No one can figure this out, spark is wierd

[young_withboost]

Hey i was hoping that one of you guys could help, i just built my motor, my car is a 95 but the engine now is a 97-99 the only difference being the cam sensor in know but my car is sparking on 2 cylinders it wont start, its at redline performance right now and they cant figure out the problem either, i have the cam sensor wired up right i hacked the plug and wired it up right to the other cam sensor, do you guys have any ideas im goin broke with this shop bill. thanks

 

[McFox]

The cam sensor from 97-99 changed. Something about inverted, I'm not entirely sure I just know they are different. Its kind of hard to understand what you did. However if your swapping blocks like that you need to keep all the old sensors off of the 95 block and put them on the new 97 block. I'm currently doing the exact same thing. If you have the 97 cam sensor on the block now, swap it and see if that fixes your problem.

 

[Old Mitsu Tech]

I can only give suggestions. If you have spark on 2 cylinders and you have good 12 volts to both coils I would hook a test light to the positive side of the battery and check the "bad" coil to see if it winks when you crank the engine. If it does and you have no spark then it's likely a coil. I pretty much doubt that is the case as I almost never replace coils on these. I more likely think it's a cam sensor or bad connection. That's where I would look first.

Good Luck

 

[young_withboost]

Yea i got a friend around here with a gst too and i tried his coil pack in my car still dosent fire, and im using the 97-99 cam sensor because i have cam gears on my new setup and the ones i got you cant use the 95-96 cam sensor on because it runs on the hahl effect that the new cam gears dont have......

 

[young_withboost]

Can noone help me? Nobody had a problem like this before, I really need to get my car running so any help is good thanks

 

[Old Mitsu Tech]

Did you test to see if you had bat voltage at both coils? Did you reverse your probe and test to see if you had a flashing light when cranking? You have to put the ground on your test light on the positive battery cable to check for grounding by the transistor. If all else fails and you are somewhat of a gambler, try a cam sensor. These have a relative high rate of failure compared to other items.

Good Luck

 

[McFox]

and im using the 97-99 cam sensor

Please someone feel free to step in and correct me where I'm wrong.

However from what I know you can't use the 97-99 cam sensor on a 95-96 block. In 97 the cam sensor was different (inverted or something?) and unable to work on a 95-96 unless you did some special work to the ECU. So I believe your options are as follows.

1. Get a 97 ECU and replace all sensors on your block to 97-99 sensors
2. Put your old cam gears back on and old sensors.

Again this is what I've gathered from reading myself. If I'm wrong someone please correct me.

 

[architechnik]

There is very little information in the description, which makes it REAL hard to pinpoint the problem. If you have a conflict between the new engine requiring specific sensors and the ECU not being able to match, I would say replace the ECU. You may even be able to trade at a pull-yer-part yard for only a couple of bucks.

As McFox mentioned, do you have all the sensors from the new engine or were the transferred from the '95?

 

[SRiz]

ok we just did this to a customers car... he had a 1997 GST and we put on a 1995 gst head with 1995 gst cam angle sensor... assuming you have the wiring right, inverted means the coils are inverted for the spark plugs.


stock

coil.. (4)(1)(2)(3)
plugs(4)(3)(2)(1)


inverted

coil.. (3)(2)(1)(4)
plugs(4)(3)(2)(1)


SOOOOO basically, take the 4 spark plug wires that go into the coil and instead of putting them in the normal order put them in backwards order... Should be good to go!!!

 

[architechnik]

Is that correct, samnumba1?! I thought inverted on the sensor just meant that the signals were inverted, not the actual firing order.
So the coil pack is actually the inverted part?

 

[Turboeagletalon]

no the fireing order on the cooil pack is. it;'s like takeing of the coil pack wires on the back of it amd switching them from forwards to backwords

 

[SRiz]

yup what he says... we have done this a couple times at my shop always works

 

[young_withboost]

Well i did my research when it came to this and i already tried the other spark plug sequence and it did the same thing, But just so there is no confusion on my car, the ONLY thing that is different is the cam angle sensor, the block was exactly the same as my old one as they all are the only thing that changed over the years was the ecu and the cam sensor, but i guess i could always try putting the old cam gear back on the intake side?

 

[Purevil]

Did you test the coil like "Old Mitsu Tech" suggested? If a coil is bad then you will get spark to only 2 plugs.

 

[Bizarre]

If a coil is not a problem, check your power transistor. If you can get a hand on one off of a buddy you can swap it temporarily to see if it's the problem, do so.

 

[Eastwood95]

You could also try a 97-99 ECU. Its a quick swap and will eliminate another potential problem.

My guess is the same as above, the CAS, bad connection, or inverted spark order.