Widespread failure or Ignition system throughout dsm community

[tsitalon1]

Hey Guys,

I need to do a survey. Please 1g guys only.

Here are my findings:

I have personally seen 3 ecu's provide a weak signal to the power transistor that causes a weak spark in the #2 and #3 cylinders. I need to see if anyone else is having these problems. I bet alot of our misfire issues are caused by this.

If people would indudge me:

Please pull the #2 plug wire while the car is at idle and see if it can arch from the plug wire to the valve cover when the wire is held aprox 1/4 to 1/2 an inch away from the valve cover. Also try #3 as well. (one at a time of course)

I believe you will find that the #1 and #4 arch a distance much further than #2 and #3.

I believe this might be a widespread dsm problem causing all sorts of tuning issues.

Please report back,

James

 

[psychlow]

I'll give this a try once my car runs again.

 

[tsitalon1]

Great..

The more people that respond, the more we can verify this problem and come up with a fix for everyone.


James

 

[tsitalon1]

Come on guys... It takes 30 secs to check this. We need this data.


James

 

[Merciless]

My car died about 30 miles from where I bought it yesterday with MAJOR misifre.

I brought it to Pruven Performance in Milford, CT and they did a quick preliminary check.

All four plugs have weaker than normal spark, but are all sparking. All four cylinders are getting fuel. And compression is healthy all across.

This is my first DSM. How does the ignition work on these things?

And where can I get a new OEM ignition?

 

[psychlow]

First, I'd check to make sure you're getting full output from your alternator.

After that, I'd try swapping out your coil pack with a known good unit.

 

[Merciless]

It's still at the shop.
I'm sure they'll know what to do with it.

I'll report back when I know more.

 

[tbTalonES94]

I have conciderably weaker spark on cylinders 1 and 4. The spark is slow and irratic compared to the fast and steady spark of cylinders 2 and 3. Could this just be our Ignitor packs? Can they cause a coil to be weak but the other good?

 

[R3dR]

On our cars 92-99 we have the same basic system, we use a waste spark system.
1-4 are the same coil
2-3 are the same coil

We use a unified ignighter that fires both coils as needed.

The ignighter does not care what coil its firing and will not fire them differantly (unless you have a wiring issue between the ignighter and coils)

If you have weak spark in 1-4 or 2-3 and not in both then you most likely have a failure on that coil. (unless you have a wiring issue between the ignighter and coils)

 

[dave99gst]

i would think if the spark was weak enough to matter it would be evidant on the plugs.

 

[tsitalon1]

If you have weak spark in 1-4 or 2-3 and not in both then you most likely have a failure on that coil. (unless you have a wiring issue between the ignighter and coils)

This is true, However, it is not the only thing that causes a weak signal. If you have swapped in a buddies coil, and transistor and still have an issue, chances are that ic4 in the ecu is providing to short of a pulse to the transistor which causes a weak spark.

In another words, Send the ecu to Dave Mertz to have it repaired.


James

 

[jott5555]

would a cop (coil on plug) setup help prevent this or a msd dis-2?

i think i have some misfire issues i havnt done a boost leak test yet but i beleive its ignition related.. everyone here on tuners says the dsm stock ignition system is very good for 100's of hp.. but i have yet to see any proof of that statement.

 

[dave99gst]

everyone here on tuners says the dsm stock ignition system is very good for 100's of hp.. but i have yet to see any proof of that statement.

you prob dont see proof of 80% of what people say, and that prob dont
stop you from agreeing on other things. Its just the consensus.

 

[tsitalon1]

would a cop (coil on plug) setup help prevent this or a msd dis-2?

i think i have some misfire issues i havnt done a boost leak test yet but i beleive its ignition related.. everyone here on tuners says the dsm stock ignition system is very good for 100's of hp.. but i have yet to see any proof of that statement.

A C.O.P. would not fix this issue because it gets its primary voltage from the same source (tansistitor) which gets it from the same (maybe bad) ecu.


A Msd dis-2 "might" resolve it, but being that the signal from the ecu would be a shorter duration than expected, you might get the same results. See, the duration of the signal from the ecu to the transistor charges up the primary coil on the ign coil. If the signal is short, the coil cannot charge fully, which results in a weak spark.

This is why I started this thread so that we as a group of people could help figure the root of some of these missfire issues. I was pretty disappointed when people wouldn't take 5 mins to test this out.

If you suspect the ecu, the only way to verify it would be to have a very competent dsm ecu shop (Dave Mertz) look at it. You would only see the ign signal with an o-scope.


So guys, Get your friends to test their shit and post their results, there is a poll here you know


James

 

[Generation1JeY]

i dont really understand what all u guys are saying, and sorry to get off topic, but i recently started a thread about my car because i have something seriously wrong with either my electrical system or my ecu. I cant tell at all whats wrong but if i run any boost pressure higher than 12lbs. At about 4krpm my car like seroiusly misfires, if i turn the boost down to maybe 10 like i have it now, i can maintain full boost all the way to redline but even so i notice a SERIOUS power drop on my top end power, and when i near the redline mark my car makes some very disturbing sounds. I'm afraid to take it passed 6krpm just because my car barely pulls at that range but also is just ridiculously loud and i fear its not healthy to take it that high at its current condition.

I think it has something to do with what u guys are talking about maybe my plug wires are not giving me spark at high rpms or massive boost pressure, or something with my ecu or coil pack or igition? i really have no idea any help appreciated though.

 

[tsitalon1]

ok then,

1. Change plugs to Bpr7es Gap to 28
2. change wires
3. Change coil
4. Change transistor
5. Still not working.. try another ecu

Try these in this order. Please don't ask me what these parts are



James