Checking Injector Resistance

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Aug 5, 2013 | 03:34 AM

jmrec100

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Joined: Jun 2013

Posts: 380

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From: Southern California ( for now)

Year: 1994

Model: Cherokee

Engine: 4.0L, In Line 6

Checking Injector Resistance

1994 Jeep Cherokee Sport, 2WD, 4.0L
On line repair manual says the resistance between the injector terminals should read between 3 to 6 ohms. Is that correct? I am replacing my exhaust manifold and since it's apart, been checking things as I reassemble it. I measure the resistance between the Injector terminals at 14.5 to 14.6 ohms for each of the 6 injectors. So are mine still okay? Haven't had any issues with running. Just smog.

Last edited by jmrec100; Aug 5, 2013 at 04:02 AM.

Aug 5, 2013 | 03:52 AM

5-90

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Joined: May 2008

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Year: 1988

Model: Cherokee

Engine: AMC242

Quote:

Originally Posted by jmrec100

1994 Jeep Cherokee Sport, 2WD, 4.0L
On line repair manual says the resistance between the injector terminals should read between 3 to 6 ohms. Is that correct? I am replacing my exhaust manual and since it's apart, been checking things as I reassemble it. I measure the resistance between the Injector terminals at 14.5 to 14.6 ohms for each of the 6 injectors. So are mine still okay? Haven't had any issues with running. Just smog.

Dunno where they got 3-6 ohms, that's not right. Nominal resistance is 16ohms, with an "acceptable" range of 14-18ohms. Nominal injector firing current is about 1A - too much, and you'll overload the injector drivers (there are injector styles that take much more current to fire - but they are usually aftermarket, not OEM.

Aug 5, 2013 | 04:01 AM

jmrec100

Thread Starter

Seasoned Member

Joined: Jun 2013

Posts: 380

Likes: 1

From: Southern California ( for now)

Year: 1994

Model: Cherokee

Engine: 4.0L, In Line 6

Thanks. I thought so too. Would be too weird for ALL to be bad at one time. Appreciate it.
Autozone online manual says 5 ohms. Where do they get these figures?
Thanks. I feel okay about putting them back in.

Last edited by jmrec100; Aug 5, 2013 at 04:05 AM.