Runs bad

[jerryjerry05]

2006 225 VZ225TLR
First what's the fuel pump pressure supposed to be? I test it and it comes out at 55#
Comp 120/6, spark ok.
Start it and it idles, when put in gear and accelerated it revs up and down fast again and again and will smooth out when put back in neutral.
Does it every time shifted into gear.
What should I look for?
Thanks

[99yam40]

z stands for high pressure, so your 55 is way low

[boscoe99]

I suspect that he is measuring the medium pressure fuel pump. Which is nominally 51 psi.

[jerryjerry05]

TPS???

Checking the tps and it shows 5 volts into the tps.

From what I understand it's supposed to be .5 volts not 5.0 volts

What would cause the voltage to go up so high?

That's probably the reason the motor runs bad(see other post).

Thanks,

[boscoe99]

5 volts TO the TPS is correct. On the Orange wire.

0.56 volts out of the Pink wire at idle.

[Keithbaja]

Really simple. Cars, boat motors, Trucks. All mostly use a 5VDC ref. Signal. Aka, source. A good trick is save a cell phone 110AC charger that outputs 5VDC. dime a dozen and good test tool. Also dont let any Solar guy (Idiots) tell you you need inverter to charge your laptop off grid...Wrong, Wrong,, Wrong !!!

[jerryjerry05]

99Yam, Bosco I measured the pump pressure at the schrader valve on the VST tank. 55#
If 55is low?? what should it be?

I understand how I probably measured the TPS wrong. Will try again.
THANKS!!

[99yam40]

post #3

I thought you were talking about rail pressure, but I was wrong

[boscoe99]

99Yam, Bosco I measured the pump pressure at the schrader valve on the VST tank. 55#
If 55is low?? what should it be?

I understand how I probably measured the TPS wrong. Will try again.
THANKS!!

51 psi or better. Pressure is not critical. All that pump is doing is feeding gasoline to the high pressure fuel pumps.