Hot start problem
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I have changed the Speed/ reference sensors, DME and AFM, Battery, alternater, DME relay, FPR and Damper. I have had some trouble gettting her to start, then get her running for a while (30 mins), and now I am having trouble getting her to start after she has been running for some time. Yesterday I let her run for a while, then she shut off out of nowhere. Didnt start right away, but about 2 hours later she started right up, and I shut her off. Today, I was playing with the 2 relays (fan and DME- both the same) and the Clarks DME "Y" jumper. I elimianted 1 of them- the one that wouldnt start the car when she was cold. I got the new DME relay, but she didnt start while she was still warm, above the 1/4 mark. 2 hours later, I started her and she ran for about 10-15 mins., shut her off, and she didnt re-start. Waited for another 2-3 hours, and she started right up. When the tach bounces, she will start right away, 90% of the time, other 10% takes 20 seconds about- happened twice. Other times when she doesnt start, I notic that the tach doesnt bounce.
Just went out side to see if it started, took about 1 second from a cold start for it to run.
Just went out side to see if it started, took about 1 second from a cold start for it to run.
#2
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The first thing you need to do is find out if you're getting spark when it goes into it's no start condition. That will at least narrow the problem down to spark or fuel. Then you can diagnose from there.
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Could be the plugs for the speed/reference sensors. My similar problem was cured by changing the sensor, but my friend had the exact same problem as yours. Whenever it would happen, we'd wiggle the connectors and the car would start.
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No spark when engine is hot/ warm (neddle is in middle of first box) Ignition coil or switch? But will this happen when the engine is hot? Will start when I let her cool all the way. Will start everytime in the morning, or after I havent started for a while 5-6 hrs. Wont try starting her after a long time because I know she probally wont start.
Tried to wiggle the reference sensor when brother was trying to start the car.
When I replaced the FPR and Damper, I was getting fuel due to having fuel from the end nut at the rail, not much (with engine cooled, damper doing it job, correct?)
Tried to wiggle the reference sensor when brother was trying to start the car.
When I replaced the FPR and Damper, I was getting fuel due to having fuel from the end nut at the rail, not much (with engine cooled, damper doing it job, correct?)
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Ok, so you have no spark when it's hot. Good. This problem should be a lot easier to find now. You can forget about the fuel stuff. The lack of spark is your problem. It can only be a few things now. Since you tried wiggling the reference sensors and that did not change anything, we can most likely rule that out. A possibility is that your coil winding is opening or shorting when it gets warm. You could test this if you had the appropriate tools to see if you're getting the trigger signal at the coil from the DME. If you were, then the coil is bad. If you had a spare coil, you could also swap that in for an easy test to see if the problem disappears.
But I suspect you are not getting the trigger. It is a known problem that the DME drive transistors for the coil and fuel injectors develop cracks in the solder joints from heat cycling over 20 some years. The cure is to resolder the joints to the transistors. The easiest way to know if this is the problem is to borrow a known good DME from someone and see if the problem goes away.
If you can't borrow a DME, then if you are knowledgeable about electronics or know someone who is, they can attempt to resolder the transistors, and see if that solves the problem.
Other obscure sources of this problem could be from the wiring harness shorting or opening connections due to expansion of metals when they get warm. Pray this isn't the case or it will take a lot longer to solve the problem.
Good luck!
But I suspect you are not getting the trigger. It is a known problem that the DME drive transistors for the coil and fuel injectors develop cracks in the solder joints from heat cycling over 20 some years. The cure is to resolder the joints to the transistors. The easiest way to know if this is the problem is to borrow a known good DME from someone and see if the problem goes away.
If you can't borrow a DME, then if you are knowledgeable about electronics or know someone who is, they can attempt to resolder the transistors, and see if that solves the problem.
Other obscure sources of this problem could be from the wiring harness shorting or opening connections due to expansion of metals when they get warm. Pray this isn't the case or it will take a lot longer to solve the problem.
Good luck!
