AnnivSS

2002 Camaro SS A4 Stock Engine/Trans
SLP Intake Lid
Ported Throttle Body
GMPP 6.0L Plug Wires
Factory Spec AC Delco Plugs
Deatschwerks DW300.1 Fuel Pump
111,000 Miles

Problem: On hard to full acceleration there is an audible knock/ping noise with no loss in power,sluggish behavoir, or any other problems of the like. With a fuel pressure gauge taped to the windshield the vehicle drops to 51psi on accel. 58-60 psi at idle.


Attempted Remedies:

New Fuel Pump
New Plugs
New Fuel Filter
New Air Filter
3 Different Known Good MAF's (Non-Ported, Factory Screen)
Fuel Injectors removed and flow tested to be good.


Vehicle is at APS Automotive here in Oklahoma City and Bo is taking good care of it but were both a tad stumped as to where we could go from here. Vehicle has no codes. The only other I can think of is possibly knock sensors, however im not sure why the knock sensors would cause it to lose fuel pressure. It seems to me if anything a knock sensor reading false knock would add fuel. And correct me if im wrong but fuel pressure should be constant even with changes in fuel volume should it not? Any insight is appreciated.

MM98

iTrader: (13)

If the knock sensors are in good working order, they should pull timing if knock is detected.. You might look in your intake & see if it's coated with oil, that would cause knock if you're getting oil in your intake charge.. If so, time to upgrade your pcv.. I'm not sure what that pump is rated at & if dropping to 51psi is "acceptable" or not.. Does it show a lean condition on the dyno at APS & what is the injector duty cycle at? Deatschwerks is here in Okc, have you called them & explained your situation?

AnnivSS

Well Im not real versed in this field but im assuming since hes telling me its losing fuel pressure and that its at 51psi at full throttle that 51psi is unacceptable. Bo has spoken to Mike Deatsch himself and couldnt come up with anymore ideas. I havent seen the car in 3 weeks and I havent looked inside the intake manifold to be perfectly honest, so i couldnt vouch for that. And as to my understanding on a near stock car it shouldnt "need" a pcv upgrade correct?

MM98

iTrader: (13)

No, these cars PCV systems are horrible, modded or not.. Does Deatschwerks offer any kinda warranty on their pumps?

AnnivSS

3 year warranty. The pump is good. A bad pcv system might explain the knock but doesnt explain the losing of fuel pressure.


Btw: I just realized are you the same Mike that worked in the parts department at Heitz?

O2Form

Its gonna knock with low fuel pressure. When you replaced the fuel pump did you replace the regulator also? Try cracking the gas cap open and then drive it wot.