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PETEp
06-30-2006, 11:31 AM
:eek: I have a 1990 sc auto, That I dont drive everyday cruise nights, car shows. When I start it up and go about 5 to 10 miles it starts to skip and buck. I will pull over and turn the car off and re start it it runs fine. I have a new crank sensor put in at the ford dealer. The tac,the engine lights do not come on. I put dry gas and fuel inj. cleaner in the gas, and the gas is fresh and high test. There are no codes comming up and it does not skip when I get to the dealer . The car has 90,000 miles it has been taking care of from new, The car looks like new it has never been beat on Thank you for all your help some one must have the same problem:rolleyes: Pete

quick35th
06-30-2006, 11:53 AM
What does it do when its skipping and bucking? Does the tach stop working? Does the upshift light come on? Is the engine heated up by this time?

Shane

95MTSC
06-30-2006, 12:07 PM
Possibly it's sediment in the fuel tank or maybe a clogged fuel filter?

If you could measure your fuel pressure when it's bucking I guess that would tell you whether it's a fuel delivery issue or not.

Merlon
06-30-2006, 12:17 PM
i replaced the fuel filter and ussed sea foam to clean the injectors. worked for 500 miles. dont know if it wazs the gas in my area but everytime it was warm it would skip, and the boost gauge would go to 5psi or more when the mph was barley climbing past 20mph.

check your injectors again, could be a clogged cat, could be the wires or plugs when warm losing spark, could be.

Tickler
06-30-2006, 12:38 PM
Same thing happened to me, it was the crank sensor, even though I had gotten a new one a month back, the mechanic did not gap the sensor, nor did he tie down the wires which the belts quickly ate and caused the problem your describeing.

Might be a good idea to check your balancer / wires / dis.

AnnivSpeCpe
06-30-2006, 12:49 PM
I would be willing to bet it is the DIS module. Replace it and be sure to clean the mounting surface well and use a thin even coat of heat sink grease on the mounting surface. I believe the heat sink grease has dried up allowing the module to heat up. You can try just renewing the grease, but I'm sure the module is fried. Your symtoms are identical to my personal experience. Heat sink grease can be obtained at Radio Shack, or Arctic Silver found at computer supply stores. John

TbirdSCFan
06-30-2006, 05:52 PM
Unplug the cam sensor and see if the problem goes away.. Yes really! :)
It will take multiple tries to start with the key off between tries as the EEC compensates for the missing CID signal and you may get a check engine light and the tach will not move, but don't worry about it. If the problem doesn't come back, replace the cam sensor. :cool:

Jeremy_K
06-30-2006, 07:19 PM
I bet a six pack on cam sensor. My car did the same thing around the same mileage. Start with the cheapest and easiest. $32 at autozone.:cool:

jleopold
07-08-2006, 02:52 AM
Mine was doing the same thing... I started with plugs and wires... never thought about cam sensor... where is that ? --- and is it an easy fix.

rickbtbird
07-08-2006, 05:10 AM
:eek: I have a 1990 sc auto, That I dont drive everyday cruise nights, car shows. When I start it up and go about 5 to 10 miles it starts to skip and buck. I will pull over and turn the car off and re start it it runs fine. I have a new crank sensor put in at the ford dealer. The tac,the engine lights do not come on. I put dry gas and fuel inj. cleaner in the gas, and the gas is fresh and high test. There are no codes comming up and it does not skip when I get to the dealer . The car has 90,000 miles it has been taking care of from new, The car looks like new it has never been beat on Thank you for all your help some one must have the same problem:rolleyes: Pete

I had this kind of an issue last summer and I could not isolate it to any one thing so I tore it down to the heads (including the fuel rails)and starting putting things back one at a time with new seals and gaskets. I also replaced most of the electrical parts and vacuum line as I suspected them. It was a long road but it worked. He's the thread. http://www.sccoa.com/forums/showthread.php?t=65253.
Since you said it does it after 5 to 10 minutes I would suspect the DIS module. Here's a tip if you must replace it. Make sure you use the correct compond when you put the new one on. I've read where Heat Sync compound should be used and other places where Silicon Dielectric Grease should be used. I've tried both and I like the Heat Sync Compound.
Where are you from in Connecticut?

FredSC
07-08-2006, 07:22 AM
Since you said it does it after 5 to 10 minutes I would suspect the DIS module.
I'm with Ricktbird on this if it is so predictable otherwise my guess would be the crank sensor (or crank sensor wire). The "grease" for the DIS is heatsink not dielectric. Radio shack has it. Another brand is "Arctic Silver".

When my crank sensor was going bad (took 3 years of urghhhhhhhhh) it would not restart immediately. Sometimes I would have to sweeeeet talk my SC for 5-15 minutes before it would restart. Promising expensive mods seemed to work for a while (1st year or 2).

When installling the crank sensor on a 90, use a match cover on both sides when setting it. I would get mine adjusted correctly, then would go back and give the 2 bolts their final tightening and the sensor would shift just enough to cause a touching problem. After 4-5 tries I finally used a match cover on both sides and set it the first time. I think the extra match cover provided just enough extra clearance that when I tightened it, it still had the match cover clearance. DEFINITELY, after setting it manually turn the crank through a rotation or two to observe your clearance 1st hand.

Another thing to check is to examine the wire leads going to the sensor, somethings they get pinched or rubbed.

PETEp
07-08-2006, 11:17 AM
HI I am from Middlefield CT, I want to thank every one for all the help. I am getting tired of working on this car. I am keeping it for my son he is 13. I dont drive it a lot the car is like new 97,000. I would sell it if I could get $ 3,000 and look for something else. The re sale even for a nice T bird is low I would have someone that wants real bad.to get 3,000 The car has no mods and never been beat on like I said looks like new. Allways been in a garage from new. thank everyone for the help!:)

Jeremy_K
07-08-2006, 06:56 PM
Am I getting a 6-pack or what? Did you fix it?:D

PETEp
07-09-2006, 08:40 AM
Not yet still skiping:confused:

rickbtbird
07-09-2006, 09:43 AM
Not yet still skiping:confused:
Pete,
Just curious but did this problem happen after the car was worked on? Running for 5-10 minutes is causing something to heat up. So we have to think about what happens after warm up. Check all your igition wires to insure they're on tight. Also, check the exhaust oder after warm up and tell me what it smells like.

Have the plugs and wires even been replaced?

If you can reproduce the problem after a bone cold start then I'd say we have a different problem.

If your problem is electronics, heat could cause them to fail. I suspect the DIS or even the Coil but it's real funny how you're getting no CEL. Bad electronics typically produce some codes.

ThunderDave
07-09-2006, 12:18 PM
Maybe the heatsink for the DIS is bad and it's getting hot.

Merlon
07-09-2006, 01:08 PM
im not sure how. i used sea foam. and also used a better heatsink, called arctic silver 5 from a computer store, way better than a radioshack heat sink grease.

when your injectors are dirty youwill have a starved engine when warm which will produce a lean misfire casuing you not to pass smog test here in cali.

the dis might just be going bad, but if it starts, then maybe your lucky enough where youll only need $10 of heatsink grease to keep it another year.

use the grease directly under it and dont tighten so it all squeezes out. after a few days driving the arctic silver sets. i think it could also be bad gas. when i used bad gas after warm up it would skip in boost. now with high performance gas and 91 i dont have a problem, except for the price.