misfire pcm excalabur 330hp... 400hrs

[laurie88]

changed plugs, fuel filters, fuel pumps, no o/heat , no prob starting, good fuel pressure 60psi, changed gas, checked resistance on leads all same,good comprression but under load at just 1500rpm everytime starts misfire bad,
changed exhaiust maniflold just before this misfire issue, could it be related to exhaust any ideas anybody thanks

[thedude]

What about the distributor cap and rotor? Are you certain no plug wires are crossed?

[causewayskiier]

missfire

I had the same problem with my '07 with 330 HP. I finally changed the rotor cap and that seems to have solved the problem.

[georges]

missfire

I had he same problem on a '07 211. After changing plugs, wires, etc. the dealer used his computer with a lake test. The timing was off at slow speeds. He made an adjustment which corrected the problem. Good Luck!

[causewayskiier]

missfire

I had the same problem with my '07 with 330 HP. I finally changed the rotor cap and that seems to have solved the problem.

[laurie88]

missfire

thanks guys

i have some questions

i thought the timing was fixed and non adjustable?? i do not have delaer here can you pls give me the phone No of your dealer tx


In terms of the rotor cap, is this the distributor cap and if so you unscewed it from the disrt housing (2 screws) and just replaced cap instead of whole disrt body assy.

pls advise

[KenG]

thanks guys

i have some questions

i thought the timing was fixed and non adjustable?? i do not have delaer here can you pls give me the phone No of your dealer tx


In terms of the rotor cap, is this the distributor cap and if so you unscewed it from the disrt housing (2 screws) and just replaced cap instead of whole disrt body assy.

pls advise

The rotor is under the distributor cap. Remove screws and remove distributor cap, the rotor is then visible. I'd replace both.

[wakebrdr38]

Had the same exact issue a couple weeks ago. Drove me crazy trouble shooting everything. I changed everything just like you. The very last thing I did was change the cap and rotor and problem completely solved! I had a lot of corrosion and the motor only had 350 hours on it. There was an issue with that GM motor and moisture collecting under the cap. I highly recommend going to O'reilly's to buy the replacement cap and rotor (I think it came to about $60) but it comes with a lifetime warranty. After I had heard about this problem with the distributor cap and no real fix for it I figured a lifetime warranty sounded great!

[DanielC]

The ignition timing is controlled by the computer. But the distributer has to set "close enough" so the rotor inside the cap is pointing to the correct terminal inside the distributer cap.

[laurie88]

misfire

thanks guys

if i change the distr casp and rotor is it just a csae of removing and replacing or is there sonme adjustment to be made and if so how is this done..cheers

[KenG]

thanks guys

if i change the distr casp and rotor is it just a csae of removing and replacing or is there sonme adjustment to be made and if so how is this done..cheers

Just a matter of replacing the parts. Obviously the plug wires NEED to go back in the right place.

[ffmedic74]

check your battery as well. If you arent getting enough voltage to the injectors they will not work correctly and do the same thing as you describe.

[scuff97]

If you replace the cap and rotor only there is no adjustment. if you move the complete distributor you will need to hook up diagnostic tolls to set the cam retard.

[thedude]

As mentioned above, just make sure of which wires go where by marking them 1-8, or however you want to mark them. Its a very easy job, 20 min max.

[laurie88]

engine misfire

thanks guys im goin to check the distr today.

did your engine warning light come on, my doesnt

i have the diagnostic tool also so i will give that a try, although since my warning light does not come on i do not know if the ECM will store any trouble codes (dtc)