Truck Issue

[03BlkCobra1]

Ok I have no clue as to what is going on with this truck. When I'm driving it normal the truck is fine as can be. But when I get on the truck around 4,000 rpms it seems to feel like its studdering. I have just recently changed the spark plugs so I know its not one of them (1,000 Miles ago). The fuel filter was changed ruffly 8,000 miles ago. But when the truck is under full throttle it feels like its jerking and doesnt want to go anywhere. My question is whats the odds it could be a coil pack, fuel filter, or something in the exhaust backed up. The reason I include the exhaust option is when I get full throttle the cab of the truck starts to smell like a rotten egg, like most cars do when the cats go out, and it sounds like the exhaust is sputtering, but no check engine light has come on. I'm really confused on what to do since the truck is giving me lots of problems lately.


Thanks,
Paul

 

[Scuba-Matt]

Have you run leaded gas through it? sounds like pluged up cats, coils or bad gas. Your due for a fuel filter change too.

 

[FordFanStan]

Sounds ignition or fuel related to me :shrug: ... Stan

 

[RUthLEss03]

Does this happen when you start getting into boost? Mine is doing the same thing, except I haven't got the rotten egg smell. I'm going to change out my plugs and see if that remedies it.

 

[dirtchicken]

Fuel pump not working maybe.

 

[Lord Tauk]

You shouldn't smell that rotten egg smell should you? Since this isn't a case of the truck being garaged for a while, I'd have to agree.. something could be clogged?

Start cheap, and work from there? Fuel filter, definently change that to a new one.

Correct plugs? Gapped correctly?

No vacuum hoses loose or anything like that? Dunno, just ruling out some easy stuff.

Maybe you filled up with some crappy gas?

 

[03BlkCobra1]

Ok the plugs are new they are the tr6's gapped at .036. Im deffinatly going to do the fuel filter first. As far as normal driving the truck is fine as can be and can even get into slight boost. I normally use the same gas station every time and the problem started at the same time as the rotten egg smell. It starts at ruffly 3800 rpms either wide open throttle or partial throttle no matter wot or standard.. and the vehicle is my daily driver.

 

[BLACKNBLOWN]

Bad cats! IF it was a bad pump you would get knocking also! Its also a good chance you may have a bad coil or to....While you are at it change the coil boots whan changing the plugs, It is like a minin tune up....Run your truck at night if the cats are glowing red or your manifolds it is a good chance the cats are clogged

 

[03BlkCobra1]

One thing I did notice tonight.. It only does it after the truck warms up. If its still partially cool it drives fine.. but once its good and warm it starts to happen.. im still so confused on whats going on.

 

[inuswo]

Changed my boots w/ the last sparkplug change too, Theyre like 3-4 bucks each depending on where you go, worth it.

Im no expert mechanic, but, it doesnt sound to me like a plug or contact problem. Unless your getting misfires etc while in other rpm ranges (or at idle, rough idle etc), I'd personally doubt it to be anything to do with your ignition directly just based on logic.

IMO check out your fuel filter first (if at 8k miles on this one your due in anyways), and while your at it give the hose a good inspection. In my short time of owning an L and browsing whatever information out there that I could find in the last few months about them, I've seen some pretty ugly kinks in the fuel line hoses, even from the factory on new ones. Willing to bet that someone reading this thread will know what picture im talking about when I say 'twisted fuel line'.

Another thing to check would be your MAF sensor, if you havent cleaned the contact lately, go grab some MAF cleaner at an autoparts place and clean it off. You might be getting the right fuel and air, but the computer just cant see it happening, common problem on cars a few years old.

As far as cats choking your exhaust up though? I have no idea about that, like others have said, do the cheap stuff first. Your TR6's come in the box gapped at .035. I put mine in w/ just the chickenears stage 1 gapped at .037 (not much different than yours), but in that same sitting I had the entire top and bottom of the intake cleaned (S/C and all), and the rest of the motor chemical-cleaned through the fuel system. But... just do the easy cheap stuff first & if its still givin ya shit then let everyone here know Someone will have some answers for ya eventually.

 

[03BlkCobra1]

Ok so the fuel filter is ruled out. So im left to the exhaust (cats particularly) or the coil pack. Got it back on the dyno to see if could figure out wtf was going on with it and its still doing it after the filter change. What made me believe was the exhaust agian was the a/f wasn't even reading above a 10 when under throttle (I believe I have that right). So its like its not even getting enough air out to even out the sensor.

 

[Fade 2 Black]

Cats. Might as well get a two cat midpipe and just replace it. Even if it isn't the culprit you'll gain some performance from it.

When the truck is cold crawl under it and rap the cats with a rubber mallet and see if any of them rattle, they may not but I think you nailed it in your first post that the cats are bad.

 

[-00SVT-]

im new but its definately the cats. when i got my truck i thought i bought a lemon because thats exactly wat mine was doing.