bad coils?

[snatiep]

Hello Everyone,

My '96 Ranger 2.3L had developed a miss, mostly at idle. I'm suspecting an ignition coil.

I tested between the 3 terminals on the connectors and had .5 ohms.

Between the plug towers, 14.38K ohms to 14.94K ohms.

Here's what the Chilton manual says:

"If the resistance for all of the readings was between 6,500-11,500 ohms, the ignition coils are OK. If any of the readings was less than 6,500 ohms or more than 11,500 ohms, replace the corresponding coil pack."

The book says these readings are too high and out of specs. Could that be causing the missing?

***edit*** it's definitely an idle issue. When I leave it in 1st gear and idle up a small hill it starts bucking and missing. On the road cruising it runs fine.

I replaced the intake coil two years ago with a used salvage yard coil because I got a check engine light referring to that coil, and at the same time I replaced the plugs and wires.

Thanks for any help.

Nate

 

[dmassey]

My Chilton's says the primary resistance (from the middle pin to either of the side pins) should be less than 5 ohms and the secondary resistance ( between towers) should be 13-15 K ohms so according to thos e numbers your coil should be okay however it could be breaking down when hot and I didn't understand if you checked the readings with the engine hot or cold.

 

[jdmzach]

check your brake booster, unplug the vacuum hose going to it and put a big bolt into the hose to plug it, then start the truck, if it idles fine like it should then your booster has a leak thats causing the missing. I had this problem and another member here told me to try that, and sure enough it was my problem, so i just left my booster vacuum hose plugged with a bolt and drive the truck like that, it makes the brake pedal stiff as hell and have very little brakes but id rather drive with very little brakes than have my truck missing and run like shit. Eventually ill get around to pulling the booster and fixing it, but it looks like a PITA so im avoiding it as long as i can.

So plug up the vac hose and take it for a drive, but dont go down any hills and keep your foot on the brake in case you need to stop quick, and be prepared to put alot of weight on the brake when you need to stop b/c the pedal is gonna be hard to push.