Information on missing under boost?

Michael Mattix

SCCoA Member
Everyone,
After doing a search for my problem with no luck (I don't have a whole lot of time for searching posts), I am asking for help on which choice of words I should be searching for to find information on my problem. The problem is under all PSI's of boost my car stutters/has no power/misses/etc. (I don't really know what to call it). It's just so frustrating to do a job yourself to get the satisfaction and save some $ on labor and have problems when you "think" you are done. I figure it has got to be something I did because I just got done changing the following:

Plugs: Autolite APP2544 (I think) (Got them from SCP)
Wires: Magnecor 8.5mm (SCP)
Idler pullies: (SCP)
Intercooler gaskets: (Tbird88)
Radiator: (radiatorexpress.com)

Thanks,
Mike

P.S. For all you people who are able to change their plugs faster than 20-25 hours, I hate you! Just kidding. Granted, if I were to do it again, I'm sure I could do it faster. I am just venting from going through the experience the first time. I should have paid my trusted mechanic to do it (banging head on the desk)!
 
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Hey Micheal Mattix

I going to take a guess here and say fuel delivery problems.... You need to check your fuel pressure at the rail... Could be weak fuel pump cloged fuel filter bad fuel pressure regulator...Do you have the right size injectors on the car maybe bad injector or two ... Lack of fuel under boost can reak havoc under boost... If it runs good with out boost and there are no codes it has to be fuel problems seeing that you have changed plugs and wires.. Start up fuel pressure should be 38 to 42 at the rail after it has started it should fall to around 32 then for every pound of boost it should rise and max around 43 to 45.

We have a real problem in this country with bad gas additives some are claiming that their gas is high octane with ethanol in it and it is not if it has ethanol in it you shouldn't use it in a good running SC it (ethanol) will cause problems...
 
Thanks stocker,
But, my SC was running fine (in boost also) before I did plugs and wires, so I am 99% sure that it's probably plugs and wires or something that I bumped into or removed and didn't reinstall. I was just wondering what search words are the best for finding this problem. More than likely, someone has posted here about that but, I'm having a hard time finding the info.
 
Michael Mattix said:
Thanks stocker,
But, my SC was running fine (in boost also) before I did plugs and wires, so I am 99% sure that it's probably plugs and wires or something that I bumped into or removed and didn't reinstall. I was just wondering what search words are the best for finding this problem. More than likely, someone has posted here about that but, I'm having a hard time finding the info.

I had the same problem also. I ended up changing the plugs and the wires. I ran the stock plugs and gaped mine at .050. Works great now.

But if you do that, and still have the problem, do look into the fuel system. Something bmaybe clogged or going out.
 
Ohh well then you should have some codes...

If a plug is not firing or plug wires are bad.... The EEC will identify wich plug and or plugs are bad or not firing and throw a code.... I too have the same plugs as you.... I gap them at .50 like forcefed95sc does ... Good Luck
 
Well, I don't have many mods (yet), I gapped mine at .054. Do you think that's bad? The range in my service manual was .052 - .056.
 
michael mattix, man im having the same problem as we speak and its killing me. I have had 3 mechanics look at it and everybody has the same damn answer "HMMMMMM I DON'T KNOW??" wanna talk about frustrating you mean to tell me you get paid 75 dollars an hour and you can't figure it out??? i have been trying to figure this out for 4 months :mad: . the only thing i have not done yet is plugs and wires which are getting done sunday. so if you get anymore info please let me know cause im real close to dropping it off at the junk yard and calling it a day!!!!!!!!
 
Yeah, I know what you mean debo!

I was just doing more research and saw something that you weren't supposed to gap double platinums! Oops! Most of my plugs came out of the box within the range, but I remember opening one up a little bit because it was too small of a gap. And I've heard that the round "half dollar" looking gapper is not good to use. Another oops! Maybe I should switch them back to Motorcrafts. Most people on here seem to have had great luck with Autolite's. I guess not me. We'll see what my trusted mechanic says tonight.
 
i've heard about people having good luck w/those too but i have also heard about people having even better luck w/ the motorcraft or getting more boost w/ denso plugs. see my problem started when i had headers and my valve cover gaskets done so sunday im putting plugs wires and coil pack to see if it will fix it hopefully.
 
anytime i ever had missing problems it was plugs or wires one time i put plugs in and wires where bad and ruined new plugs in about 2 months when other sensors went bad or fuel pump went car would quit completely then restart like crank sensor
 
I had the exact same problem when I put Magnacor wires on I dunno why some peeps on here have no prob with them. Went back to ford parts and miss went away....Autolite plugs S/B ok though with that gap. If memory serves I gapped @ .052 on my motorcrafts since thats where the problem began thats where I'd start just my .02

Rick in FL :cool:
 
Also make sure the plug wires are on all the way. I know when I did mine, It would take me a minute to find out if it is snapping on there or not. If in doubt, try again. Unless you just like jacking the car up and doing it again.

I am not using the motorcraft wires, I have the borg warner from pep boys. $37 and lifetime warrenty.
 
