Engine Miss At Cruise

To answer your questions.

1. The MAF is on the air intake tube right past the air filter.. it has a small wire that goes across ... sometimes it catches dirt and prevents accurate readings. But after owning many cars I have never had that issue.

2. The front 2 O2 sensors are heated while the rear 2 are not... so they are indeed different

3. No you can't clean the O2 sensors.
 
Found the MAF sensor and learned how to clean it. Sounds like it is definately a possability in causing the problem. I'll give it a good cleaning tomorrow and see if it makes any difference. Anyone know what a new MAF goes for price wise?
 
Pulled the MAF sensor out today and sprayed it off real good and it did make a substancial difference but mainly in the idle quality. Can't even feel the thing idle anymore, in or out of gear. That in itself tickles the hell out of me, even if it didn't make a difference in the cruise conditions.
I took it out for a test spin and think it's still missing but ain't sure since the winds blowing pretty hard. If it is still missing I think the next best possability is the 02 sensors. Found some on Ebay for about 15 or 17 bucks awhile back but have no doubt that they're some Tiwanees, Chinese, Cambodian, Yugoslovokyian, import of some kind. Any of you guys have any experience with these low buck options or does most everyone stick with the Ford stuff?
Sill wondering if it could have a weak injector. The miss is at an injectors leanest spray point or condition and if weak might not be doing so properly (just a thought).
Went ahead and yanked out the air silencer while I had it apart and to tell you the truth, didn't notice a whole lot of difference in how loud it is at full throttle. Figured it was going to sound like an old big block with the air cleaner removed.
Still hasn't thrown any codes or displayed any warning messages.
Any other thoughts on this is greatly appreciated. Thanks for all the input so far.

Al
 
It is very hard to diagnose an improper operating injector without adequate equipment. As the matter of fact it is nearly impossible.

If the O2s are old I would suggest throwing some new ones on there... the first 2 are more important so I would start with those. Stick with name brands like BOSCH or OEM ford... I know they are pretty pricy at $40-60 a pop.
 
Thanks Max, I'll give Max at 5-Star a call and order some new ones. Need some other stuff anyway. You know $40.00 ain't all that bad but I had heard that they were about $70.00 a pop. Gets kinda pricy at $70 each. Just got back from Portland and got to go right back out. I'll check in when I get back. I'll try to do alittle more testing on it and let you guys know how it goes. Thanks for all the help.
Al.
 
Finally got to take it out for a test spin since cleaning the MAF sensor and it's still missing, not as bad, but it's still there (idles GREAT though).
Just picked up a 97 LSC dual exhaust system and ain't sure if there are any differences between the Second Gen sensors (part numbers) on the base and LSC dual system. I want to buy the correct OEM Ford sensors for the LSC exhaust. Anyone have the Ford part numbers for both the front and rear 02 sensors for a 97-98 LSC. Thanks.

Al.
 
Well, I got tired of screwing around trying to figure out what was wrong and took it in to have the codes read on professional equipment. Wasn't terribly expensive but worthless none-the-less. Showed no codes and they said they would have to have a bunch more time to figure it out any further.
Read something last week about the spark plugs fouling on a guy after doing the SeaFoam treatment and wondered if that could be it. I had put a new set of plugs in shortly before doing a SeaFoam flush and thought they couldn't be fouled but figured it was worth a try. Bought a new set of APP103s, threw them in and SHAZZAM, NO MISS!
So, if any of you happen to develop a slight misfire after fogging for mosquitoes, try a new set of plugs, it might just save you alot of time trying to trouble shoot it.

Al
 
First, they were the standard copper Autolite plugs. They were a dark red, kind of a rust colored. I hit it pretty hard with the SeaFoam, sucked it up in fairly short order. Wasn't planning it that way, just sorta happened like that.
I'm not thrilled with using the PCV hose to suck the stuff out of the can. Seems to me that it would mostly be concentrated on the drivers side. Maybe that had something to do with it.
If I do it again I'll get a fine mist sprayer and spray it straight into the throttle body looking thing, whatever it is.

Al
 
Whether or not it does or doesn't isn't a concern for me since I won't ever do a SeaFoam treatment in that manner again. Wouldn't have even considered the plugs a possable cause of the problem if I hadn't read of others having fouling happen to them after the SeaFoam treatment.
I tend to believe the more atomized the stuff is, the better the chance of total dispersal throughout the entire engine and cats with a far lesser chance of fouling the plugs if in fact that possability exists. Maybe, maybe not, I don't know. It just the way I plan on doing it in the future.
Who knows, maybe it was just a bad set of plugs. They weren't anything special, just basic copper plugs. Sorta strange though, I've always had excellent luck with any Autolite or Motorcraft product.

Hell, I'm just thrilled to have it running great again, whatever the reason was!!!


Al
 
I did the seafoam treatment to my friends MG once. After we ran the seafoam, we changed the plugs. I think that was a waste, because the seafoam cleaned the plugs like new.:)
 
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