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I was trying to start it when it was hot and wasnt getting any tach bounce. I was going to try to adjust the speed/ reference sensor clearence also because when I was trying to get them out I was doing anything and evrything that I could think of to try and get them out. This included prying a flathead under the speed sensor (closer to firewall) placing a hammer on it, and hammering the hammer to try and pry it up. I am guessing that maybee I move the bracket just a little. The spak conditon- I took the ingntiuon coil out, and tried to put an eaxtra spark plug in it (didnt fit snug, very loose) and had my brother try to start the car. I placed the plug near the manifold, and didnt get spark. This was after I tried taking the spark wires out 1 at a time, placing the extra plug in and placing it near the maniflod when brother tried to start the car. No spark on either occasion when engine was hot. An orangee/bluish/yellowish spark (if i remember right) when I did the same procedure by my self when I first started the car (cold)
I replaced the DME and AFM from an '87 and they were both know to be good. Could something have sorthed/ screwed up this DME and my original one that quickly?
I replaced the DME and AFM from an '87 and they were both know to be good. Could something have sorthed/ screwed up this DME and my original one that quickly?
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I also have this going on PleicanCleaned the wires to te starter, didnty "click" when I first start the car, but did when it was hot and did not start. I also cleaned 5 ground wires (batter tray- both ends, behind the engine- just the firewall,couldnt get down to the engine bolt, the ones behind the headlights (2), and the one in the hatch. Couldnt find any more. When I checked the battery while running it was at 13.6DCVs, and then I checked the coil (black meter on (-) battery post and the black wire on the coil and I got 11.0DCVs. I keep checking a few times, and toward the end the coil voltage was at about 9.9 DCVs. When I got it to a no start, battery was at 12.3 DCVs, and the coil was at 9DCVs. I have no idea where to start if it is the wires going to and from. Think I may just goand get a used coil, and see what happens?
EDIT- Tried to start it again, left key in "ON" as always. The battery was at 12.2 DCVs, and I tested the coil, the coil was all over the place. I tested it a few times, and it went from 9.2- 10.2 9.2, 9.3, and lat 3 times was at 9.7 all when battery voltage was 12.2DCVs
EDIT- Tried to start it again, left key in "ON" as always. The battery was at 12.2 DCVs, and I tested the coil, the coil was all over the place. I tested it a few times, and it went from 9.2- 10.2 9.2, 9.3, and lat 3 times was at 9.7 all when battery voltage was 12.2DCVs
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#8
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Try testing the resistance on the coil when hot and cold. You want to do to tests each time:
- Across the two small side terminals (you should see about .75 ohms if I recall)
- Between on of the side terminals and the center terminal (you should see about 11,000 ohms if I remember)
The exact values don't matter too much, as your car works when cold. Test and document the numbers cold, then get it hot enough to make it not start. Test again. If your resistance numbers are way off, you can safely suspect the coil is part of your problem.
- Across the two small side terminals (you should see about .75 ohms if I recall)
- Between on of the side terminals and the center terminal (you should see about 11,000 ohms if I remember)
The exact values don't matter too much, as your car works when cold. Test and document the numbers cold, then get it hot enough to make it not start. Test again. If your resistance numbers are way off, you can safely suspect the coil is part of your problem.
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Well, it was getting dark, but I do have some some #'s for now. Did not know what Large post you meant, Daryl. I took the wire to D-cap out and got nothing, took the rubber plug out and got nothing, there was a whole bunch of black grit that I scraped out of the hole though. With key out of ignition I got .7 ohms between (+) & (-) posts, OL in the wire hole, and rubber hole. While the car was running I got 375 between (+) (-) posts on coil and Ol between each small post and the holes- tried twice. Had a small flashlight in ym mouth and was getting difficult without the sun out. Afetr reading the clarks write up, I was doing test on the (+) post Black wire on the coil. maybee thats why I was getting "OL"
I will edit this tommorow.
Clarks
Ignition Coil Resistance Check
In addition to the test above, you may elect to perform an ignition coil resistance check as confirmation of the coil's condition.
Check the ignition coil primary coil resistance by connecting an ohmmeter between the positive (Black wire) and negative (Green wire) terminals on the coil. The resistance should be 0.4 to 0.6 ohms.
Check the ignition coil secondary coil resistance by connecting an ohmmeter between the coil output terminal and the ignition coil negative terminal. The resistance should be 5000 to 7200 ohms
I will edit this tommorow.
Clarks
Ignition Coil Resistance Check
In addition to the test above, you may elect to perform an ignition coil resistance check as confirmation of the coil's condition.
