Misfire at 3K
 

Just developed a missfiire at around 3K.

I'm thinking it could be plugs, injectors or coils.

How can I eliminate or any other suggestions?

Hi,

if you have access to a OBD tester, Durametric, or Porsche OBD test tool you can read out error code and check what's wrong with your engine. Coils and injectors are monitored.

If it's a coil problem, you can change the coil with one that produces no faults an see if the fault moves along with the faulty coil.

You can also check if have any leaks in the intake area. Just check with start pilot, or brake cleaner.

Regards
Markus

How do you know its truly a misfire?

Can you describe what is happening.

Check engine light?
Lack of power?
Stumble?

No CEL. When accelerating at 3k it stutters, hesitation & flat spot. It's not just that it fails to continue to accelerate evenly, it actually has multiple small jolts. Pretty hard to explain, the best way to describe it is a misfire until about 3.3k then everything is as normal.

It occurs until mild, moderate & full accelleration.

Hi,

do you have the missfire only when driving, or do you have the missfire also when the car stand still and you rev the engine up?

Regards

It's not noticeable when just revving while car is stationary

Unplug the mass air flow sensor... drive it around.. and report back to us :)

It sounds like what I am experiencing as well, unfortunately its not resolved yet but its intermittent in my case so I beginning to think it may be an electrical or ground problem of some sort.

You have to check a bunch of things to narrow it down, starting with the fault codes, MAF, air leaks and Fuel supply, AOS.

http://986forum.com/forums/performance-technical-chat/52071-how-diagnose-resolve-engine-issues-using-durametric.html

I've been swamped in car charging systems, bad batteries, alternators/regulators, etc for the last week. Most if not all that I've seen online experiencing/reporting low voltages also get those similar error codes (misfire here and there). Rule out the car's charging system while at it. MAF and as others have recommended are also good place to start looking