Fuel switching questions.... got the orange "CHECK ENGINE" light came on

[gadget73]

cornholed by ethanol, yeee-haw.

[Hearsesrock427]

Update!

Filled her up with ethanol-free 87 octane, then put in a full can of 44K fuel system cleaner. Ebyt starts a lot faster now- even when cold. Throttle response seems better too. But I still feel the misfiring/cylinders running lean feeling, especially when coasting to a stop. I think it's even more pronounced now than it was before. But couldn't all that just be from the lopo knock? Ebyt definitely has it.

Should I just clear the codes, and then try pulling them again?

[91waggin]

Lopo knock probably isn't going to cause a misfire like that. How old are ignition parts? Mine has leaky valve seals that fouls plugs relatively quickly (10,000 miles), and parts store plug wires sure don't last as long as OEM ones.

[Hearsesrock427]

@91waggin: Ignition parts are unknown age, haha. Which probably means old n' crusty. I'll be cleaning the IAC and TB, soon so I figure I can check out the plugs wires & valve seals while I'm at it. Any particular plugs I should be buying? Any brands to avoid?

[gadget73]

if the ignition parts are old, change those and see what you get. Always do the easy/cheap fix and make sure your basics are good before digging further.

[91waggin]

@91waggin: Ignition parts are unknown age, haha. Which probably means old n' crusty. I'll be cleaning the IAC and TB, soon so I figure I can check out the plugs wires & valve seals while I'm at it. Any particular plugs I should be buying? Any brands to avoid?

Basic standard Motorcraft copper plugs. Gap at .050. Should be less than $2.50 apiece. Don't put anything else in there. Don't let them upsell you to platinum iridium finewire kryptonite blah blah blah. There are all kinds of fancy $12 a pop spark plugs out there that they will try to sell you and I promise you 100% that your 302 will run worse on them than on Motorcraft coppers.
Part # is SP409

I like Ford Racing wires.
http://www.summitracing.com/parts/fm...crown-victoria
But you don't have to buy those; any "premium" wire set will be fine, just don't buy the cheapest crap they try to sell you at the parts house. Same goes for distributor cap and rotor.

I wouldn't check the ignition parts, I would just change them. If you don't know how old they are, it means it's time to do them.

When I bought Clifford (the big red truck), it was misfiring so badly that you couldn't get it above 40mph. I thought for sure there was something really wrong, but I put ignition parts in it just to be sure. That was all it needed. Runs great now.

[gadget73]

The only time I put platinum plugs in, it ran worse. They like boring basic Motorcraft plugs just fine. Most any parts store better grade stuff ought to be fine for the other parts. You don't want the cheap of the cheap, but super duper overpriced stuff won't do anything useful for you either. I like distributor caps with brass contacts too.


The Ford Racing wires are a good value. Good wires, not expensive. I have Taylor SpiroPro on the Towncar because they fit a little nicer with the wire looms I have, but they were like double the price. They look cool but I'm not convinced they run any better.

[Hearsesrock427]

Updates!

I'm using this picture to refer to parts and #s.
http://www.ltdmasta.com/50apart.jpg

I'm trying to remove the upper intake plenum, so I can access the IAC and TB, (as well as enjoy easier access to the spark plugs). I removed the upper manifold cover/faceplate without a hitch (four screws, easy). Then there were two super long bolts, both of which took considerable efforts to remove. Each one came out with a loud CRACK and some smoke from the bottoms. They were toasty, to say the least. I'm assuming that's not how they're supposed to come out. There are 4+ other, smaller bolts (#17 in the linked picture), but I can't fit a wrench down there, even the little one that came with my Craftsman set. There's just too much crap in the way, some of which I've moved, some of which I haven't. Only was able to remove the top nut from the EGR assembly; bottom one is impossible to access with the tools I have. So what now? I'll be hanging out with a buddy of mine tomorrow, and we plan on cleaning the IAC and TB, plus changing the plugs. May even swap injectors while we're there. But we can't do any of this without removing the upper intake plenum.....

In other news, picked up a set of 8 Motorcraft spark plugs. Will order the wires sometime early next week, been busy studying for finals.

