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Discussion Starter #1
My 86 Turbo Z has been having some ignition/fuel problems since i got it running (bought it a month ago). When im at idle in gear and the engines warm, after a few seconds the idle starts to bounce down to about 500 from a thousand, and will eventually die if i dont control the idle with the gas pedal. So i thought it was the ignition coil and i switched it from another daytona that had a newer coil. I now get no spark whatsoever. I know the wires are on correctly because they only go one way on the old coil and pos/neg is marked on both. I put the old coil back in and still nothing. I dont know where any fusible links or anything are, but none of the regular fuses are blown. If i jump the coil with the positive battery terminal i get some spark but after one try (i was late) it wouldnt fire. Any ideas? :bang head
 

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Discussion Starter #2
I went back to work on it some more after dinner, and got some more information. I read in some other posts that it could be the HEP (whatever the hell that is), which i determined to be in the distributor (?). So i switched distributors from a parts car i have (89 T1 auto, mines an 86 T1 auto), but no good. When i jump the coil from the battery with the coil wire attached, the fuel pump goes off and doesnt stop. When i then crank the engine it fires and sounds better than it did before. However, removing the jumper kills the engine. Also, jumping the green and black wire (coil positive) from the computer deal (bottom right of the engine bay) to the coil does nothing, which scares me. Does anyone know what the problem might be, and if its the computer is it possible to switch an 89 T1 auto comp to my 86 T1 auto?
 

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Discussion Starter #4
So i appreciate all the help im getting guys, really i do. ::jerks:: just kidding. Stupid car is aggrivating me. Anyway, i was wondering if you need a special reader to get the diagnostic codes? It seems like most people know what codes theyre getting and i didnt think it likely that all those people had a specialty tool, so just wondering. And if so, where can i get one and at what cost? Thanks to anyone who actually knows how to help me or is willing to.
 

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the HEP is the black disc under the dist cap. It should have 2 wires coming out of it.

to get the codes sit in car and turn key on-off 3 times quickly. the check engine light will start flashing count the flashes ie code 11 would be flash long pause flash long pause 11 is the code for bad hep. visit http://minimopar.knizefamily.net/fault/index.html for a complete discription

i am not sure where the fusable links are on an 86. In my 88(smec setup not the lm setup you have) they are very close to the battery. visit www.thedodgegarage.com and read the info there very good.
 

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Discussion Starter #6
Thanks. I tried to get codes but nothing happens. Whether i crank the engine then try it or not, the power limited light doesnt flash. I tried turning the key a bunch of times (like seven) to see if that did anything, but nothing happened. The light comes on, but doesnt flash. If i leave the key on for a few seconds it goes off and stays off. Is this a sign of a bigger problem?
 

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Discussion Starter #8
brand new, no chance thats the problem. It runs my 250W sub amplifier with no problem also, even without the engine running. I might be causing electrical gremlins with the amp, but i turned it off for about an hour of driving (I wired a switch to the coil with power, as described above, runs fine like that except that the fuel pump is always on), and nothings changed
 

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I have a not needed 86 Laser T1 auto logic module, and any 85-87 turbo power module will work. Check the 10 way and 12 way plugs on the power module (black box between battery and fender) I had a mysterious no start on mine and it was apparently one of the plugs. The ASD relay is part of the power module on the 2 piece system, what you have done is bypass it with your switch. You should at least get an 88 code from yours if you follow the procedure on-off-on-off-on and wait for the codes. You don't start it, just turn the key on and off. Let us know, may be some one near you on this group can help you.
 

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Discussion Starter #10
Thanks everyone. What exactly goes wrong with the plugs on the logic module? I took them off and wire brushed them with no change. Would I be able to open the lm and see if one of the components went bad?

What is the HEP supposed to look like and how would it go bad?

How much would you charge for that logic module, if you're willing to sell it?
 

