i know we do ford trucks here but i need to get the wifes car running right again befor i can do anything else to my truck. heres the deal. tonight on the way to the mall the car started acting funny. at highway speeds the engine felt like it was mis-fireing.and the chack engine light started flashing. it only does it when you press the gas pedal at higher rpm's. i changed the spark plugs back in october. i pulled them all out and they all looked fine. we were close to an autozone so i went straight there. we hooked the code scanner up and pulled 2 codes. #300 saying that a single or multiple cylender has a mis-fire. and code 304 that says the #4 cylender is misfiring. i checked the plugs again and they were fine. so i went to the next thing in line and bought new spark plug wires and put them on. and it still mis-fires.so then we pulled the coil pack off of it and put it on the tester and it checked good. it had even better readings that a new one that they had. i didnt buy the new one because i dont want to buy anything that wont solve my problem unless i have to as a last resort. i i put the old one back on. i had the battery disconnected thinking that it might clear the code and hopefully not come back. i bought a can of fuel injector cleaner and filled the tank with gas. drove it home and it does idle better so i kow that the new wires helped but didnt cure the problem. it still missed at higher rpm's. should i go buy the new coil pack and see if that does anything????? or takew it ti a shop and have them diagnos it. i will do the work my self i just dont know or have the tools to trouble shoot it. sorry fot the long post. i just really need the car back on the road.
'75 F-100 4x4, 4" lift
35x15.5x15 super swamper TSL/SX
mini-spooled 9" rear end
390 w/ cam,headers,
and 4 barrell edelbrock

TRIED TRUE and FORD BLUE

 

Hello. I can't help ya with that specific problem. Haven't had any CEL's on our 98 Contour yet. Knock on wood. But there is a site specifically dedicated to the Contour/Mystiques.

Here is the link. If it's deleted then shoot me an email and I'll send you the link.

www.contour.org

You should be able to find a quick and helpful answer for your specific problems.

Good Luck! -Ron

 

thanks for the quick post. i just found that site about 2 minutes befor you answered here. i am in the process of registering on it right now so i can post this there.
'75 F-100 4x4, 4" lift
35x15.5x15 super swamper TSL/SX
mini-spooled 9" rear end
390 w/ cam,headers,
and 4 barrell edelbrock

TRIED TRUE and FORD BLUE

 

How many miles on it? Could be the beginnings of a cracked valve, or weak springs.

Jared

 

dont tell me that thats not what i want to hear. jk it has about 115000 on it, not bad for no problems till now.
'75 F-100 4x4, 4" lift
35x15.5x15 super swamper TSL/SX
mini-spooled 9" rear end
390 w/ cam,headers,
and 4 barrell edelbrock

TRIED TRUE and FORD BLUE

 

Just because the plugs arent very old and look ok doesnt mean that they are firing ok under load. it might be the cheapest and easiest thing to try...especially #4 if you had a code for it.

 

well i was gonna change them again anyways just to see if it helps. i have seen plugs go bad at weird times. who knows this might be one of them times. one of the guys on the contour.org web site also said something about a cam positioning sensor being clogged or dirty????? i might see if i can clean that off too.
'75 F-100 4x4, 4" lift
35x15.5x15 super swamper TSL/SX
mini-spooled 9" rear end
390 w/ cam,headers,
and 4 barrell edelbrock

TRIED TRUE and FORD BLUE

 

Usually Cam Position Sensor problems will turn on the check engine light and just make it gutless but wont make it miss.

 

I would replace only plug #4 for now and make sure the wires are routed correctly. Then put noid lights on the harness to make sure the harness is actually firing the plug.

Then I would replace the ign coil pack. Sometimes, unless it has been bad for a while, it is very hard to see hairline cracks by naked eye that are arcing from one terminal to the other.

I would make sure all the recalls have been done on the vehicle. I think on the 99s they replaced the front engine harness as well as one under the dash.

 

[updated:LAST EDITED ON 31-Dec-02 AT 09:33 PM (EST)]If the coil packs are all the same,switch a couple and see if it throws a code for the cylinder that you put the suspect coil on.That should at least tell you whether it is that particular coil pack throwing a code.

If you still have a misfire on that particular cylinder,check the 12 volt wires feeding the coil and their connections before buying parts.

 

well after driving it around a little today it seems back to normal. i got a new plug for the #4 cylinder today but i havent put it in yet. i guess it just needed to drive a little with the new wires in it. hopefully it will stay good and not act up on me again,
'75 F-100 4x4, 4" lift
35x15.5x15 super swamper TSL/SX
mini-spooled 9" rear end
390 w/ cam,headers,
and 4 barrell edelbrock

TRIED TRUE and FORD BLUE