Check the ignition coil primary coil resistance by connecting an ohmmeter between the positive (Black wire) and negative (Green wire) terminals on the coil. The resistance should be 0.4 to 0.6 ohms.
Check the ignition coil secondary coil resistance by connecting an ohmmeter between the coil output terminal and the ignition coil negative terminal. The resistance should be 5000 to 7200 ohms
Last edited by thekidd; 05-30-2009 at 10:21 PM.
#10
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I hadn't seen that Clark's write up before, but it seems OK. Not terribly descriptive.
That part (checking resistance) should be done with the car off. The two numbers you need both cold and hot are the primary (between the small terminals) and the secondary (between the center post that goes to the distributor and the small post with the green wire).
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OK, did the tests, but cant get a reading from the large post to green wire?
2 small posts cold- .7
large and green wire cold- "OL"
2 small posts HOT no start- .7, but meter was fluctation from .6 up to 8.2 toped out, a few reading between
large post to freen wire HOY no start- "OL"
2 small posts cold- .7
large and green wire cold- "OL"
2 small posts HOT no start- .7, but meter was fluctation from .6 up to 8.2 toped out, a few reading between
large post to freen wire HOY no start- "OL"
#12
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OK, so no significant change on the primaries (the two small posts). You still could have a problem with the secondaries. Just to make sure, as I haven't done this in a while, I did the test myself. Here's what you should be seeing:
On the primaries:
![](http://introspect.net/YouGotSkitched/Aperture-20090531-211901.jpg)
I'm seeing 1.3 ohms. That's from the small terminal on the front side (green wire) to the small terminal on the back side (black wire). A bit much according to Clark's, but well within range of other working coils I've tested. The contacts are also filthy, and I'm not really trying to get an accurate reading (if I were, I'd clean them first).
On the secondaries:
![](http://introspect.net/YouGotSkitched/Aperture-20090531-211950.jpg)
5960 ohms. Or there about. That's from the green terminal in the front to the center conductor that the coil to distributor wire normally goes on. You need to get the probe way down in there to get to the actual conductor part. Yeah, it says 5.96 and it's hard to see, but this meter auto-ranges....you can see a "K Ohms" marking to the right of the display.
In any case, I'm not sure why you aren't able to get a reading from your secondaries, and hopefully it was just how you were testing and this helps.
On the primaries:
![](http://introspect.net/YouGotSkitched/Aperture-20090531-211901.jpg)
I'm seeing 1.3 ohms. That's from the small terminal on the front side (green wire) to the small terminal on the back side (black wire). A bit much according to Clark's, but well within range of other working coils I've tested. The contacts are also filthy, and I'm not really trying to get an accurate reading (if I were, I'd clean them first).
On the secondaries:
![](http://introspect.net/YouGotSkitched/Aperture-20090531-211950.jpg)
5960 ohms. Or there about. That's from the green terminal in the front to the center conductor that the coil to distributor wire normally goes on. You need to get the probe way down in there to get to the actual conductor part. Yeah, it says 5.96 and it's hard to see, but this meter auto-ranges....you can see a "K Ohms" marking to the right of the display.
In any case, I'm not sure why you aren't able to get a reading from your secondaries, and hopefully it was just how you were testing and this helps.
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Thanks for the pictures and the detailing, Daryl. I will test this in a minuets. People over on Pelican Parts are saying that it might be the injecters/ wiring to injecters. Or possibly wiring with the ref./speed sensors. Here is the thread.
http://forums.pelicanparts.com/showthread.php?t=476554
It said pretty much the same here, but a few different things. They had me testing the injecters today- The reference sensor bounces almost everytime I try and crank the car, but it will sonetimes only do it when I first try to start. May do it twice or more other times, but it will almost always bouncve when I try and start it, like if I try (bounce, bounce, bounce), put key in Pos. 1, and try to start it again (bounce maybee once), and try this again, and it might bounce twice.
I did a volt test and resistance test on the injecters/ plugs.when the car was cold (didnt try to start), key in "ON" position, running, and when it was in its HOT/ no start stage (key in pos. 2). Try to stay with me on this.
