350TPI wont start unless one injector unplugged
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Joined: Oct 2013
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From: Toronto, Ontario
Car: 90 GTA
Engine: 5.7L
Transmission: 700R4
Axle/Gears: 3.73
350TPI wont start unless one injector unplugged
My 90 GTA won't start unless one injector is unplugged. I have good spark and hear the fuel pump priming. I checked for power at both terminals of the injector plugs. Both wires have power. I think there is a short somewhere. Anyone else have a problem like this?
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From: Des Moines, Iowa
Car: 1991 Camaro RS yellow
Engine: was '91 V6, now '89 5.7/355 TPI
Transmission: 4 speed automatic
Axle/Gears: Moser 3.73 with zexel posi
Re: 350TPI wont start unless one injector unplugged
Check that leads are on correct injectors; easy to misconnect.
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From: Toronto, Ontario
Car: 90 GTA
Engine: 5.7L
Transmission: 700R4
Axle/Gears: 3.73
Re: 350TPI wont start unless one injector unplugged
it was running good the other day...parked it and won't fire up. the leads are in correct order.
Joined: Dec 2012
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From: Clarksville,TN
Car: 1989 GTA
Engine: 5.7 w/Paxton
Transmission: 700R4
Axle/Gears: 3.27
Re: 350TPI wont start unless one injector unplugged
ohm test injectors: pull plugs off injectors... then place leads from voltmeter on each side of the two prongs inside the injector. should be around 16ohms if stock.... southbayfuelinjectors.com/ on here is the go to for some nice replacements if needed.
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From: Tracy, CA
Car: '87 IROC
Engine: LB9
Transmission: TH700R4
Re: 350TPI wont start unless one injector unplugged
Does the engine start no matter which injector is unplugged?
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From: Toronto, Ontario
Car: 90 GTA
Engine: 5.7L
Transmission: 700R4
Axle/Gears: 3.73
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From: Not in Kansas anymore
Car: 82 Z28
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Re: 350TPI wont start unless one injector unplugged
And that effects what exactly ???????
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From: Florida
Car: 1987 Trans am
Engine: 350 Vortec Stealth Ram
Transmission: T-5
Axle/Gears: 02 SS Torsen Zexel 3.42
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Re: 350TPI wont start unless one injector unplugged
Mr.Bounge, if these are still the original Multec injectors, just replace them. Don't bother to measure them, they are bad (the coils short out).
RBob.
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From: SC
Car: '87 IROC-Z | '99 SS
Engine: LB9 | LS1
Transmission: 700R4 | T56
Re: 350TPI wont start unless one injector unplugged
My injectors were in the 16 ohm range, all of them. Replaced them with a set from SouthBay, all good. Don't even waste your time with those original injectors.
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Re: 350TPI wont start unless one injector unplugged
Have you hooked a scan tool to your car to do any diagnostics? Did you check that your coolant temp sensor is functioning properly? If the CTS is bad, the ECU will think it's -40* outside and will add way too much fuel at startup. Unplugging an injector may be offsetting that massive fuel enrichment enough to let the vehicle start.
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From: Toronto, Ontario
Car: 90 GTA
Engine: 5.7L
Transmission: 700R4
Axle/Gears: 3.73
Re: 350TPI wont start unless one injector unplugged
Have you hooked a scan tool to your car to do any diagnostics? Did you check that your coolant temp sensor is functioning properly? If the CTS is bad, the ECU will think it's -40* outside and will add way too much fuel at startup. Unplugging an injector may be offsetting that massive fuel enrichment enough to let the vehicle start.
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From: Toronto, Ontario
Car: 90 GTA
Engine: 5.7L
Transmission: 700R4
Axle/Gears: 3.73
Re: 350TPI wont start unless one injector unplugged
looking at injectors from south bay....price is $165.99 /8
is that the price for all 8 injectors or for each one. sorry if I sound confused, but I bought my delco rebuilts for $75 each
is that the price for all 8 injectors or for each one. sorry if I sound confused, but I bought my delco rebuilts for $75 each
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From: Round Rock, TX
Car: 1988 Firbird formula 350
Engine: 5.7L TPI
Transmission: 700R4
Axle/Gears: 3.27 Nine Bolt
Re: 350TPI wont start unless one injector unplugged
Yes, that is the price for a set of rebuilt Bosch III injectors.
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From: SC
Car: '87 IROC-Z | '99 SS
Engine: LB9 | LS1
Transmission: 700R4 | T56
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From: Florida
Car: 1987 Trans am
Engine: 350 Vortec Stealth Ram
Transmission: T-5
Axle/Gears: 02 SS Torsen Zexel 3.42
Re: 350TPI wont start unless one injector unplugged
As said above. Can't go wrong with them either. The warranty and support from SouthBay makes it worth while. Not to mention those injectors are great.
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From: SC
Car: '87 IROC-Z | '99 SS
Engine: LB9 | LS1
Transmission: 700R4 | T56
Re: 350TPI wont start unless one injector unplugged
I second that. I also replaced the fuel pressure regulator diaphragm while I had it apart, and bought the fuel pressure regulator diaphragm from SouthBay as they sell it as well.
Re: 350TPI wont start unless one injector unplugged
Thank you everyone! Mr. Bounge, the cost is for the set of (8) injectors.
They come with a 3 year warranty, and yes they are $165.99 however tgo members receive a 10% discount using the promo code tg11
If you have any questions please give us a shout at the shop.
516-442-4707
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From: Toronto, Ontario
Car: 90 GTA
Engine: 5.7L
Transmission: 700R4
Axle/Gears: 3.73
Re: 350TPI wont start unless one injector unplugged
something that I forgot to mention. when I unplug cylinder #1 injector, the engine starts. I used a needle nose pliers and grounded the terminals together and the engine stalls. does anyone have a clue whats going on?
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From: Bluegrass State
Car: 85 Trans Am
Engine: LB9
Transmission: Finally Fixed (T5)
Axle/Gears: 3.27
Re: 350TPI wont start unless one injector unplugged
Yeah...the ECM is detecting the same type of fault, when you create a zero resistance connection across those two terminals, as your bad injector. Its shutting down the all of the injectors to protect itself.
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From: Chasing Electrons
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Re: 350TPI wont start unless one injector unplugged
Contrary to popular belief there is no self-protection circuity in the ECM.
As I previously posted, just replace the injectors, they are bad. Even though they are not the original Multec injectors, there is no difference between having the originals in there or having re-man Multec injectors in there.
They fail by the coils shorting and going through a "re-man" process won't do a thing about that failure. It will happen, which it has on at least two of the "new" injectors.
RBob.
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