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Drummer
11-03-2010, 07:02 PM
Coming home from work today I decided to give my SC a little red light happy time. Didn't rev it up really, just went ahead smooth at first then floored it and ran through gears to second. The car shuttered and lost power a bit until I got into 3rd. I throttled down on it again and it did it again at the high end of the rpm range for third. Almost acts like it has a governor on it. Ideas?

90turbo1
11-03-2010, 07:06 PM
Timing being pulled?

Drummer
11-03-2010, 07:12 PM
Timing being pulled?
Splain what that means.

fturner
11-03-2010, 09:17 PM
Check your plug wires and plugs.

Fraser

91BLOWNBIRD
11-03-2010, 09:47 PM
fuel pump? or not getting good spark at high RPMs

Drummer
11-03-2010, 10:23 PM
fuel pump? or not getting good spark at high RPMs
Well, the plugs are 2 months old. It acts like a restriction. Not a mechanic so I am not sure.

the-big-e
11-03-2010, 11:17 PM
Clogged cats.....:confused:

sinhumane
11-03-2010, 11:35 PM
plug wires. :)

even if they are new or look new. replace them to be sure. i chased this issue with every other fix in the book to no avail until i replaced my plug wires.

91BLOWNBIRD
11-04-2010, 01:04 AM
you dont need to replace them...just check their ohms...does it do it in every gear? is the bogging violent?

I'm thinking fuel related cause plugs and wires will show weakness at low RPMs too

Mike8675309
11-04-2010, 09:05 AM
Is this a new behavior or is this the first time you've ever driven the car like this? When was the last time it didn't behave like this?

Possible issues:
Low fuel pressure - (dirty fuel filter)
Vac Leak - (boost blowing out a leak)
ignition problem - (bad plug wires, bad plugs, excessive plug gap)

Drummer
11-04-2010, 09:36 AM
Is this a new behavior or is this the first time you've ever driven the car like this? When was the last time it didn't behave like this?

Possible issues:
Low fuel pressure - (dirty fuel filter)
Vac Leak - (boost blowing out a leak)
ignition problem - (bad plug wires, bad plugs, excessive plug gap)
New behavior. Just replaced the oil pan and replaced the plugs and both valve cover gaskets. Also did the motor mounts. I suppose I should have replaced the wires also. I hate buying parts because I think I know what it is. Plug wires (Motorcraft) is what I might do next.

notime
11-04-2010, 01:31 PM
Make sure your plug wires are fully seated on the spark plugs. Years ago I had the same issue after replacing headgaskets. Found the Magnacore plug wire wasn't fully seated. The engine would only stumble under high load.

mywhite89
11-04-2010, 06:35 PM
I had the same problem a few months back and it was a bad coilpack. Only did it on heavy load in higher gears. Rpms did not fluctuate other then the fact that it felt like a sharp misfire so the car stumbled. Its seems to be getting worse before I replaced the coilpack. http://www.sccoa.com/forums/showthread.php?t=116490

Maybe that will help.

Chris

mmathews
11-06-2010, 08:09 PM
Sounds like it could be a fuel filter

Drummer
11-06-2010, 08:26 PM
Sounds like it could be a fuel filter
Wait let me guess....The fuel filter is IN the fuel tank right?

Drummer
11-06-2010, 08:28 PM
I had the same problem a few months back and it was a bad coilpack. Only did it on heavy load in higher gears. Rpms did not fluctuate other then the fact that it felt like a sharp misfire so the car stumbled. Its seems to be getting worse before I replaced the coilpack. http://www.sccoa.com/forums/showthread.php?t=116490

Maybe that will help.

Chris
I think I am going to replace the original wires and the coil pack both. These are both original parts from DOB. Should I get the accell pack or the OEM pack?

mmathews
11-06-2010, 08:40 PM
Fuel filter is inline under the back side of the passenger side door. The in line is a simple remove clip and pull off. I would put a white pan or a pan with a white towel in it and pull the in line off. Catch the gas coming out of the filter on the towel. If its mud or rust colored, replace it. In my experience, thats when they are nearly clogged. It's cheap anyway. If you haven't replaced it yet, i would.

