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View Full Version : fuel pressure anyone?



silversc90
08-17-2003, 04:37 PM
38lbs key on engine off, 32lbs at idle, gauge will spike at about 40lbs by blipping the throttle. motor is stock. does this seem right? the car is still down on power, seems lazy off the line and through the rpm range. a friend scanned it and found knock sensor. we replaced it, along with the cam sensor. some other symptons are surging idle when cold. the oringinal maf has been put back on.

MIKE 38sc
08-17-2003, 06:12 PM
Fuel pressure sounds about right.
The surging sounds like a vac leak and that could explain why you got a code for the knock sensor as well. The lean mixture could be causing slight detonation and the knock sensor is pulling timing to stop detonation and that drops your power level.

The knock sensor code was telling you that the knock sensor was detecting knock(detonation) not telling you the sensor was bad.

silversc90
08-18-2003, 12:27 AM
It actually started about a month ago after roller rockers were installed I had a tick on the pass. bank (Car had more top end grunt during this time). Took off that valve cover found the ticker and the sled was a hair too tall. So we cut down the sled and the ticking stopped but then couple days later it starts to feel slower so I took it to a test and tune and could only pull a 14.9 out of it. About 2 weeks ago it started stutering at startup and cold idle until you drove about 4-8 miles then it quit the stutering but still feels slow. Oh yeah the exhuast note has changed a little too.

MIKE 38sc
08-18-2003, 12:31 AM
What did you set the lifter preload at when you first installed the roller rockers?

silversc90
08-18-2003, 10:41 AM
the cam was rotated to base circle and the the rocker was tightened to 26-28 foot lbs. the pedestal was .o35 to tall. they are non adjustables.

silversc90
08-18-2003, 12:22 PM
Shimmed up #2 Intake and Exhuast and she runs perfect now.:D