4200 Spyder 50k miles - Misfiring with no codes at all?

Hi,

My car is misfiring at the moment, and not registering any codes at all.

It had all the sparks replaced recently, oil is clean, lifters can be a bit tapety and it feels like it is retarding the ignition when putting your foot down at times, other times it fly's.

I haven't checked the MAF or intake, or checked for any air leaks yet, but wondered could this still be the coils even though it's not registering any codes, as I had two coils replaced earlier in the year.

Any thoughts where to start, as without any codes showing I am not too sure, other than to take it into an Indy of course..

Could well be coils. When you say it's not registering any codes, do you mean it's not showing a light, or you've plugged it into an OBDII reader, and that's saying there are no pending codes?

If the latter, you may just have to run it until it *does* throw a light, or get it on a proper diagnostic.

C

Thx Catman,

Raj did the clutch, flywheel and actuator and a few other bits recently, commenting on how it was a bit low on power, but we agreed I should run it for a while as it hadn;t been used in ages. It seemed to get better and power was pretty much restored, however, the miss is almost constant at the moment, and the OBDII reader isn't whowing any pending or current codes, where as when a coil went earlier in the year it picked up a misfire on cyl 3.

Time to go back to Raj for proper diagnosis?..

davidfo said:

Thx Catman,

Raj did the clutch, flywheel and actuator and a few other bits recently, commenting on how it was a bit low on power, but we agreed I should run it for a while as it hadn;t been used in ages. It seemed to get better and power was pretty much restored, however, the miss is almost constant at the moment, and the OBDII reader isn't whowing any pending or current codes, where as when a coil went earlier in the year it picked up a misfire on cyl 3.

Time to go back to Raj for proper diagnosis?..

Click to expand...

I would, yes. Coils would be a good bet though. They have a hard life.

C

Mine had a slight misfire this year. No OBD codes but on the sd2/sd3 it was traced to a wire fault on the air mass sensor. May be worth you checking the connections there.

Any other noises? Could it be a valve

Drive it some more - misfore codes take several cycles to appear.

What are your fuel trims? Also worth shoving it on an emissions tester - if it is misfiring then there will be tons of hydrocarbons in the exhaust.

Stuck/plugged injector won't show code. Standing for long can cause that. Use some injector cleaner and do "Italian tune up".