93 TBI 5.7 Pouring tons of raw fuel when key turned on

[Schurkey]

You've most-likely got grounded wires, or a defective ECM.

There is no condition of the coolant sensor that can cause this problem--open, shorted, or anywhere in-between.

 

[someotherguy]

I don't understand why someone would replace parts first instead of trying some very basic troubleshooting moves. Disconnecting the electrical plugs at the top of the injectors is about as easy as falling off a log, and will instantly determine whether the issue is electrical or mechanical. (The CTS is very, very, very unlikely to be a contributor to this issue.)

Richard

 

[Oldschooltruckdude]

Had several people say coolant sensor. I changed the oil as it had a fair amount of fuel in it, changed the plugs as they were black and a bit wet, and put a coolant sensor in it. Started it up and it ran very nicely once the excess fuel cleared out, and idled smooth. Let it get good and warmed up completely. Shut it off. Turned the key on. Immediately heard a loud clicking or buzzing sound and saw that the injectors were running wide open and dumping tons of fuel into the intake. Nice cone-shape spray. Shut it off quickly so as to not have to go through the whole clean-up process due to excess fuel.. It did need the plugs and oil change, it did not need a coolant sensor.

 

[MBski]

This sounds a little like the intermittent problem i had with the coolant temp sensor (the one that feeds the ECM, not the one that feeds the gauges). The GM scan tool showed it was reporting like -30 degrees at times which triggered the ECM to dump lots of fuel into the throrrle body. I think someone mentioned the CTS above--may be worth a look.

 

[Schurkey]

For ****'s sake...If the injectors are spraying WITHOUT a crank signal from the pickup coil/module, IT"S NOT THE COOLANT SENSOR.

The injectors are being improperly grounded--wire harness problem, or ECM problem; or the injectors are stuck open (really unlikely that both would stick at the same time.)

I don't understand why someone would replace parts first instead of trying some very basic troubleshooting moves. Disconnecting the electrical plugs at the top of the injectors is about as easy as falling off a log, and will instantly determine whether the issue is electrical or mechanical. (The CTS is very, very, very unlikely to be a contributor to this issue.)

Hell, yes.

 

[Erik the Awful]

Had several people say coolant sensor.

They aren't paying for your parts. Talk is cheap. Listen to Schurkey and disconnect the electrical plugs.

 

[PlayingWithTBI]

^^^X2, here's a drawing from an 88 which may help. If after disconnecting the injectors' connectors, and it stops spraying, you can hook them back up and then, disconnect the 4-wire connector on the ICM to see if it's giving the ECM false DRPs.

You must be registered for see images attach

 

[evilunclegrimace]

Some peoples kids.

 

[Big G]

Common sense is not common

 

[Mech_Lyfe]

@Oldschooltruckdude this sounds similar to what I did when I did a motor swap on my suburban, 350 tbi. When I dropped in the motor, hooked everything up, went to give it its first start and it just flooded! I started to recheck everything, I found that I had missed a ground near the t-stat housing, there is like two or three grounds in this spot. Being that you say this was a gradual problem, I would clean those grounds up!
Also, yes I see you changed the coolant sensor, but be sure the wires are good, same ground area as well. Unplugging that component makes the ecu think it is -degrees and needs a ton of fuel to fire up. Good luck and keep us posted! ~~Joe