Current Classifieds

99' 2.5l lima cylinder head

Date: 01/13/2017 01:56 am
Need hatchback fuel tank sending unit
Date: 08/13/2018 02:46 pm
Wanted: Oil Breather F0ZZ6A485A "87-8 from 2.3L Turbo
Date: 08/06/2021 02:23 pm
1972 Pinto SCCA BS race car

Date: 10/23/2018 04:01 pm
need a Ford battery for a 77 Pinto
Date: 02/21/2017 06:29 am
I'm looking for a 78 or older Pinto near Alberta
Date: 08/13/2021 10:39 am
Odds and Ends 1976-77 Pinto Wagon

Date: 07/17/2019 05:23 pm
Early V8 swap headers, damaged, fixable?
Date: 10/25/2019 03:30 pm
Pinto Engines and engine parts
Date: 01/24/2017 12:36 pm
1974 points distributor for 2.3l
Date: 07/04/2022 07:55 pm
13x6 minilite style wheels MAKE OFFER——NEED GONE

Date: 08/01/2018 01:17 pm
74 & Up Parts
Date: 01/20/2021 03:22 pm

Author Topic: resistance testing  (Read 1334 times)

0 Members and 1 Guest are viewing this topic.

Offline hqtoyou

  • Pinto Driver
  • *
  • Posts: 7
  • FeedBack: +0/-0
  • Another Pinto Driver

  • Total Badges: 1
    Badges: (View All)
    Topic Starter
resistance testing
« on: September 15, 2012, 03:19:23 PM »
My Multimeter when set on the lowest setting shows approx. 3.0 when I hold the test probes with my hands so I know that it will read low resistance but when I do any resistance checking on my coil posts while out of the car it reads 0.00 and any other values that I try to check on the car as shown in the repair manual everthing read 0.00. Does this mean that my coil is damaged and I have a grounded wire somewhere in the car that may have damaged the coil? My multimeter when set and ready for testing reads 1_.__ then counts down quickly to 0.00 when checking for resistance on the car.

Offline ToniJ1960

  • Pinto Sr. Member
  • ****
  • Posts: 544
  • FeedBack: +13/-0
  • Gender: Female
  • Another Pinto Driver

  • Total Badges: 5
    Badges: (View All)
    Tenth year Anniversary Topic Starter Poll Voter Fifth year Anniversary Windows User
Re: resistance testing
« Reply #1 on: September 15, 2012, 04:21:10 PM »
 ok a few things when youre measuring resistance.

 1. the range if its 1k full scale .oo1 is a tenth of one ohm. A few feet of wire is about that much resistance. If you have some solenoids or resistors (even better) check to see if the resistance shows up correctly on the meter. A 12 vdc solenoid could be around 50-100 or 200 ohms maybe up to 1000 ohms. If youre reading the resistance of your skin holding the probes in your fingers  and the meter shows uner full scale like 300, then youre not on 1k full scale more likely its on 100k full scale or something like that, maybe even 1m full scale then .001 1000 ohms and you wont be  able to measure smaller resistances on that range. Skin resistance is much higher than 300 ohms.

2. if the battery is weak it can give all kinds of weird readings on resistance measurements

3. if theres any residual voltage where youre measuring, it can alter the reading and potentially ( pun sort of intended) damage your meter. Resistance range is the most susceptible to damage this way

 So check your range carefully, check your battery, and use the voltmeter first to make sure theres no (not even tiny) amount of voltage across the points youre going to check for resistance/continuity.

Offline ToniJ1960

  • Pinto Sr. Member
  • ****
  • Posts: 544
  • FeedBack: +13/-0
  • Gender: Female
  • Another Pinto Driver

  • Total Badges: 5
    Badges: (View All)
    Tenth year Anniversary Topic Starter Poll Voter Fifth year Anniversary Windows User
Re: resistance testing
« Reply #2 on: September 15, 2012, 04:28:44 PM »
 one more thing if a dmm has been damaged by voltage placed on it in the ohms mode sometimes the meter can be damaged in a way that makes any resistance show as .000 so its a good idea to check it against a known resistance.

Offline hqtoyou

  • Pinto Driver
  • *
  • Posts: 7
  • FeedBack: +0/-0
  • Another Pinto Driver

  • Total Badges: 1
    Badges: (View All)
    Topic Starter
Re: resistance testing
« Reply #3 on: September 15, 2012, 07:55:36 PM »
Thank you for the reply. I'll check it out. By the way this all started when I had a rough idle and found out that none of the cylinders are firing  consistently. I've check every possible reason for this and any repairs that I have done to the ignition system has changed nothing at all.New ICM,plugs,plug wires,coil,cap and rotor,pickup coil,distibutor,any elec. plugs that looked bad. There is just no change at all. Also, could you possibly tell me where the resistance wire is on a 1978 pinto?