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FUEL INJECTOR TROUBLE?

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Old May 29, 2006 | 08:13 PM
  #1  
TABBOO's Avatar
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From: CANTON, OHIO
Car: 87 T/A
Engine: 305 TPI
Transmission: 700R4
FUEL INJECTOR TROUBLE?

I have an 87 TA 305 TPI. After I run the car & shut it off I smell gas, I don't see any gas & if I restart it is harder to start & acts as if it is flooded> I think my injectors are leaking by. I have read about putting a fuel guage on & blocking the supply & return lines. How do you block off the lines?
If the injectors are bad is it better to get new or have rich at cruznperformance clean the original ones? The car only has 30,000 original miles on it but it is stored every winter & I had a new fuel pump put on last summer ( maybe some crap got stirred up & clogged them). If anybody has some suggestions on what brand 19# injectors to go with I would welcome the advice!!!
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Old May 29, 2006 | 08:42 PM
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From: houston
Car: 83 POS monte carlo 2015 chevy P/U
Engine: 92 5.7 tpi 5.3
Transmission: 700r4 6L60E
Axle/Gears: 2.42 too high
the first thing i would check is the fuel pressure regulator.
its common for them to start leaking.
pull the vacuum hose off the regulator & see if the vacuum hose & fitting looks wet. if its dry, with vacuum hose still off start the motor up & watch the hose fitting for any fuel. if it still hasn't shown any signs of leaking, turn the motor off & check it again.
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Old May 29, 2006 | 11:53 PM
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When they say block off the lines, one way to blow junk from the pressure regulator is this. Pinch the return line with a locking pliers, and the pump will shoot up to max pressure, and dead-head. The excess pressure will blow any junk off of the regualtor and flush it into the return line. That's right off the Street & Performance TPI info video!
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Old May 31, 2006 | 03:40 PM
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From: CANTON, OHIO
Car: 87 T/A
Engine: 305 TPI
Transmission: 700R4
Will a leaking fuel pressure regulator make the car start like it is flooded? It cranks longer than normal & when it starts it sounds like a motor that is flooded (stumbles a little then takes off like when you start a lawn mower that you primed with too much fuel). Do you just block off the return line for a pressure leak down test too?Where do you get the street & performance Tpi info video?
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Old May 31, 2006 | 07:29 PM
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From: houston
Car: 83 POS monte carlo 2015 chevy P/U
Engine: 92 5.7 tpi 5.3
Transmission: 700r4 6L60E
Axle/Gears: 2.42 too high
yes, when you have a leaking fuek pressure regulator it dumps raw gas right into the intake manifold which can cause longer than normal cranking.
if bad enough it can also cause a bent rod or split the cylinder wall by filling a cylinder with fuel.
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Old May 31, 2006 | 08:05 PM
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From: Clearfield,Utah
Car: 1987 IROC, 1989 IROC
Engine: built 305, stock 305 tpi
Transmission: Corvette 700r4, t-5
Axle/Gears: 4.10 posi, 3.08 posi
since when can you "split" a cylinder by filling it with to much fuel?
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Old May 31, 2006 | 08:45 PM
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From: houston
Car: 83 POS monte carlo 2015 chevy P/U
Engine: 92 5.7 tpi 5.3
Transmission: 700r4 6L60E
Axle/Gears: 2.42 too high
since always
normally you won't split a cylinder with fuel by cranking, but if a cylinder is a little thin in 1 spot, which any motor casting can have, & you have a good enough starter & we know liquid fuel can't be compressed, something is going to give.
99.9% of the time when something gets hurt, its the rod, but when you pull a motor down that was you know was locked up by fuel, has gas in the coolant & you find a cylinder with a crack in it, what happened?
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Old Jun 3, 2006 | 10:39 AM
  #8  
TABBOO's Avatar
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From: CANTON, OHIO
Car: 87 T/A
Engine: 305 TPI
Transmission: 700R4
Which side is the return line? Will blocking this off make a leaking fuel pressure regulator show up more when the system is pressurized?[B]I figured[out which line was the return sorry for the question it was late at night when I posted!!! See next post for info. /B]

Last edited by TABBOO; Jun 4, 2006 at 02:07 PM.
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Old Jun 4, 2006 | 02:01 PM
  #9  
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From: CANTON, OHIO
Car: 87 T/A
Engine: 305 TPI
Transmission: 700R4
I checked the fuel pressure regulator, I blocked off the return line turned on the ignition(just the power to run the pump no starting) I let the pressure build then I unblocked the line to flush any junk into the return. I neither saw nor smelled gas from the regulator.
I then started the car & took off the vacuum hose but still nothing. I repeated this 1 more time to make sure.
I did notice when I ran the car & idled in drive that the idle would fluctuate every 5 seconds or so. I am still wondering about leaking injectors due to after running the car & restarting after it sits awhile it is hard to start.
Anybody have any ideas? Sorry for the long post but I wanted to explain the problem fully.
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Old Jun 4, 2006 | 02:50 PM
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From: edge of the map
Car: red one
Engine: on the floor
Transmission: next to engine
Axle/Gears: the ones that turn
Test the injectors: Put a fuel press gage on the fuel rail, ingage the pump should be about 40 to 47 PSI. Turn off the pump and watch the gage, it should only drop a little 10 PSI max, keep watching, if the PSI falls FAST, or falls to...0...within 5 or 10 min. you might have leaking injectors.

good luck
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Old Jun 4, 2006 | 02:59 PM
  #11  
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From: Central California Coast SM
Car: 91 Z28 24th Anniversary
Engine: L98
Transmission: Auto
Axle/Gears: Posi 3.23
Try cycling the key 3 or 4 times before starting. If it starts right up, could be the fuel pump leaking off. The fuel pump also should hold pressure.
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Old Jun 6, 2006 | 07:59 PM
  #12  
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From: CANTON, OHIO
Car: 87 T/A
Engine: 305 TPI
Transmission: 700R4
I will have to buy a fuel pressure guage & test for leak down. I will probaly test the whole system & then block off the feed & return fuel lines to check just the injectors.
The fuel pump is brand new so I don't think it is bleeding off pressue. The symtoms when it starts hard are more like that of too much fuel.
I will try to work on it this weekend.
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