MSD DIS 4 ...........burned out? symptoms?

[Tiago]

Ive been having a problem with the ignition on my car so I think. Ive been running a dis4 on my stock coils and ign module, worked great, until about a week ago my car started missing and hesitating like a mofo...I take the coils off and they had burn marks on the prongs...ok. new coils and new ign module go on, car runs hella smooth without the msd, plug msd back in, hesitation comes back.

those that have had a problem with their msd, does this sound like the box is fried?

I know alot of other people have had problems making the unit work, they follow the same wirign schematic that I did, however theirs doesnt' work, mine did on the OEM ign module, now seems to not unless the box IS fried...any ideas???

Mike Huff, you said you fried a couple of these units, how did the car act when it happend?

I posted this in advanced tech because its not really simple, its a more complicated in depth problem solving post.

[black34v6]

I have a similar problem -- one of the things Tiago did was buy a replacement ignition module from an aftermarket source.

I bought the MSD DIS-4 a while back and mine also runs great with it disconnected, the minute I plug the MSD in, the car runs like its missing one or two cylinders, maybe more. Now I actually took mine back (the MSD) and tested a different one with the same results, so --

the only thing i can think of, and this is just a theory: Both Tiago and I have aftermarket Ignition Modules under the coilpacks. meaning we didnt buy AC Delco or from GM. Could this be a problem? I'm thinking its possible that the aftermarket ones, are either the 3.8 ignition module repackaged (cause it works) or the 3400 ignition module (cause its a similar engine) repackaged to work with the 3.4L engine.

or am i talking out of my a$$?

anyway. this is an interesting problem. id like to know if my box is fried too. cause if it is, in the trash it goes. Cant return it to PAW anymore. and when i called MSD, they told me that it's probably something i did wrong. who knows. hope someone can help Tiago cause in the process they'll be helping me too.

hows my theory sound?

-R

[Tiago]

update, damn thing still hesitates without the msd....msd makes it much worse though .

[v6maro]

<blockquote>quote:</font><hr>Originally posted by Tiago NOS'd Bird:
update, damn thing still hesitates without the msd....msd makes it much worse though .<hr></blockquote>

I had this same problem when I had my MSD, it was actually one of the CIU's.
pull them off, and check the prongs underneath where they plug into the stock harness, one of the metal prongs on mine was dangling there, so I had MSD send me a new one, and then it ran perfect.
Because the prong was loose/broken, it made the car run like *** (hesitating) w/o the msd even hooked up. good luck
-Steve

[Tiago]

thats possible, but damn, I didnt change anything on it, it was on the car and worked for months, how would it break all of the sudden? might as well check

[Tiago]

changed plugs, and once again they were snow white, I keep turning the FP up, but the last 3 sets of plugs have been LEAN looking, wtf is going on....fuel pump death ...new hope to fix car....

[v6maro]

<blockquote>quote:</font><hr>Originally posted by Tiago NOS'd Bird:
thats possible, but damn, I didnt change anything on it, it was on the car and worked for months, how would it break all of the sudden? might as well check <hr></blockquote>

I know, thats what I said, but I figured it was from the vibration from the engine.
-Steve

[Ironman24]

I have seen the same burnt coil pack spots you are talking about but the coils are working fine, #1 was burned real bad.

When my MSD died it was instant death, a huge backfire while driving and killed the car, coasted off the road, put bypass plug in and I was good to go. Second time same thing with a little smoke from under the hood. I'm still convinced it was the Accel coils causing the problems. I'm on my 3rd MSD and back to stock coils with no problems.

Sounds like you are having some fuel issues? I just fixed my fuel problems with locking up the injectors. I thought it was ignition at first and replaced everyting and removed the MSD. But it turned out to be fuel instead of ignition. The fuel/ignition have very similar symptoms.

[southern94]

i have been installing my msd dis-4 today and got it all wired up and now with the msd it will not send a spark and with it bypassed it chokes like it is missing cylinders and won't idle but like 2 sec.

tiago said to check my wireing but i went over it 4 times and everything is right anyone have any idea what could be going on?

[Tiago]

maybe what we were talkiong about on this post, the wiring seems to not work on some cars, strange

[Magnus]

southern94, double check the leads on the coils again... I remember SixVi6 telling me that on his 3.4 they weren't all the same.. One of the coil packs was reversed.

[southern94]

well guys i took the ciu's off disconnected the msd put the coils back on and i still have probs. sounds like i am missing a cylinder back fireing and wont idle acts like it's cranked but when i stop turning the key it cuts off :( i have to get this fixed damnit i got to drive back to college soon as in a week and in the meantime have not transportation to get my stuff together :mad:

[v6maro]

<blockquote>quote:</font><hr>Originally posted by southern94:
i have been installing my msd dis-4 today and got it all wired up and now with the msd it will not send a spark and with it bypassed it chokes like it is missing cylinders and won't idle but like 2 sec.

tiago said to check my wireing but i went over it 4 times and everything is right anyone have any idea what could be going on?<hr></blockquote>

I had the same problem
it's the wiring if the motor runs fine.
What i did was took an Ohm meter and checked to see which one had the +12v power supply, they were different than what i had from this board.
then it worked fine.
-Steve

[southern94]

ok went out this morning took coils off wipped em off put em back on carefully placed each plug wire back on made sure plug wire was tight on coils and spark plug lil lose on one plug and it fired right up i may have just had a plug wire on the wrong coil the whole dang time

*update*

hooked up the ciu's car runs fine with the by pass but will not send a spark when connected to the msd

v6maro you said that the diagram off this board did not work for you that you changed something could you please tell me what it was that you did this is the diagram i went by


http://tiago.phxchevy.com/MSD.html

[ August 01, 2002: Message edited by: southern94 ]</p>

[Tiago]

<blockquote>quote:</font><hr>Originally posted by southern94:
ok went out this morning took coils off wipped em off put em back on carefully placed each plug wire back on made sure plug wire was tight on coils and spark plug lil lose on one plug and it fired right up i may have just had a plug wire on the wrong coil the whole dang time<hr></blockquote>


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