Drummer
11-06-2010, 08:52 PM
Fuel filter is inline under the back side of the passenger side door. The in line is a simple remove clip and pull off. I would put a white pan or a pan with a white towel in it and pull the in line off. Catch the gas coming out of the filter on the towel. If its mud or rust colored, replace it. In my experience, thats when they are nearly clogged. It's cheap anyway. If you haven't replaced it yet, i would.
It's been there since 1989 so I think now would be a good time. Whats in the fuel tank? ANything?

mmathews
11-06-2010, 08:58 PM
The fuel pump

91BLOWNBIRD
11-07-2010, 12:35 AM
always stick with the stock coil pack...and I like the stock plug wores too

Drummer
11-07-2010, 10:11 AM
always stick with the stock coil pack...and I like the stock plug wores too
That's what I thought. I think it's a pain to change plug wires but I guess I will manage. Is the 3.8 SC Coil pack the same as all the other Ford 3.8 coil packs?

sinhumane
11-07-2010, 11:03 AM
do wires first. you can always do a coil pack later. there is no good reason why your coil pack shouldnt outlast your vehicle. :)

Drummer
11-07-2010, 11:13 AM
do wires first. you can always do a coil pack later. there is no good reason why your coil pack shouldnt outlast your vehicle. :)
Yes sir........

BlackbirdSc94
11-07-2010, 02:55 PM
Id do the fuel filter first though, 10 buck and 10-15 mins to change if that, make sure you de-pressurize the lines first thought. Im putting my .2 cents on it being the filter. Does the car run fine for like 2 mintues in the morning before it starts doing that???

Itll run fine until it eats up the fuel after the filter then it starts starving for fuel

Drummer
11-07-2010, 04:17 PM
Id do the fuel filter first though, 10 buck and 10-15 mins to change if that, make sure you de-pressurize the lines first thought. Im putting my .2 cents on it being the filter. Does the car run fine for like 2 mintues in the morning before it starts doing that???

Itll run fine until it eats up the fuel after the filter then it starts starving for fuel
Haven't really paid attention to it like that. As far as the pressure in the fuel line goes, how do you let the pressure off or should i just take it somewhere to get this done. I picked the most challenging car to get and still can barely figure out which side the gas goes into.

Mike8675309
11-07-2010, 07:02 PM
there is a fitting on the fuel rail near the drivers side front of the blower above the drivers valve cover. It may have a plastic cap on it. with the key off, take the plastic cover off. then wrap a paper towel around the valve and put on safety glasses. use something to press the valve tip open looking away so that the pressure can be relieved. Some fuel will come out.

Drummer
11-07-2010, 07:13 PM
there is a fitting on the fuel rail near the drivers side front of the blower above the drivers valve cover. It may have a plastic cap on it. with the key off, take the plastic cover off. then wrap a paper towel around the valve and put on safety glasses. use something to press the valve tip open looking away so that the pressure can be relieved. Some fuel will come out.

When you are done putting the fuel filter on will it repressurise?

Mike8675309
11-07-2010, 08:33 PM
When you are done putting the fuel filter on will it repressurise?

Once the fuel filter is replaced, and everything is buttoned back up, you can turn on the key and try to start the car. It will not start up right away as air is purged from the fuel system, but then it will build pressure. If you just turn the key on, but don't start the motor, pressure will build, but air won't necessarily be purged fully.

Drummer
11-07-2010, 09:23 PM
Once the fuel filter is replaced, and everything is buttoned back up, you can turn on the key and try to start the car. It will not start up right away as air is purged from the fuel system, but then it will build pressure. If you just turn the key on, but don't start the motor, pressure will build, but air won't necessarily be purged fully.
Very good. I will get the filter and plug wires tomorrow (Stock) and get this done. Thank You Sir.

BlackbirdSc94
11-10-2010, 02:52 PM
So howd it go, and on a side note Id again do the fuel filter first and if it fixes your problem you can take the wires back unless you just want to replace them anyway but still do one first and check to see if it fixed the problem. That way youll know what was causing the issue incase it happens again later, if you havnt done it already I would use a old rag to put over the valve before you relive the pressure and use a small screwdriver to push the valve down, might just blow through a paper towl.

Also cycle the key on and back off a few times(it helps to have someone else cycle the keey) and check the filter and make sure its not leaking

Safety first ;)

Drummer
11-10-2010, 08:04 PM
So howd it go, and on a side note Id again do the fuel filter first and if it fixes your problem you can take the wires back unless you just want to replace them anyway but still do one first and check to see if it fixed the problem. That way youll know what was causing the issue incase it happens again later, if you havnt done it already I would use a old rag to put over the valve before you relive the pressure and use a small screwdriver to push the valve down, might just blow through a paper towl.

