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Topic: '86 Cougar 5.0 V8 - Rough idle after starting (only when motor is warm)... (Read 2317 times) previous topic - next topic

'86 Cougar 5.0 V8 - Rough idle after starting (only when motor is warm)...

Hey everyone!

I'm having a problem that I'm scratching my head trying to figure out.  I had posted a month or so that I had changed my spark plugs as they were the original spark plugs that came on the car.  I have an '86 Cougar 5.0 V8.  I get smooth idle when I first start the car for the day.  If I go somewhere after the motor has warmed up, then come out to start the car again, it idles pretty rough (rumbling and bumbling the way it feels), almost to the point it acts like it wants to cut off.  I haven't changed the spark plug wires, distributor or rotor. 

Anyone got any ideas?  Any help would be greatly appreciated!  :-D

Thanks in advance,
Tommy

 

'86 Cougar 5.0 V8 - Rough idle after starting (only when motor is warm)...

Reply #1
Replace your wires, cap and rotor. Check your coil and take your ign. module to autozone to get tested.
How fast is fast?

'86 Cougar 5.0 V8 - Rough idle after starting (only when motor is warm)...

Reply #2
Where do you find the coil and ignition module?  My other question is, will the car shut off while it's still doing this?  So far it hasn't, but I'm wondering if it might.  Money is tight right now, so I can't change out a lot of parts on it.

'86 Cougar 5.0 V8 - Rough idle after starting (only when motor is warm)...

Reply #3
Do you have any check engine lights, does it smoke?
How fast is fast?

'86 Cougar 5.0 V8 - Rough idle after starting (only when motor is warm)...

Reply #4
No check engine lights and it doesn't smoke at all.

'86 Cougar 5.0 V8 - Rough idle after starting (only when motor is warm)...

Reply #5
Does it eventually smooth out? Or do you have to wait until it cools off?
CoogarXR : 1985 Cougar XR-7

'86 Cougar 5.0 V8 - Rough idle after starting (only when motor is warm)...

Reply #6
As long as the motor is warm, it will continue to do it.  If it's cold, whether starting it for the first time, or after the motor has cooled down, it's smooth.

'86 Cougar 5.0 V8 - Rough idle after starting (only when motor is warm)...

Reply #7
If you start the car cold, and drive it until it gets warm, but don't turn it off, is it still fine? Or will it start acting up as it's heating up?
CoogarXR : 1985 Cougar XR-7

'86 Cougar 5.0 V8 - Rough idle after starting (only when motor is warm)...

Reply #8
From what I can tell, it's still fine if I don't turn it off.  I'll check for sure either later this evening or tomorrow.

'86 Cougar 5.0 V8 - Rough idle after starting (only when motor is warm)...

Reply #9
What about the TFI module?  I think they can act up when hot.
Mike

'86 Cougar 5.0 V8 - Rough idle after starting (only when motor is warm)...

Reply #10
Where's the TFI module?

'86 Cougar 5.0 V8 - Rough idle after starting (only when motor is warm)...

Reply #11
Quote from: thetommyboy2k;447339
Where's the TFI module?

It's mounted on the side of the distributor
1987 T-Bird TC: 5-Spd, 5-lug conv., CHE Rear CAs, '04 Cobra wheels and 13" Brakes, Vac Assist conv: '93 Cobra BB/MC & Wilwood PV, Gutted/Knived Intakes, T3 turbo, RFE6 Mani, Stinger 3" Exhaust & Oil Feed, 255HP Walbro, Kirban AFPR, RR Cam, Esslinger Cam gear and Round Tooth Conv., Gillis Boost Valve, Speedway Dual Valve Spring,  K&N, 130a 3g Alt conv., 140mph Speedo
Running Better Than Ever :burnout:

'86 Cougar 5.0 V8 - Rough idle after starting (only when motor is warm)...

Reply #12
If you replace it, it is generally accepted to use only a Motorcraft piece, not aftermarket/parts store junk.
Mike