ignition issues

[josherino]

I have a hiccup at idle. I have replaced my spark plugs, used a volt meter to test my plug wires and just put a new coil pack in. What else could this be?

 

[andymoraitis]

You might want to make sure that your plug gap is correct and that the plugs haven't loaded up from being run at too wide a gap. For your purposes .028-.030 would work fine. I had a similar issue cause idle misfire so check that first and then yell back at us.

Hope that helps,

Andy

 

[josherino]

they have been gapped at .028, I am not sure if I would call it a misfire, but a quick change in exhaust tone like a hiccup

 

[andymoraitis]

I get that every once in a while. Does this also happen under WOT when you're mashing it under full boost? Are there any other hesitations under load?

Just wondering,

Andy

 

[josherino]

not only do I have hiccups at idle but under full load my car does a very extreme lurch, i am able to drive through it, and when I do it does it about 3 to 4 times before redline

 

[5150DSM]

Sounds more like a boost leak as opposed to an electrical issue. Possibly something small like TB shaft seals or a torn vacuum line. I would run a boost leak test and see if you can find any leaks.
Even a small vacuum leak can play major havoc with the performance of the motor.
Aloha

 

[andymoraitis]

I'd have to agree with the above assessment and would go through the following checklist:

1. Boost leaks
2. Vacuum leans
3. Fuel pump - fuel pressure solenoid
4. Inspect ECU caps

Please have a look at all of those and let us know what you find.

Andy