5.0 hits a wall when WOT

#21
Update.

Well, couldn't swap on 1993 SSp's coil. Somehow the tip got busted off the coil plug, so i couldn't use it. Unfortunately i found this out after spending 30 mins getting the old coil out.

I used this website, which gave the following procedure to test the coil

TFI TESTING


So i'll be doing that this afternoon. I didn't have a meter with me when i was with the car yesterday

So, i tested the resistances of the TFI and 2 other TFI's i got at the boneyard. My TFI is an A1A type...so i assume it's 21-years old and original. The junkyard TFI i got was an A2A module, so i assume it's newer. I also found a parts store TFI on an '86 GT at the yard.

So, i compared to given values from the website above

So the two motorcraft TFI's i have are higher than the given test values, and the A2A module is slightly lower in resistance than the module on my car.

The aftermarket TFI's numbers are WAY off and significantly lower.

So, i assume if the module was bad, some of these resistance numbers would be way off? I'm kinda thinking of going to advanced...testing the A2A module and trying that out on my car.

I drove the car Sat after cleaning the Accell coil up and reinstalling it. The hesitation above 4000RPM is still there. I watched the tach and it doesn't jump or dance around at all. The car just feels like when it hits 4000, it hesitates, then goes, or hesitates completely to redline. It's def losing some power up top.

I watched my FP gauge and it stayed steady.


PS. The car has never stalled on me nor shut off when it gets hot...so i don't have the normal TFI symptoms. There are no metal shavings or anything inside the dizzy
 
#23
liljoe07 said:
Does the Check Engine Light come on at WOT?

You may wanna check the TPS voltage at WOT....Key on engine off of course...LOL
Click to expand...



Speed density...no CEL. I haven't converted to MAF yet and still need to look how to make the CEL functional once I do that.

No codes last time i checked, but i'm digging around for a test bulb so i can run them again.

Will add checking WOT TPS voltage to my list. My TB is an Explorer 65mm TB with a Mustang TPS modified to fit...so it is possible something has gone bad with it...been a while since I checked it.
 
#24

Sorry forgot it was Speed Density. Any codes that would show the TPS problem would be in the Continuous Memory.
 
#25
This may be a stupid question, but is your smog pump functional? I'd check for clogged cats if it isn't. The fact that your car sat for so many years would also be a red flag to me. I drove a car with clogged cats and the pedal would go to the floor without a change in acceleration, the motor would only get louder, haha. Just one more thing to check off the list I guess...
 
#27


That may be the issue as well.

Stock h-pipe...and no smog pump. I ditched it when i went off-road H-pipe. However, since i needed to smog the car, i swapped the stock pipe back on. My off-road pipe fit like ass, so i never put it back on.

So now i no longer need it for emmissions, but i'd rather put a high-flow catted pipe on...prob get it for Xmas.

Just unsure if i need to put the smog pump back on for the aftermarket QUALITY high-flow pipes. If i do, i'll be looking for a smog pump setup.

Damn, i did a lot of stupid things when i was young...sucks having to undo them.
 
#29


Well the catalyzation process that happens inside the converters requires the presence of oxygen. From my understanding, they clog very quickly without the smog pump attached and functional to supply the necessary outside air. This may be your problem after all.
 
#31
I don't know how aftermarket high flow cats will react to no smog pump, but I do know the stock cats for our cars were designed to work in the presence of the air supplied by the smog pump. The oxygen and nitrogen in the air aids the process by helping to change the hydrocarbons and carbon monoxide to carbon dioxide and H20 (in the form of water vapor).

/science lesson

Good thing is, tons of guys delete their smog pumps, so you'll pick one up cheaply and easily.
 
#32
1991notchbackLX said:
IGood thing is, tons of guys delete their smog pumps, so you'll pick one up cheaply and easily.
Click to expand...


Yeah, i'm gonna put a ad out on the local Mustang board I am on. I'm sure i can find one easily. I need the misc hoses and whatnot...might have to go to the boneyard for that.

I wish i never trashed my original stuff. Now i gotta put the smog pump back on, and the A/C back on.
 
#34
I'm starting to beleive more and more this is the issue. For one thing, i've always wondered why my car doesn't rev as freely as other 5.0's do.

I've asked around and may not need the smog pump for aftermarket high flow cats.

So now i'm stuck debating....FMS P-shorty headers and Magnaflow catted H pipe...or go with a set of long tubes? Downside to LT's is the cost...esp for Ceramic. I really do want to get a ceramic header this time around. My BBK chrome shorties heat-soaked EVERYTHING under the hood. Could always get BBK LT's and install wrap...but it looks like butt.
 
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