Okay so I do have a few threads about my truck having a popping and sputtering sound, with the engine code saying that my truck is running to lean on bank 2. This only happens under a load.

I took my truck to a guy I had heard was pretty good with Fords. He without even looking and just hearing my problem immediately said it was the intake gasket, and it was throwing air in on top the valves and causing the truck to get to much air, and not enough fuel.

What are the chances he is right? Is this a common issue with the Triton 5.4L? He said it was. He also said it would be 240 bucks for the labor and him putting the new intake gasket in. I think that sounds great. I just wanna know since he didn't even look at it, how common this is, and if it were just leaking in one spot this would cause this? It does happen under a load, ONLY. So the truck has to be in drive. The Catalytic convert isn't stopped up it had the right amount of preasure when I had it tested. This issue has been bugging me for along time.

 

A compression test and leakdown test will tell you what is really going on.

 

Sounds like bunk to me, ask him if he will stand by his work and refund the money if it doesn't fix the problem.

 

Well I went out and wheeled around in the mud not willingly but because of where I was hunting before the rain hit it got bad wet and muddy. So I ended up having to give her hell getting out. Everytime when I was in 2WD mainly I'd give her hell the wrench would come on and the truck would run like ****. If I turn it off it'd run great. Soon as I fired it back up it'd go away, and be running great. I still haven't gotten a good answer.

What are the chances it is the intake gasket that is leaking? This guy is not someone who would screw me as I said I know him pretty well. Hes a good ford mechanic. I just had my doubts of him just diagnosing it without even hearing it. Just me telling him about it was enough for him to tell me it would be the intake gasket, and that hes seen a few of these trucks come into his shop with similar issues. Mine is under a load, and between certain RPM rev's and it pops and sputters and doesn't wanna run very good.

 

A lean code could be a intake gasket leak or maybe a vacuum leak or it could be as simple as an old fuel filter. Most mechanics don't want to diagnose things over the phone.

 

I talked to him face to face. Fuel Filter is brand new. Its only on one bank, and its defiantly popping and sputtering under hard acceleration. I will inspect it for a vacuum leak.

 

I guess it just sounds funny that he didn't look at it to me. As far as it being a common issue I don't know but I've not seen anything on these boards about it. Is it idling rough? If it was a leak I'm thinking it would be worse at high vacuum conditions such as when the throttle is closed. Do you have a scan tool? If you could look at the O2 PIDS that might tell you if a sensor seems out of whack.

 

No it idles great. In fact you can rev it to 5 grand without issue in park. Soon as its put into gear it, and floor it I get the missing, hesitation. Which has in the past thrown a code or two. The first code it ever through was Cylinder 8 misfire. The second code was "System to Lean: Bank 2". Then the next code was "Misfire detected within first thousand RPM Revs. It hasn't been as bad lately, but I took it out wheeling again not entirely on purpose, and when I had to give it hell I got the wrench light that would come on.

The entire time it would come on it would make the truck run very poor. Almost like it was in safe mode. I turn the truck off and back on and its gone. Then the engine light has been on now and stayed on. The code I got was P2106 which has something to do with the "Throttle Actuator Control System, Forced Limited Power" which is exactly what seems to happen when the truck goes into this safe mode. Again this to me is probably because I was hard reving it in 2WD through the mud. It didn't do it in 4WD that I noted.

Again I think this may be unrelated. However the light engine light is on, and has been staying on since that mudding incident. I had my spark plugs replaced at the dealer. What is odd about the whole situation, is that I paid a lot of money to get it done. None of them had a clue how many plugs broke off. In fact my truck was sitting in the same spot I parked it, and it still had the service tag in it, which to me is odd considering they usually wash and clean the vehicles and removed the service tag, so I dk if the plugs were replaced or not, but honestly would fouled plugs cause this? I mean really if the plugs were the issue why did it ever blow a system to lean code?

 

Try checking your coil packs too. I had similar issues on my 4.6 and one of the packs had popped off the plug.

 

Well I'm afraid I'm giving advice when I shouldn't but since I started here goes. The PCM sets misfires by looking at the RPM. It correlates RPM abnormalities with firing position. My experience is that it is not very sensitive and requires a pretty severe misfire to set a code. The lean code would be, I think, based on the O2 sensor signal. Too much oxygen in the stream would mean it's lean. If it's not firing the oxygen isn't burning so it could set a lean code. I would think that would also result in high cat temps.

If there is a vacuum leak there is too much oxygen for the fuel to burn which would also set a lean code. But it doesn't seem to fit with the description you provided. With it happening under loaded conditions it makes me think it is a fuel delivery problem.

It seems like most of the problems you read about in this forum come down to fuel or spark.

 

Like I said I haven't been able to get the pcm to say theres a lean condition again. My ranger did this with a weak fuel pump HOWEVER, it was on both banks. Both bank 1 & 2 were the issue on it, and the fuel pump went out shortly after. The problem went away completely after a new fuel pump was installed. If its a fuel delievery issue it would more then likely be the fuel rail maybe? I was told there is a fuel pump regulator? I am unsure if its on both sides for each set of 4 plugs? Or if its one regulator for all 8, and if it is then it doesn't make since that only cylinder 7 and 8 are the ones misfiring... or at least thats the only ones that have ever shown up on the PCM.

 

I guess I didn't appreciate the fact that the lean code wasn't replicating. And I agree if it was the fuel pump or regulator it should affect both banks. I suppose it could be an injector or something specific to bank two.

When I was having hesitation problems I would get misfire counts but it only set a code once. I also got a TPS codes. Other funny things would happen with some of the OBDII signals during the miss as well. I changed the plugs and all was fine. How long after the plugs were changed did this start? Can you pull a couple from Bank 2 to check them out and check part numbers?

Were you able to check for a vacuum leak?

 

find a shop that has the ability to 'smoke' test the intake system to attempt to eliminate the vacuum leak.