Feels like it's missing.

Two weeks ago I had the car on the dyno ( 1994 SC auto) and it runs just fine. One week later I go to the track and I notice that under full throttle it seemed to have a miss. It will start at about 3500-4000 rpm and would not let up unless I backed off the gas. It missed so bad a couple times that I could start to feel the car buck. The plugs and wires were changed about a year and a half ago but I think I had some el chepo wires on it so I went to Ford and bought a new set of Motorcraft wires. Well I put them on tonight a went and found a long strech of road and it still misses. I checked one of the plugs while I had the wire off and it looks normal. The gap has not grown on it at all. I used Autolight Plattum Pros on it and they have a 5 year warrenty so I did not replace them. Only other thing I had done to the car between the dyno and the track time was to have the fuel system cleaned which included putting in a new PCV valve. Could they have put in the wrong one? Would that make any difference at all?
I could realy use some help. I've got a ZEX dry kit sitting here I want to install but I'm not putting it on till the car is running right.
Thanks in advance.

Change the fuel filter and if that doesn't fix it, change the plugs.

David

The fuel filter is less than 3 weeks old. I had a new pump ( 255 lph ) and fuel filter installed before I took it to the dyno. I could change the plugs but what a pain to change them and it might not fix the problem. Some people might not have a problem changing the plugs but when your a 6'5" 300lb giant like me, you hands have a hard time reaching in to thoes small places where the plugs are.

I feel your pain Jason. One of mine has the same problem and I have swaped almost every part you can think of from my red sc to the black one and still the same thing. Well off to change the fuel pump that will probly not change a dam thing

Jason my brother...hope we can get ur bird back on its feet soon. I didnt know you had taht ZEX kit laying around...sheesh. Sneaky! Anyways, first things I would do is the plugs. Yeah, its a pain but it could be the culprit. Make sure you use double platinums..motorcraft or autolite, but double platinums and dont forget to check if the new wires came with dialectric grease. As far as the fuel system, well...you changed the pump, got a new filter, cleaned the system, you have pressure so it should flow good. I dont think thats your problem. As for the PVC, you are supposed to use a motorcraft one because they are SC specific. I read a post a while ago saying that the motorcraft one was specially made for the boost of the SC...so other brands would not work as good. Nonetheless, i doubt this is your prob. If its not your plugs, i would do a quick check on the MAF...some people end up with dirt or stuff on teh sample tube which affects their driving...not likely, but its quick and worth a look. If not this, then i would go about checking stuff on the ignition side...make sure cam sensor is positioned correctly and the connector good in there, put new heat compound on teh base of the DIS and make sure it has good ground, coil pack, etc.

If you need help with those plugs let me know man... i know Chris and Randy already offered, but just in case.

Well the plugs that are in it now are Autolite plattum pros. They are a double plattum plug and the one I took out and looked at looks perfectly normal. That cheap PVC valve is the only thing that is realy bothering me as I'm sure they used some cheap off the shelf part and I'm postive that if it is specific to the SC that the oil change joint that put it in did not have the right one. I guess it will be back to Ford to get the right one. Anyone know the part number?

JasonMiller94SC said:

Well the plugs that are in it now are Autolite plattum pros. They are a double plattum plug and the one I took out and looked at looks perfectly normal. That cheap PVC valve is the only thing that is realy bothering me as I'm sure they used some cheap off the shelf part and I'm postive that if it is specific to the SC that the oil change joint that put it in did not have the right one. I guess it will be back to Ford to get the right one. Anyone know the part number?

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I think your kind of skimping on not checking all of the plugs. I know its a p.i.a. but I would sure bite the bullet and try it. I burnt the piss out of one, while the rest looked brand new. The PP's as well, 8months old.
Anyway, good luck