Also cycle the key on and back off a few times(it helps to have someone else cycle the keey) and check the filter and make sure its not leaking

Safety first ;)
Ordered the Bosch plug wires today at Autozone. They should be in tomorrow. As for the fuel filter I think I am going to try to tackle this on Saturday. My garage is full of SH&^T and I am not going to do this in the dark or with a drop light. I printed out the "How to" on the fuel filter and will follow your instruction.

mmathews
11-10-2010, 11:39 PM
get a headlamp! anyone that does anything with their hands, in the dark, should own one

Drummer
11-10-2010, 11:43 PM
get a headlamp! anyone that does anything with their hands, in the dark, should own one
Got one. Railroad issue.

David Neibert
11-11-2010, 04:56 PM
You may also want to look at the fuel pressure regulator and make sure the vacuum/boost refrence hose hasn't fallen off the regulator or where it attaches to the return plenum. What you are describing sounds more like a fuel delivery problem than an ignition problem.

You can also go to autozone and rent a fuel pressure test gauge (for free), and do a pressure test that will tell you if there is a problem.

David

PS: Seem to recall people having problems with Bosch wires or plugs...might want to do a search on that before installing them.

90coug
11-11-2010, 05:24 PM
get a headlamp! anyone that does anything with their hands, in the dark, should own one

:rolleyes:

Drummer
11-14-2010, 02:41 PM
You may also want to look at the fuel pressure regulator and make sure the vacuum/boost refrence hose hasn't fallen off the regulator or where it attaches to the return plenum. What you are describing sounds more like a fuel delivery problem than an ignition problem.

You can also go to autozone and rent a fuel pressure test gauge (for free), and do a pressure test that will tell you if there is a problem.

David

PS: Seem to recall people having problems with Bosch wires or plugs...might want to do a search on that before installing them.
Fuel pressure regulator hose is on. Didn't do the pressure test though, might do that Monday. The plug wires seem to be doing fine. Did that in about an hour. Happy to say I drew ZERO blood in the process.

Drummer
11-14-2010, 02:47 PM
So howd it go, and on a side note Id again do the fuel filter first and if it fixes your problem you can take the wires back unless you just want to replace them anyway but still do one first and check to see if it fixed the problem. That way youll know what was causing the issue incase it happens again later, if you havnt done it already I would use a old rag to put over the valve before you relive the pressure and use a small screwdriver to push the valve down, might just blow through a paper towl.

Also cycle the key on and back off a few times(it helps to have someone else cycle the keey) and check the filter and make sure its not leaking

Safety first ;)
Just finished the plug wires with not to much issue. Seems to idle better but that might be psychological. Haven't gotten to the fuel filter yet. I know I might be off and this really isn't the problem but these are preventative maintenance things anyway so that's a plus. Even if this doesn't solve the problem at least I know I have new plugs, plug wires and a new fuel filter so if anything else gets stupid at least I can rule those things out. I am very proud, not a cut or a scratch. No blood letting on this project. Might be a first from what I have read. Follow up after the fuel filter and a trip to Autozone to let them check fuel pressure.

Drummer
11-16-2010, 10:06 PM
Fuel filter changed. Seems to run better it just wants to cut out at the high end of the rpm's. Just before red line it stutters. So now what?

fturner
11-16-2010, 10:15 PM
My grand daddy always told me that if you didn't let some blood on the job you didn't do it right.........

Fraser

Drummer
11-16-2010, 10:27 PM
My grand daddy always told me that if you didn't let some blood on the job you didn't do it right.........

Fraser
So if I bleed on the car will it act right? LOL

Pablo94SC
11-17-2010, 12:45 AM
Breaking up on the top end... hmmm. Have you tried pulling the codes yet to see if you have any stored?

mmathews
11-17-2010, 12:56 AM
What octane are you running?

sinhumane
11-17-2010, 01:33 AM
hm, have you pressurized your intake to check for vac leaks yet? if you have egr, the edpe valve could have leaky hoses (that was a big leak on my 95.)

also check the sc bypass vac line.

decipha
11-17-2010, 02:20 AM
if its sputtering and breaking up its probably lean

if its cutting out and loosing power its probably the coil

listen for detonation and make sure your not floating the valves