Diagnose no start, Update: Need Relay board -> 74 2.0L |
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Diagnose no start, Update: Need Relay board -> 74 2.0L |
boxsterfan |
Jul 4 2014, 01:47 PM
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#1
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914's are kewl Group: Members Posts: 1,776 Joined: 6-June 03 From: San Ramon, CA Member No.: 791 Region Association: Northern California |
On my way home on the freeway last night, my 74 2.0L just died travelling along at 70 MPH. Had her towed home.
Looking at it today, it appears there is no spark. If I turn the key, I can hear the fuel pump so seems like I got power there. I have a newer Bosch coil from PP that I put in a few months ago (it's one of those silver looking ones but a Bosch unit). I replaced the coil back with the old one and still no start. Car cranks, but no fire. The car has Pertronix in it. I suspect this is what died. Does that sound right to the folks here? |
JeffBowlsby |
Jul 4 2014, 02:12 PM
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#2
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914 Wiring Harnesses Group: Members Posts: 8,663 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None |
Those are notorius for dying. Try a set of points.
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Mblizzard |
Jul 4 2014, 02:15 PM
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#3
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Advanced Member Group: Members Posts: 3,033 Joined: 28-January 13 From: Knoxville Tn Member No.: 15,438 Region Association: South East States |
Have you verified the lack of spark? Just checking because you said it appears that it has no spark.
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boxsterfan |
Jul 4 2014, 02:23 PM
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#4
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914's are kewl Group: Members Posts: 1,776 Joined: 6-June 03 From: San Ramon, CA Member No.: 791 Region Association: Northern California |
Have you verified the lack of spark? Just checking because you said it appears that it has no spark. I haven't verified. I assume I'll need a help to crank the ignition while I hold one of the plug wires (plug end) next to some metal (the body). Rookie weekend mechanic here.... |
Mblizzard |
Jul 4 2014, 02:45 PM
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#5
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Advanced Member Group: Members Posts: 3,033 Joined: 28-January 13 From: Knoxville Tn Member No.: 15,438 Region Association: South East States |
If you work alone a lot set yourself up a remote start switch. Essentially across the starter. Or you can make two long leads with clips. Place spark plug in a wood board (hole drilled in board works nice) attach one lead on the spark plug wire then to the top of the plug. Take the other lead and find a good ground then place the clip on the bottom of the plug. Crank and you can see the spark in the drivers seat.
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boxsterfan |
Jul 4 2014, 06:16 PM
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#6
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914's are kewl Group: Members Posts: 1,776 Joined: 6-June 03 From: San Ramon, CA Member No.: 791 Region Association: Northern California |
So I checked for spark by pulling the #1 plug wire, hooking up to spark plug directly, vampire clip in the spark end of the plug and a wire that I ground to the body. I had a helper cranking the motor for me.
I saw spark there, but is sure seemed awful weak. I've never seen the spark on a plug outside the motor. And of course, my ground could have been poor also as i was just rigging this up to see if there was any spark. How "strong" should the spark be or look? Otherwise I got spark (weak?), and I hear the fuel pump running, then what's next? This is a 74 with the "seatbelt relay" under the passenger seat. These things are famous for causing issues. One time, mine caused the car to not start (except the symptom was that it wouldn't even crank). I ended up re-seating all the connections under there (6 months ago) and had been fine until now. Otherwise? I dunno... (IMG:style_emoticons/default/confused24.gif) (IMG:style_emoticons/default/confused24.gif) |
Bartlett 914 |
Jul 4 2014, 06:25 PM
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#7
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Advanced Member Group: Members Posts: 2,216 Joined: 30-August 05 From: South Elgin IL Member No.: 4,707 Region Association: Upper MidWest |
So I checked for spark by pulling the #1 plug wire, hooking up to spark plug directly, vampire clip in the spark end of the plug and a wire that I ground to the body. I had a helper cranking the motor for me. I saw spark there, but is sure seemed awful weak. I've never seen the spark on a plug outside the motor. And of course, my ground could have been poor also as i was just rigging this up to see if there was any spark. How "strong" should the spark be or look? And I got spark, and I hear the fuel pump running, then what's next? This is a 74 with the "seatbelt relay" under the passenger seat. These things are famous for causing issues. One time, mine caused the car to not start (except the symptom was that it wouldn't even crank). I ended up re-seating all the connections under there (6 months ago) and had been fine until now. Otherwise? I dunno... (IMG:style_emoticons/default/confused24.gif) (IMG:style_emoticons/default/confused24.gif) Seatbelt relay will prevent the engine from cranking. Since you can crank, that isn't your problem. |
Java2570 |
Jul 4 2014, 07:17 PM
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#8
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Senior Member Group: Members Posts: 649 Joined: 7-May 11 From: Fishers, IN Member No.: 13,035 Region Association: Upper MidWest |
Check the ground wire that runs between the points plates in distributor....if it comes off, it can cause a no start situation.
