HELP. trouble starting 72 1.7L |
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HELP. trouble starting 72 1.7L |
forzamotorsport9 |
Nov 17 2009, 10:30 PM
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#1
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Newbie Group: Members Posts: 44 Joined: 2-November 09 From: Bettendorf Iowa Member No.: 11,001 Region Association: Upper MidWest |
ok so i installed my tangerine racing tunnel and engine compartment lines no problem there, installed a 34R Optima Red-Top, a little big but oh well, went to turn it over, wouldnt turn over. i looked and coming off of the coil is a green wire attached to nothing, i think its a ground. where does this thing go.
any ideas on getting it started and where that ground needs to go. i would figure the engine case but i tried holding it there and pulled out a spark plug and hooked back to the wire to see if it would start and got nothing, i then grounded it to a bolt connecting the tin cover (i think?) to the head and the continuity tester said the circuit was ok so im guessing something has to be wrong with the ignition system, either the coil or distributor, which i THINK is newer and uses the magnetic thing to adjust dwell, which i loosly understand the concept of. also, could it just be the spark plug? it didnt look fouled or anything but i couldnt see a visable spark when having someone try to start the car and it wouldnt gap to the engine case either, so idk whats up im only 18 and a senior in high school so a lot of this is new to me, ive read about it in magazines but never this deep, nor got my hands dirty (i have now! (IMG:style_emoticons/default/beerchug.gif) ) i just wanna see the damn thing run, for only having 47,259 miles on the clock it shouldnt be too big of a deal to fix. i included a picture of what it looked like with just a basic clean too, no detailing or anything, not bad for being 38 (i think?) years old!) i trust the ppl on this site too, so if anybody want my phone number just shoot me a pm and id be more than happy to discuss it on the phone. THANKS IN ADVANCE. note: the green wire in the one pic is the one i grounded. it was just sticking up like in the picture before i grounded it |
Spoke |
Dec 8 2009, 01:36 AM
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#2
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Jerry Group: Members Posts: 7,052 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None |
Here's a couple of simple tests to check for proper voltages:
Test 1: Power Supply Relay operation: 1a) Remove the plug from the ECU. This is 4 pronged ECU connector near the driver rear of the relay board with white wires going towards the ECU. We'll call the 4 pins on this connector: Pin I is passenger front Pin II is passenger rear Pin III is driver front Pin IV is driver rear 1b) turn ignition switch ON. You should hear a low click when the middle relay turns on. (Power Supply Relay; it's the middle one if you have 3 relays or the front one if you have 2 relays) 1c) Measure voltage on ECU connector pin I (passenger front). It should be 12V. **************** If 1c) is not 12V, then we have to find out why the Power Supply Relay is not turning on. Do not do the next test. If 1c) is 12V, then proceed to test fuel pump relay: **************** Test 2: Fuel Pump Relay Energizing: 2a) Keep ECU plug off. Turn ignition switch OFF. 2b) Get a piece of wire 2 feet long or longer with a female spade on it like shown below. Connect this spade to ECU connector pin III (driver front). WARNING: The reason for the spaded wire is that Pin I on this connector is 12V through the power supply relay directly to the battery WITH NO FUSE. Accidentally touching Pin I to ground (we're grounding pin III right next to it) can cause serious damage and sparking. 2c) Once the spade is connected to Pin III, hold the other end of the wire up in the air (not connected to anything). Turn ignition switch ON. 2d) Touch and re-touch the other end of the wire to a clean chassis ground. Listen for the fuel pump relay to click when the wire is touched to a clean chassis ground. **************** If 2d) yields Fuel Pump Relay clicking, proceed to test 3. **************** Test 3: Fuel Pump Voltage 3a) Remove power connector from fuel pump. 3b) Ground ECU connector pin III (driver front) like in 2b through 2d). 3c) Turn ignition switch ON. 3d) Measure 12V across the 2 wires of the fuel pump connector. **************** If 3d) yields 12V, then the circuitry to power the fuel pump is ok. Sorry for the length of this post and the detail. If this stuff was easy my post would be like 10 words long and you'd be driving your car now. It is not easy and a methodical approach will lead us to the fault or faults. Hang in there, we will get you through this. If you can't get through this, PM me and we can talk on the phone while you test. Good luck. Wire for grounding ECU connector Pin III: Attached image(s) |
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