Popping at 3/4 and wot

[IMQUIK]

When I give it the 3/4 throttle or wot it pops back thru the intake. Coil, wires, plugs, etc are all less than a year old. Thanks for any input. Mike

 

[TurboBuRick]

Sounds like a possible worn cam lobe.

 

[IMQUIK]

Would it do it sometimes and then not?

 

[rodman99999]

Make sure all your turbo/intercooler/throttle body hose clamps are tight, and look around for vacuum leaks or a blown off line.

 

[bmackinnon]

Sounds like a possible worn cam lobe.

Sounds MORE like:
a) 'Lean' pop, due to fuel pump failing (or clogged filter).... need to VERIFY!! fuel pressure is rising from base 1 lb for every lb of boost....and not falling off... ie... 43 psi base + 15 psi boost = 58 psi fuel press at wot.... (adjust numbers for your base/max boost)....

OR

b) Coil Pack is marginal/failing..... new(er) most certainly doesn't necessarily mean good.... need Casper's tester or KNOWN good replacement to swap for diagnostic purposes...

probably 90-95% of 3/4-WOT popping problems are due to one of the above 2 causes.... if it's (a) above, then you better quit romping on it, cause the next pop you hear will likely be your headgaskets blowing....

 

[bmackinnon]

Would it do it sometimes and then not?

not if it was the cam.... most definitely if it's what I said above... coil pack gets hot, weak, and engine starts popping wot.... same w/fuel pump... works ok at first, starts loosing ummmph after a few minutes run time.... been there done that.... a couple times.... for both reasons.... :frown:

 

[IMQUIK]

Thanks for the help, Mike

 

[turbojd]

I would start with the basics first, check coilpack even though you said it's only a year old and go from there, verify proper fuel pressure at the rail, check the simple stuff first.