99 yukon missing

[lifted_yukon22]

99 Yukon 188xxx New plugs new wires cap and rotor new all ac delco. Cranks fine run fine only missing when on accelerating hard around 3000 rpm or going up a hill and it kicks down its getting 60-65 pounds of fuel pressure with key on. The rotor didn't seem to have excessive play.

 

[lifted_yukon22]

Could it possibly be a weak coil.

 

[retorq]

Could be, could be the the control module ...

 

[lifted_yukon22]

How would I go about checking either one.

---------- Post added at 05:52 AM ---------- Previous post was at 05:04 AM ----------

Got a p1345 code this morning but havr New crank sensor

 

[SunlitComet]

you dizzy hold down may have come loose and slighty offset itself. if not doable by yourself have a shop that can read CAM_RETARD zero it out and refasten the hold down. have them check the misfire history as well for any abnormally high misses compared to the others that can happen when it gets offset.

 

[lifted_yukon22]

Already did it, they told me it was -2 degrees. I'm going back next week and let him ride with the diagnostic tool plugged up and see what it says I believe the dizzy gear is worn. How much side to side play is acceptable in the dizzy shaft?

---------- Post added at 05:39 AM ---------- Previous post was at 05:38 AM ----------

It only does it while driving not siting in the yard reving up.

 

[SunlitComet]

what plug number and gap did you use?

 

[lifted_yukon22]

The gap was .060 and the plugs were acdelco that was recommended for my truck....

 

[SunlitComet]

ensure the cap fully seated. make sure your CAM_RETARD is correct(getting the p1345 code in pcm can take some time to get out of pending status if other issues like misfire detection occurs. and make sure you burp your wires boots so the air does not push them off. can you get a misfire history please.

 

[lifted_yukon22]

I am going Saturday after work get a snap on diagnostic scanner put on it maybe its a simple fix.

---------- Post added at 05:00 AM ---------- Previous post was at 04:55 AM ----------

I will post results, when I changes cap wires and plugs and all the rotor had more left and right play than I thought it should have...