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LM, $25 + shipping. HEP is black plastic disk with 2 slotted sensors on the bottom side. Has 2 3 wire leads with round plugs, plugs are gray and black. This is triggered by a shutter wheel in the bottom of the distributor. As to failure mode, why I don't know, but they just stop working. Turbos need 2 pickups, one for the normal ignition and the other to "snyc" the injectors. I don't really have a use for the LM, it is too hard to convert to T2, and I have an extra 87 LM anyway.
 

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it doenst sound like you pulled codes correctly. you have to turn the key from off to run three times and then leave the key in the run position. should pause for a second and then start flashing. if there are no codes you will see it flash 5 times, pause, 5 more times, and then there will be a long pause and it will repeat.

try to be more descriptive with your diagnostic method. it seems like you're just throwing parts at it. that can be costly and time consuming.
 

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Check your grounds... especially the one that supposed to go to the firewall. That braided POS always rots away, causing interesting things to happen.
 

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Discussion Starter #14
Not so much throwing parts, but just trying to rule out certain parts... the problem is im easily distracted. I know its nothing after the ignition coil (besides possibly HEP), and theres no problem with the fuel system at least related to this, because the car runs when i give power to the coil (and therefore the fuel pump for reasons i do not understand). If the car will run without the HEP then that could be it if what i did bypassed it, but my thought is the ASD relay as 85lebaront2 said, which if i remember correctly from thedodgegarage.com, will cause this problem. I know my methods are downright horrible, but im completely clueless with this, something that has never happened before. The wire going from the lm to the coil is intact, there is no voltage coming from the lm on the coil wire (green/black stripe). This seems to be the only reason why its happening, but i dont know what that means. If anyone knows anything about an 86 lm, or anything related to this, please, im preparing the pipe bombs for this cars final trip as we speak, and only your information can save this car from a firey death. :bash:
 

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Hey NighTHawk, it sounds like your problem is in the PM, not the LM. The PM is the black box next to the battery. I have a spare, but wanted to keep it for mine, at least until I see if I am going to go to a SMEC for mine. Any 85-87 turbo PM will work, the A1 Cardone rebuilt number is 79-7966. See if you can borrow one to try. The ASD is part of it.
 

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Discussion Starter #16 (Edited)
That black box is what ive been looking at this whole time, i thought that was the logic module (lm). Still learning apparently. What does PM stand for? can i transfer it from an 89 T1 auto without too many mods? Is there any other way to diagnose a problem with the ASD to make sure thats what it is?

Let me be clearer on how i tried to get codes:
Turned the car on-off-on-off-on. Didnt unlock the key, didnt crank the engine. The 'Power Limited' light goes on, after a few seconds it turns off, doesnt flash. I waited about twenty seconds after it went off and it still didnt flash. I just unplugged my neg bat cable to try and reset the computer system(s) and see if it makes any difference.
 

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CANNOT TRANSFER FROM ANY CAR 88 AND UP. THEY ARE COMBINED (P)OWER (M)ODULE/LOGIC MODULE.

Your car has separate modules. The PM is under the hood, the LM is under the front passenger kick panel.
 

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Where NW of Chicago are you? I may have a spare power module around that you can try.

The problem does sound like something in you ASD circuit, the ASD relay is inside the power module on your car. The computer uses the ASD to power up the coil and the fuel pump so the descriptions you gave are what it's supposed to do if you put power to the + side of the coil.
 

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Hmmm...not sure why you can't get codes out of it. To see if you are really in diagnostic mode, press the brake pedal after the power loss light goes out. It should come on when you press it (switch test). If it doesn't, try cycling the key again. The fact that the motor runs says the LM is at least somewhat sane. Another sign that you are in diagnostic mode is that the tach jumps from zero up to 1500 rpm or so.

Do you have a volt meter? If so, connect it across the coil, reset the computer by disconnecting the battery and then turn the ignition key to "on". You should see 12V for about one second across the coil. You should also hear the fuel pump run for a bit.
 
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