SC feels unsupercharged

SinCitySC

Registered User
I bought a 89 SC around the begining of this year. Everything seemed fine, supercharger sung, car felt powerfull, only a few electric problems. One day someone started revvin on me at a stop light, so when the light turned green I went to take off, but my car seemed like a regular Thunderbird not an SC. I took it to my buddy's auto repair shop, the cars not throwing any codes, supercharger still sings, boost gauge still shows boost, the bypass is not stuck, clutch dosen't feel slippy, and I asked around if it could be my tranny. People tell me, "no, can't be the tranny. it's a stick". The car just seems lame. If anyone thinks they know what it is PLEASE HELP. Any info. would be great.
 
maybe its just the warmer weather the sc looses around 10 horsepower for every 10 degrees warmer it gets mine feels fast in the winter and a lot slower now its getting hot outside or else your cats are getting clogged , or tune up
 
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It was still cold when this started, and I don't have cats. It's a big loss of power ,my car used to peel tires all the way through 2nd and half way through 3rd, now I can't peel out in first. :(
 
Sounds like bad harmonic balancer. Check for abnormal wobble of the balancer. There is a timing shutter wheel on the back of the balancer that tells the EEC the crank position. If the balancer breaks and turns on the crank you will have no codes and if the timing is checked it will still show fine. I had this happen last fall. The car kept loosing power. Pulled the balancer off and it was in two pieces. If had slipped about 12 degrees from TDC. My car had no codes and drove ok just no power under boost. Car ran 17 second 1/4 mile at SC shootout, when the car should be a solid 14 second car.



Jerry
 
plkease post your finding

ive got as 95 with the same problem. how does the balancer seperate into two peices? outer and inner?
 
my sc is doing alot like yours its an aod... it used to burn em off when i stomped on it in first and now it just goes and not very fast:confused:
 
Mine came apart at the snout. The balancer inner and outer was okay, but it snapped into at the section that fits over the crank. The 98 Mustang bolt held though, and it didn't come off.

I removed the balancer, and then had to use a two jaw puller on the crank timing gear to pull the remaining sleeve off.

Jerry
 
Thanks guys, sounds like that could be it. I'll check it out, but if any one thinks it could be something else please post.
 
Same here

I have a 90 and I am experiancing the same problems. Over the last 2 years the boost gauge shows ok, but the is no boost.
 
I looked for a new harmonic balancer but nobody has them not even Ford. Autozone said they sell a pully to eliminate it. Do I need the harmonic balancer or can I buy that pully?
 
www.fordpartsnetwork.com sells Ford OEM parts at a discount. It's not a performance part it's the original replacement.

Do a search for BHJ balancer if you are looking for something better than stock. Expect to pay around $350 without pulley, and you will need a zero balance pulley. You will need to have your factory pulley balanced for use with the BHJ or buy underdrive pulleys. Also the BHJ will have to be honed to fit your crank.

Jerry
 
This sounds a lot like what my car is doing as well. How can you tell without pulling the balancer if it is bad?? Is there a visual cue that can be seen?
 
I talked to the guy at the shop that checked my car out, and he said that if the timing was off that my car would backfire really bad and he would know if the timing was off. So basicly he was telling me that it isn't the vibration damper. What do you think? :confused:
 
Make sure your air cleaners are clean + your maf wires, fuel filter before you get into the expensive parts.
 
Someone told me it could be my EGR valve. I do have a exhaust leak and doesn't the EGR valve hook up to the exhaust. Or could my exhaust leak sound be coming from a intake tube, or a blower case leak? :confused:
 
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SinCitySC said:
I talked to the guy at the shop that checked my car out, and he said that if the timing was off that my car would backfire really bad and he would know if the timing was off. So basicly he was telling me that it isn't the vibration damper. What do you think? :confused:

I would believe someone in this club before I believed a mechanic that didn't know anything about these cars. Sure, cars all operate by the same basic laws, but some things change when you supercharge a car, and obviously all makes use different systems. Anyway, if the guys here are saying they've been where you are at and fixed the problem, I would follow their recommendations. At least pull the harmonic balancer and have a look. That's free. Chances are you need one anyway, even if that isn't the problem. One of the rules I follow is to start with the cheapest and simplest things first. Try changing your fuel filter, check all you intake connections, and anything else that is cheap or free. Eliminating those small things as possible problems gives you a smaller list, plus, let's say you change your fuel filter and that isn't the problem, you still have a new fuel filter in the car. No harm done. For example, I went to start my car this morning and it wouldn't crank. I jumped the starter solenoid and it started. Automatically I ASSUME it is bad, so I go to Pep Boys and buy a new starter solenoid. I put it in in the parking lot and go to start it and it still won't crank. So now I'm thinking, clutch position switch, broken/shorted ignition wire, not enough juice from battery, and so on and so on. After driving home and testing the new and old solenoids I find out they are both good. Finally I found the problem, the connector that slides onto the trigger post on the solenoid isn't making good contact. So i put a new terminal on the wire and attach it with a nut. Started right up. Dumbass!!!! :mad: :rolleyes: Anyway, I wasted 16.00 bucks. So moral of the story, try the easy stuff first. Let us know what you find out. :D
 
I talked to the guy at the shop that checked my car out, and he said that if the timing was off that my car would backfire really bad and he would know if the timing was off.

Sorry, this fella has no idea what he is talking about in relation to an SC. Diagnosing a bad damper can be one of the most difficult things to figure out. I was at the Shootout when Jerry's car was losing power and it ran just fine except it was dog slow. It ran like it was getting no ignition advance whatsoever. It was straining and straining and getting absolutely nowhere. Does your exhaust seem to get extremely hot after you run the car through the gears under boost?
 
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