here in PA, they used to use the "sniffer" in the tailpipe, but they have switched to plugging into the ECU for error codes instead. For about $12, you can buy a code reader module on Ebay and download a BluTooth app "Torque" for your phone, and it will read any "error" codes. The most common failure (for any vehicle) on emissions testing are O2 sensors on the exhaust--some have one, many have two, but they are only about $20-40 each, and not hard to replace.

Just saw your post regarding the SOHC 16V engine, so yes, that means 2V per cylinder, as that is a V-8.

If it is running fine, decently maintained, and has no warning lights illuminated on the dash, it should be fine to pass emissions. It is always a good idea to change oil/filter and air filter before getting tested, and a tank of "fresh" gas. I am assuming that it will be driven from IN to TX, so that should not be an issue.
 
Check engine light is not on. And I can do an OBD II check.

It is an XLT. I believe it is 2WD, yes. Nice looking, big. In exceptionally nice condition appearance wise. She says it's a gas hog. But apparently it could be worse as it is the small V8.


Just trying to avoid her failing that emissions test and having to pay a shop big bucks for something that I could fix inexpensively here. She doesn't have anyone in TX that can work on her vehicle. O2 sensors, or other emissions related sensors, I could change. I understand my question is not typical.
 
Thanks for the input guys :thumbsup: Yes, she will be driving it from IN to TX.

Sounds like maybe I should do nothing, assuming an OBD II checks shows no codes.
 
I don't know what the different body styles are. It is a 2-door F-150. Don't think there's a third door, know there are not 4. I have not been inside it :). I will check it out next time I am at Mom's (tomorrow) where the truck is.

What are the possible body styles?
 
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2 door regular cab.

2 door club cab (small rear doors on both sides open to a folding back seat and have no outside door handles on them) and is noticeably longer than the regular cab and it has windows in the rear doors.

The longest cab has 4 full sized doors with 4 door handles , like a 4 door car.
 
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In California where emissions testing is most rigorous and dyno testing was done as well as evaporative system testing on all cars until fairly recently. Now, a car with OB II, 1999 and up is simply a plug in through what amounts to an interface to the state computer which verifies all readiness tests have been passed, no codes are set and the check engine lamp works as intended. The onboard diagnostic system is considered comprehensive enough that if the engine passes it's own ECM tests, the readiness tests and continual monitoring, then it passes. 1998 and older require the dyno testing, at 15 mph and 25 mph... as well as a separate evaporative system test. If your vehicles check engine lamp is working correctly, that is, it lights with key on and goes out when engine starts... and the readiness tests are complete, then it has passed it's own systems check and will pass the Texas emissions test. It even checks converter efficiency, that's what the secondary O2 sensor is for, compares lag time to the front O2 sensor, as well as the evap system. If the check engine light works, goes off when the engine starts, and the readiness tests are complete... you are good to go. The readiness test is the cycle the ECM goes through each time the codes are cleared... scan tool cleared or battery disconnect. The readiness test requires, usually, 25 to 50 miles of driving and often a cold start. If the codes have not recently been cleared in almost all cases the readiness tests will have been completed. I had a close friend in Southern California that had an auto electric shop that did complete smog service and testing. It could became involved and he would pay me to diagnosis problematic systems.
 
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Thanks @spicer. I will do an OBD II check tomorrow, and verify that all warning lights are functional.
Yes... the only one that should matter for the emissions test is the amber check engine lamp. Other warning lamps for other systems that do not also light the check engine lamp will not affect an emissions test. The onboard diagnostics have become quite comprehensive and have been for some time. Good luck with it, sounds like you will have no problems. The amber check engine light is everything to do with an emissions test these days.
 
The check engine light is working. Hooked my OBD II tester to it and it there are no trouble codes.

I was wrong about the body style. Not a 2-door. On both sides in back, it does have the smaller doors without exterior handles . So I guess that makes it a club cab. My sister puts dogs back there so it is convenient for her to have the small back doors.

Thanks everyone :)
 
Tires have tread and replace your wiper blades if they're bad. With no check engine light, you should pass.
 
Sorry it's that model if it was driven in the salt and so best to carefully check the frame to be safe.

Don't be sorry. I appreciate your input. It is great to receive advice from people with knowledge, and even model-specific experience. Several who post here in the AK Wheels, Wings....etc forum are kind enough to share their wisdom and it is very much appreciated.

Don't know about the salt, but probably yeah. I don't think my sister knows much, if anything, about the history of the truck. She got a great deal on it, $5000 I believe, and it looks new, like it should have cost $20k or so. It came from a new car dealership as (I assume) a trade-in, our brother was a manager at that dealership and basically got her a deal for what the dealership had invested. So even if there is a rust problem, she won't be hurt too badly financially.

I will advise my sister of the potential for rust issues. Specifically, where on the frame might rust be most likely to cause problems? And when you said "to be safe"...did you mean literally that safety of the vehicle could be compromised?
 
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