Hey Guys got a question i now all of you have heard. I have no clue on this though. I have a 97 F-150 154,000 on it. The engine is misfireing on the #4 cylinder. I have new plugs, i'm getting good spark, and the fuel injector is opening and closing when suppost to. Any ideas would be a great help.

 

Not to be an ***, but did you search for misfires? This topic has been dicussed in depth many, many thousands of times, and I'm sure that your answer lies in a little research. That being said, if you absolutely cannot find you answer in a search, ask again, begin as specific as possible. Which engine is it? How do you know the injectors are working correctly?

 

If its a 4.6 ide install new plugs and WIRES .

 

If it's a 5.4, swap #4 coil with a known good and see if your misfire changes.

 

I agree start with #4 coil pack.

 

Yes i did do research and everyone talks about #'s 3,6,8 not #4 They all keep refurring to mosture. So let me clarifiy Its a 4.6 with new plugs, Great spark, fuel injector opening and closeing when suppost too. And the misfirer comes and goes comes more often than goes now.
Not to be an *** but there were plenty of post on misfires before you posted about a misfire.

 

What motor do you have? You could check the number 4 coil if you have a 5.4, but a well known issue with the 97' 4.6 is the lower intake manifold gasket leaking water into the cylinders. Often it will manifest itself in the form of an occassional white puff of smoke at startup. That's if your lucky. Otherwise you find out when you spin a bearing and your motor gets toasted. Also on the 5.4 you should check the #7 coil. I had a leak in a heater hose that leaked water down onto that coil and shorted it out.

 

Yeah, I'd never been on a forum before and didn't even know there was such thing as "Search". Have you cleaned the TB? Often the EGR tubes get plugged and cause misfire like symptoms, which can confuse the PCM. Other than that, it could be your wires, or a coil. Even if it looks like a great spark, it may not be enough to light off the fuel. It could also be the intake runner valves. How's the compression? Swap the two coils from side to side and see it the misfire follows.

 

I cleaned the EGR tube and stuff about a year ago. When i had that problem the code was poor air flow EGR. I guess i'm going to change wires. Thanks

 

Any chance that you started using Shell gas? My '02 SCrew started missing about 250 miles after I gassed up at a Shell station. Put in new plugs and swapped #3 & #2 COP's as I had a #3 cyl misfire code present. I once again filled up at a local Shell station and the truck ran good for the first 100 or so miles then started missing worse than ever, but no CEL present and no codes thrown. I decided to just keep driving it until the CEL comes on, but it never did. I then filled up with a tank of Chevron and haven't had the miss since, and that was over a month ago. Maybe coincidence, but who knows. Here in California they use winterized fuel that contains ethanol. Could be Shell is getting something else or their "V-Power" additive is causing problems. You might try another brand of gas (from what you are using) and see if it quits missing.

 

Here is an article that I just found from the American International Automobile Dealers Association:

"Shell gasoline is the latest to meet a new fuel standard meant to ensure engine parts are kept clean.
The voluntary standard called Top Tier is being pushed by automakers BMW, Honda, Toyota and General Motors over concerns about a decline of cleaning additives in gasoline in the past several years. The gasoline is available at all New Orleans-area Shell stations as well as nationwide.

Top Tier is meant to reverse what automakers say has been a roughly 50 percent decline in the use of the additives since the mid- 1990s when the Environmental Protection Agency enacted cleaning additives standards. Auto manufacturers claim the EPA requirements are not sufficient to keep intake valves and fuel injectors free of deposits.

In September, for instance, following the traditional switch by gasoline makers to winter fuels, hundreds of motorists in the Milwaukee area began experiencing fuel injector problems with their automobiles. A Milwaukee Journal Sentinel survey of 298 affected motorists showed nearly half the cars with fuel injector problems had fewer than 70,000 miles and more than 80 percent were 1996 or newer models."

My suspicions may have some validity. Anybody else have confirmed fuel related problems that went away when you switched brands?

 

What is more than likely happening is that you are experiencing the dreaded manifold gaskets on the '97s gone bad and leaking coolant into the cylinder....in particular, cylinder #4!

What can happen if the coolant is not sucked out is HYDRO LOCKING the engine upon startup and throwing a rod, or worse!

As stated above, do a search on HYDRO LOCKED or '97s or gaskets ASAP!!!

Hopefully your problem is not this situation but a bad plug/wire! I have NO idea what these people talking about changing gas are thinking! LMFAO.

I owned a '97 and loved it! My timing chain gasket went bad on my vehicle and cost me a grand!

There are TONS of posts about this subject....just seach for it.

Good luck.

 

I just had a miss fire last week on #7. Turned out to be dirty injectors, after I give up and took it to the lacal ford dealer, all cured and running great! But I only have 126k on mine.