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Mblizzard |
Jul 4 2014, 07:57 PM
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#9
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Advanced Member Group: Members Posts: 3,033 Joined: 28-January 13 From: Knoxville Tn Member No.: 15,438 Region Association: South East States |
Ok some good suggestions. But I would check the wires to be sure they are not broken especially the coil wire. Make sure the cap and rotor are in good condition.
For fun, take a heavy gauge wire and attach it to the engine case and the negative side of the battery. Then recheck the spark and try starting. Verify that the magnet on the distributor shaft has not slipped. Make sure the Petronix unit is tight to the distributor plate and the gap between the unit and the magnet is correct. Remove and check all plugs. Before putting the plugs back in get the engine to TDC and verify that it is pointing to number 1 cylinder. If you don't find any problems slips a set of points in it and see what happens. Or you could just skip all of than and start with the points first! Which ever way you go, it will always turn out you should have gone the other. |
boxsterfan |
Jul 4 2014, 08:00 PM
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#10
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914's are kewl Group: Members Posts: 1,776 Joined: 6-June 03 From: San Ramon, CA Member No.: 791 Region Association: Northern California |
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boxsterfan |
Jul 4 2014, 08:03 PM
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#11
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914's are kewl Group: Members Posts: 1,776 Joined: 6-June 03 From: San Ramon, CA Member No.: 791 Region Association: Northern California |
Ok some good suggestions. But I would check the wires to be sure they are not broken especially the coil wire. Make sure the cap and rotor are in good condition. For fun, take a heavy gauge wire and attach it to the engine case and the negative side of the battery. Then recheck the spark and try starting. Verify that the magnet on the distributor shaft has not slipped. Make sure the Petronix unit is tight to the distributor plate and the gap between the unit and the magnet is correct. Remove and check all plugs. Before putting the plugs back in get the engine to TDC and verify that it is pointing to number 1 cylinder. If you don't find any problems slips a set of points in it and see what happens. Or you could just skip all of than and start with the points first! Which ever way you go, it will always turn out you should have gone the other. Spark plug and coil wire are Clewett brand (spiral, 1200 degree) bought from PP less thaa 6 months ago. Those should be good. I don't have a set of spare points. I'll take a look at TDC and the plugs tomorrow. I think I'll get another Pertronix on order (couldn't hurt to have a spare anyway.) |
boxsterfan |
Jul 4 2014, 09:02 PM
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#12
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914's are kewl Group: Members Posts: 1,776 Joined: 6-June 03 From: San Ramon, CA Member No.: 791 Region Association: Northern California |
I went at looked at the ground strap on the contact breaker plate. Looks OK.
Attached thumbnail(s) |
Java2570 |
Jul 4 2014, 09:43 PM
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#13
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Senior Member Group: Members Posts: 649 Joined: 7-May 11 From: Fishers, IN Member No.: 13,035 Region Association: Upper MidWest |
Ground in dizzy appears ok.....pretty dirty in the dizzy though. It could definitely be a fried Pertronix module or perhaps one of the wires from the module to the coil has come loose in it's connector? I've got Pertronix and I've had that happen due to a poor crimp on the connector (my fault). I've not had a module fry out suddenly but I know that it could happen. My goal is to have a spare dizzy in my emergency kit setup and ready in case something happens like that. And I'd look at the rotor and cap as well....
