LBZ: New cp3,still p0087!?!
- Thread starter Devon
- Start date
I'd get a 10 dollar pressure gauge on it forsure. another cheap test. I've had lift pumps not pump fuel, even though the pump motor was running. So you never really know until you check it out.
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I am just going to buy the indicator light from dmaxstore,then I'll know once my airdog drops below 5 psi or whatever it is.also be purchasing a stock shimmed valve
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Unless I over read it somewhere I didn't see where you said which fuel pressure regulator you used on your new cp3. Did it come with a new one on it?
Just to clarify, doing a return rate test and a bottle test are two different things. A bottle test just checks to see if fuel is leaking past the fuel pressure relief valve. A return rate test usually involves checking the return rate of the injectors. On LBZ and LLY motors, GM specifies that each injector should be tested individually. On the LB7 they have you run the CP3 return into a separate container and then run both injector returns into another container and measure the amount of fuel returned for a given amount of run time.
Anybody know eactly how to do a return rate test on an lbz. I read some people test them cranking on llys, but there is no way to crank without starting on lbzs...
I didn't get much of any fuel just cranking. I let it start and idle for 20 seconds each time. 1 and 4 are toast...
Alright good thing you don't need to just crank it... I don't think there is a way to crank without start on lbz. Where would one buy those measuring cups, I don't think theres any science class stores around here lol
I bought a used Kent Moore kit off of ebay. Simon found some Horse syringes at a feed store.... I think you will still need the brass fuel line adapters, or be real careful pulling the rubber lines off of the plastic nipples.
That's pretty telling for sure, thanks for the pics.
I got a set of (4) 100ml graduated cylinders off ebay (maybe $5 each). Instead of getting the Kent Moore injector nipples, I just took the right side injector return line (cheapest) and separated all the hoses from the injector T's. Then I plugged one side of each T (used a small screw to plug the line on one side) and hooked a rubber line from each (make sure all the lines are the same length) on the other side, put them into each of the graduated cylinders and idled the engine for 30 seconds exactly (that way I could compare readings from both sides). I ended up buying 2 return lines since I was concerned about cracking on the plastic T's, but if you wanted to go as cheap as possible you can just replace the right side return line.
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Pat, do you have a part number for the stock FPRV because I thought they still only sold them with the rail?
It would be handy to be able to get a new LBZ valve for my LLY.
Nevermind I found it:
98090186 - SENSOR F/INJN FUEL RL FUEL PRESS, (PART OF 3)
Looks like Huckstorf still has them alot cheaper direct from Bosch though.
Not sure what I was thinking, but that's not the FPRV part number above (it's the fuel rail sensor P/N).
This is the correct FPRV P/N for an LLY: 97358556
This is the correct FPRV P/N for an LBZ & LMM: 97371618
Oregon Fuel Injection also carries them separately if yours can't be shimmed anymore.
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