Mr.Bounge

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?

James Sutton

iTrader: (2)

Check that leads are on correct injectors; easy to misconnect.

Mr.Bounge

it was running good the other day...parked it and won't fire up. the leads are in correct order.

MrPackstin

iTrader: (9)

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.

paulo57509

Does the engine start no matter which injector is unplugged?

Mr.Bounge

Does not start when injector for #1 cylinder plugged in...it starts right up when its unplugged. Haven't checked injector resistance yet.

vetteoz

iTrader: (13)

So that injector must be faulty. if the ECM sees a bad injector it shuts down all the injectors in that bank

And that effects what exactly ???????

L98GTA87

iTrader: (1)

There is no specific order. Just bank 1 and 2, drivers side-passenger side.

RBob

iTrader: (1)

Not even then, there is only one injector driver in the ECM ('7730 in this case). It is batch fire.

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.

IROCgiraffe

iTrader: (3)

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.

Jim85IROC

iTrader: (2)

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.

Mr.Bounge

Just measured resistance in each injector.....cyl#1 is 0.6ohms and cyl#7 is 8.0ohms. The rest are around the 16ohm mark. I noticed the engine missing the last couple of weeks. I replaced all the injectors 3 years ago with rebuilt delco ones. I guess that was a huge mistake.

Mr.Bounge

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

lonestar7

iTrader: (1)

Yes, that is the price for a set of rebuilt Bosch III injectors.

IROCgiraffe

iTrader: (3)

Should be all (8).

L98GTA87

iTrader: (1)

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.

IROCgiraffe

iTrader: (3)

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.

southbay08

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

Mr.Bounge

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?

nomind

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.

RBob

iTrader: (1)

Don't do that, the injector driver has been under enough stress due to the nearly shorted #1 injector as it is. By shorting +12 volts to the injector driver, that is trying to provide a ground to fire all of the injectors, you are stressing the heck out of the driver.

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.