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boxsterfan |
Jul 4 2014, 10:04 PM
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#14
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914's are kewl Group: Members Posts: 1,776 Joined: 6-June 03 From: San Ramon, CA Member No.: 791 Region Association: Northern California |
Ground in dizzy appears ok.....pretty dirty in the dizzy though. It could definitely be a fried Pertronix module or perhaps one of the wires from the module to the coil has come loose in it's connector? I've got Pertronix and I've had that happen due to a poor crimp on the connector (my fault). I've not had a module fry out suddenly but I know that it could happen. My goal is to have a spare dizzy in my emergency kit setup and ready in case something happens like that. And I'd look at the rotor and cap as well.... Since I don't have a set of points and condensor, I guess I'm going to just order another Pertronix and test it out. Worst case I have a spare/backup Pertronix if that doesn't fix it. Cap and rotor are around 6 months old (same as coil). After that, I don't know what it could be? Ignition switch going bad? I |
JeffBowlsby |
Jul 4 2014, 10:28 PM
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#15
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914 Wiring Harnesses Group: Members Posts: 8,663 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None |
I should have an extra set of points if you need to try them.
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boxsterfan |
Jul 5 2014, 12:13 PM
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#16
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914's are kewl Group: Members Posts: 1,776 Joined: 6-June 03 From: San Ramon, CA Member No.: 791 Region Association: Northern California |
So this morning, I checked over everything again:
1. Bullet Fuses in relay board are fine. 2. Bullett Fuses under dash are fine. 3. Connections to coil are fine (no loose wires at crimp). 4. Spark plug wires and coil wire are less than 6 month old Clewett wires from PP. Should be fine. 5. I did a spark test yesterday, and did get some spark. Not sure on if it was "weak" or not but there was spark. So, if motor cranks and I got spark that leave fuel as suspect. Question about fuel pump operations: 1. When you turn the key, should you hear the fuel pump kick in? This is a 74 2.0L with fuel pump moved up front. I thought I heard it yesterday, but I didn't hear anything this morning. 2. How do I go about checking the fuel pump electrically? Later this afternoon, I plan on removing the underbelly pan and having a look at the connections to the pump (loose wire?) and looking to see if the hoses are not crimped. The best part is I just fueled up on gas and have 3/4 tank full which would make replacing the fuel pump that much more fun. |
JeffBowlsby |
Jul 5 2014, 12:26 PM
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#17
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914 Wiring Harnesses Group: Members Posts: 8,663 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None |
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Bartlett 914 |
Jul 5 2014, 12:45 PM
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#18
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Advanced Member Group: Members Posts: 2,216 Joined: 30-August 05 From: South Elgin IL Member No.: 4,707 Region Association: Upper MidWest |
Spray some starter fluid or brake cleaner in the intake and see if it fires. That will help see if it a fuel issue
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Java2570 |
Jul 5 2014, 02:11 PM
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#19
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Senior Member Group: Members Posts: 649 Joined: 7-May 11 From: Fishers, IN Member No.: 13,035 Region Association: Upper MidWest |
The fuel pump should kick on for a second or so when you turn on the ignition key.
Did you test the fuses and the fuse holders for continuity with your meter? They can go intermittently bad. |
boxsterfan |
Jul 5 2014, 07:51 PM
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#20
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914's are kewl Group: Members Posts: 1,776 Joined: 6-June 03 From: San Ramon, CA Member No.: 791 Region Association: Northern California |
So I finally got the 2.0L started again. Fuel pump not getting power is the issue.
I think my relay board is bad. The reason I think this is that my AAR is having trouble also (not closing). I had issues with my AAR last fall and ended up replacing with another used one and at the time it didn't fix it. I ended up finding corrosion under the main power relay on the relay board. Cleaned that up and the AAR started working. So back to today, fuel pump power seems intermittent. AAR power seems intermittent. Took out relay board and cleaned it up on top (had a couple minor little corrosion spots). I believe the two have the relay board in common. I'm feeling like this is the likely cuplrit anyways. And another odd note if it helps: The red "brake light" (normally seen lit when emergency brake is engaged) has been always "on" in my car for about 6 months. Now, it likes to just blink on/off all the time. When it stayed always on, it would also blink in conjunction with a turn signal if that was engaged. Also, the blinking on/off just started and of course this is what started this thread (car died on the highway). Going to put a WTB up for a relay board. Can you get these new? |
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