[HiFiMerc]

You don't have to remove the upper intake to access the TB and IAC. Or to change the plugs. If you are going to remove it, replace ALL the vacuum lines that are under it. If they've never been replaced, they'll be crap.

A couple end wrenches will get the EGR off. I think it's a 13mm and a 14mm. Or it's a 14mm and a 15mm.

[Hearsesrock427]

Sorry for the delay guys, been busy with school. I finished my last final on the 9th, so I can finally get back to enjoying Ebyt.

Updates!

My buddy and I cleaned the IAC and TB, using some throttle body cleaner. There was definitely some residue and gunk there, and we cleaned it out pretty thoroughly! Fired up Ebyt, and let her warm up for a couple minutes. She idled PERFECTLY! Took a quick trip (~15 minutes) to a local GameCraze, and she continued to idle perfectly. Then out of nowhere, just before we pulled into the parking lot, the idle started surging/bouncing again. What should I be testing/checking? I have a multimeter, so I can see if the IAC is working properly. Although, with only ~74,000 miles, I don't think that's the issue.

In other news, I'll clean and re-gap the spark plugs either tomorrow/today or Monday. If that doesn't make the misfire/stumbling go away, I'll put in new wires and new plugs, and re-gap the plugs.

[slack]

What codes are you getting after cleaning everything?

I cleaned the holy hell out of my IAC and it didn't make a difference. I still get the KOER code. I'm thinking mine is bad but it's not making me stall so it's on the back burner for now.

[Hearsesrock427]

Updates!

Put in a set of 8 new Motorcraft plugs gapped at .50, replacing the crappy, crusty, black-as-a-tire-and-rusted-nicely plugs in the process. She ran 10,000 times better afterward. No stumbling, no misfiring, more power, and just excellence. I now know how a proper running lopo V8 should feel like- smooth and torquey! Drove it around the neighborhood a bit, and then (later) on the highway at high speed to go celebrate. She ran without any stumbling or misfiring. Started her back up a couple hours later. The stumbling and misfire returned. It wasn't quite as profound/bad as before, but it was definitely there. So that means either the misfire is intermittent, or something went wrong soon after changing the spark plugs? FUUUUUUUUUUUUUUUUU

Plans for tomorrow:
-I'll check to make sure the plug wires are securely attached to the plugs (which are presumably, securely socketted in).
-If above fails, I'll verify the plugs are securely socketted in
-If above fails, replace spark plug wires with the set from Ford Racing
-If above fails, test to see if dizzy, cap, and rotor are okay/not fouled or dirty. Not sure how to do this, or what to look for.
-Depending on how the above plan goes, I may/may not need to get a new cap and rotor, plus new dizzy.
-Pull codes again at some point

Then there's the intermittent rough idle. I almost stalled a couple times today. Also enjoyed perfect idle for some periods of time. No discernible pattern. Any place to buy a replacement IAC online? RockAuto part #s?

One last issue. I first thought this was a vaccum leak. See attached picture for more details. I had to nudge this line out of the way to get to the plus on the passenger side. What is the line/what does it go to? I'm leaning toward A/C, but I'm not sure. Seeing as how I plan on deleting the A/C anyhow (need more info on this, namely pics and words), so this isn't a big deal. But it's annoying to hear a whooshing/fluttering sound that increases with RPM.

[TwoTone_90GS]

That line is attached to the air pump system, the metal tube runs behind the engine. To the heads?

[HiFiMerc]

Yup, it runs to the heads. Part of the smog system. That part that stayed on the hose is a check valve. You're pumping exhaust gas into the engine compartment.

Eliminate all that crap if you can. Does it all have to function to pass inspection there?

RockAuto has Motorcraft IAC's for about 63 bucks or so. Don't bother with anything other than Motorcraft.

[Hearsesrock427]

@TwoTone_90GS: Excellent. I'll start gutting it out later today.

@HiFiMerc: Definitely plan on eliminating that stuff; it gets in the way like no other! Plus, pumping exhaust into the engine compartment just sounds baaaaad. Thankfully, Ebyt doesn't need any of that smog pump or air pipe garbage to pass emissions. She's pre OBD II/pre 1996, so she's 100% exempt. I'll order a couple Motorcraft IACs from RockAuto in the meantime!