Cylinder #1
Off- .9 /or 1.0 ohms injector 2.6 ohms
"ON"- 6.8 ohms
Running- 42 ohms. wasnt peged on a number, but it was around
HOT-7.2
"Y" jumper .1 volts 42 ohms
"y" HOT- 0 volts
Cylinder #2
Off- 1.0 /or .9 ohms injector 2.6 ohms
"ON"- 6.7 ohms
Running- 20-42 ohms wasnt peged on a number, but it was around
HOT-7.2
"Y" jumper .1 volts 42 ohms
"y" HOT- 0 volts
Cylinder #3
Off- 1.4 /or .9 / OR 1.0 ohms injector 2.6 ohms
"ON"- 6.8 ohms
Running- 36-42 ohms wasnt peged on a number, but it was around
HOT-7.2
"Y" jumper .1 volts 42 ohms
"y" HOT- 0 volts
Cylinder #4
Off- 1.0 /or .9 ohms injector 2.6 ohms
"ON"- 6.7 ohms
Running- 42 ohms wasnt peged on a number, but it was around
HOT-7.5
"Y" jumper .1 volts 42 ohms
"y" HOT- 0 volts
While running, I got .1DCVs when engine was running with the "Y" jumper and DME relay in. When it was HOT with "y" and DME relay in, it was getting 0 DCVs
Thanks guys for taking your time and trying to help me out. Im sure this is pissing and annoying me more than you guys
http://forums.pelicanparts.com/showthread.php?t=476554
It said pretty much the same here, but a few different things. They had me testing the injecters today- The reference sensor bounces almost everytime I try and crank the car, but it will sonetimes only do it when I first try to start. May do it twice or more other times, but it will almost always bouncve when I try and start it, like if I try (bounce, bounce, bounce), put key in Pos. 1, and try to start it again (bounce maybee once), and try this again, and it might bounce twice.
I did a volt test and resistance test on the injecters/ plugs.when the car was cold (didnt try to start), key in "ON" position, running, and when it was in its HOT/ no start stage (key in pos. 2). Try to stay with me on this.
Cylinder #1
Off- .9 /or 1.0 ohms injector 2.6 ohms
"ON"- 6.8 ohms
Running- 42 ohms. wasnt peged on a number, but it was around
HOT-7.2
"Y" jumper .1 volts 42 ohms
"y" HOT- 0 volts
Cylinder #2
Off- 1.0 /or .9 ohms injector 2.6 ohms
"ON"- 6.7 ohms
Running- 20-42 ohms wasnt peged on a number, but it was around
HOT-7.2
"Y" jumper .1 volts 42 ohms
"y" HOT- 0 volts
Cylinder #3
Off- 1.4 /or .9 / OR 1.0 ohms injector 2.6 ohms
"ON"- 6.8 ohms
Running- 36-42 ohms wasnt peged on a number, but it was around
HOT-7.2
"Y" jumper .1 volts 42 ohms
"y" HOT- 0 volts
Cylinder #4
Off- 1.0 /or .9 ohms injector 2.6 ohms
"ON"- 6.7 ohms
Running- 42 ohms wasnt peged on a number, but it was around
HOT-7.5
"Y" jumper .1 volts 42 ohms
"y" HOT- 0 volts
While running, I got .1DCVs when engine was running with the "Y" jumper and DME relay in. When it was HOT with "y" and DME relay in, it was getting 0 DCVs
Thanks guys for taking your time and trying to help me out. Im sure this is pissing and annoying me more than you guys
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I tested the coil again and got pretty much the same results. I fell stupid, but were those reading with the key in the "ON"position, or did you just pop the hood and take the readings?
Primaries- .7 key "ON" 5.2, 5.6 after I ran the car for a few minuets.
Secondaries- "OL"
Primaries while running- they were all over the place
Secondaries while running- "OL"
I did get .8 DCVs while the car was running.
I beleive that is i the original ignition switch, but I inspected it, and tested it, I got .2 ohms
Primaries- .7 key "ON" 5.2, 5.6 after I ran the car for a few minuets.
Secondaries- "OL"
Primaries while running- they were all over the place
Secondaries while running- "OL"
I did get .8 DCVs while the car was running.
I beleive that is i the original ignition switch, but I inspected it, and tested it, I got .2 ohms