Just one...

It only takes one cracked plug, or slightly bad wire and this car can run like total crap.
I've experienced both scenarious. It idled fine but under boost it just coughed. Once was a plug wire that was not totoally conected. The car was not throwing any codes. Even the weak cylinder test was all good. Not till I went in to replace them did I find it.

I recently replaced my plugs after during a head job and I cracked one the new plugs when putting them in. Of course I found this out the hard way.

I know it sounds sick, but you may want methodically replace each plug and wire one at a time until you figure it out. Or do the three easy ones and see what happens... You'll get faster at it.

good luck
Bob
 
Michael,

I'm certian the problem has to do with the plug wires. If you used a Haynes manual to determine where each wire belongs...it's wrong and the car will run just as you described.

Follow this diagram and check that each wire is in the correct position and properly seated onto the plug. The Haynes manual has an error on the coil pack numbering and it has screwed up several people in the past (including me).

PlugandWireLayout.jpg


David
 
Thanks to everyone for a reply!

David:
Unfortunately for me (because I want my car fixed), I do know about that problem and I have a hard copy of the Ford Service Manual from Helms that I used. To steer clear of having that problem, I changed them out one at a time. I checked how the Magnecors were installed this morning against the manual, but they seemed to be correct. Just this morning, I changed my plug wires back to the original Motorcraft ones to see if the wires were the culprit. No luck. I guess that I could have still not got the wire on enough, but I don't know how I would get it on any better unless the engine was out! Having done it once has sped it up SO much! So either I have a bad plug, or I gapped it incorrectly. I am going to try and procure some motorcraft ones. If the problem still persists, I am going to tackle my intercooler tube connections. I just installed tbird88's gaskets and was looking at each connection. One of them doesn't look "perfectly" parallel, so I'll mess with that. Other than the dealer, does anyone know where I can get AWSF34PP's? I checked Autozone yesterday and they can't even get them anymore and tried to sell me some champions (no thanks).
 
Mike,

With the engine running start pulling wires off the coil pack one at a time, to see if you can isolate which clyinder is giving you the problem. Might have one cracked/bad plug.

David
 
Yeah, David, that sounds like a good idea. I was also thinking about running the cylinder test thingamabob with the code reader. Maybe that will point me to the bad plug/circuit? Anyway, if that shows up nothing, then I'm certain that I didn't install the intercooler tubes correctly. I used Tbird's gaskets, but maybe the order that I used (per the Ford service manual) wasn't the right way to do it or maybe I didn't understand it correctly. Now that I'm thinking about it, I am going to loosen all attachment points and ends and then (in some certain order, probably the lower one first) tighten the ends to the intercooler and engine first. Then tighten the attachment points (I did end up deleting the useless lower intercooler tube to engine block bracket). I am almost certain that I did tighten them correctly. If memory serves me, I left the lower intercooler tube (intercooler was still removed) attached, but loose, to the power steering pump. Then I aligned it with the intake manifold attachment point. I evenly torqued each side down until 25Nm (I think). Then I tightened the lower attachment point at the power steering pump. I then installed the intercooler (loosely) to the rubber boot (no attaching to the upper or lower intercooler tubes yet). I grabbed the upper intercooler tube and test fit it to see how I was going to get it on without messing up the RTV once I applied the bead. I then applied a thin bead to the supercharger. Then I installed the upper intercooler tube (assembly) and torqued down the supercharger top bolts evenly to 20 Nm (I think). Then I installed the lower tube connection to the intercooler. Finally, then I attached the upper intercooler tube to intercooler. A leak in those tubes might cause the same thing, right?
 
yeah that could do that but as bad as it sounds you need to check all the plugs and wires because i had 1 cracked plug that i wouldn't even seen and that fixed my whole problem. needless to say i blew an oil cooler line on the way home so the pos is broke down again :mad: oh yeah by the way the guy i had do my plugs and wires had the off and back on in 45 minutes :p unbelivable!!!!
 
The joy of high performance wires...

ALthough you used magnecore wires, I've run into this situation too.

I ordered up a set of Jacob's Electronics Ceramic Boot spark plug wires and Motorcraft plugs (by the way, Autolite manufactures Motorcraft plugs I'm pretty sure).

I put everything in, properly gapped. I made sure to use a beam gapper and not a circle one.

The car started right up and sounded strong. I drove it away and everything was great. When I took it into boost was when I was having problems. Like the whole engine was kicking in and out on me.

So, After checking all of the connections, I sent the 1st set of wires back to jacobs and recieved a 2nd set. I put the original wires back on and everything was fine. I put the 2nd set of jacob's wires on and the problem returned.

I consulted with Jacob's tech help and they suggested that I undergap the plugs. I spent the whole day R+R plugs to gap them .005" at a time. I ended up with a gap of .035" where it wasn't cutting in and out any more.

I've run the car that way since and I really haven't had any problems. I still have never been able to figure out why the Jacob's wires neccesitate a smaller spark plug gap though.
 
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