random misfires

[2001 greenGT]

hi guys i just put comp cams xe268h cams in my car and changed the plugs to bosch i havent gotten the car tuned yet but it still runs fine with the stock tune but when i try to start it i have to pump the gas just to keep it from stalling when i put the sct to it im getting a code for random engine misfires dose anyone know what the problem would be ive heard that i should only use motorcaft plugs but these parts have about 60 miles on them

 

[trinity_gt]

Did you remove the front cover when you installed the cams and if so, verify the torque on the crankshaft damper bolt.

 

[joshjwc9]

What is the actual code the SCT is giving you? Are you sure your COP boots are on your COP's all the way? You may have hurt the camshaft or crank position sensor too. Or the Crankshaft position sensor was not reinstalled correctly.

 

[2001 greenGT]

No everything is torqued and im sure I installed every thing correctly but when I started the car this morning no codes came up like I said it doesn't have a t

 

[2001 greenGT]

No everything is torqued and im sure I installed every thing correctly but when I started the car this morning no codes came up like I said it doesn't have a tune yet would that be the problem

 

[Dark04GT]

... like I said it doesn't have a tune yet would that be the problem

Yes.

 

[wmburns]

A couple of things to check.

Check the cam sensor's electrical connector.

After this much work, check for vacuum leaks.

Note, excessive slack in the the timing chains can casue random misfires. As well as a mistimed bank.

Confirm that the CKP sensor has been correctly installed in the timing cover (not loose). As Trinty has said, problems with the crank damper can cause this.

Cheap UD pulleys can also cause random misfires by messing with the quality of the CKP sensor signal.

Check the alternator for excessive AC ripple. Yes I know it's a long shot. But it's smart to rule it out.

Excessive EGR flow can cause random misfires. However, this seems unlikely in this case.

 

[2001 greenGT]

ok i changed the plugs and it stopped all most every now and then it hikups a little but i think its cause of no tune and i havent put the ud pullys on yet but they r from steeda soo they r good im gonna get the car tuned at mustang magic so well c also ill let every one know what happens as these cams i put in are the comp cams xe268h but i chose NOT to do valve springs

 

[Maxpowers]

Good luck and report back with some numbers.