I just replaced a throwout bearing on a '96 Cavi Z24 with a 2.4. The car ran before I had the trans out, but now when I turn the key on there is a clicking from the fuel pump relay. I can hear the pump come on, but the pump doesn't stop running and just fills the cylinders with gas. The car cranks over but hydrolocks. I swapped the relays around, and checked for any shorted wires, but couldn't find anything wrong. Has anyone heard of this happening? I also tried hooking up a scanner, but it wouldn't communicate. Thanks, Jim.
If the engine is hydrolocked it shouldnt turn over, if thats the case just remover your spark plugs and crank the engine. But if it will turnover, not start, and you can smell alot of fuel. Hold the gas pedle to the floor and start the car. This should allow the car to enter "clear flood mode". It turns off the injectors untill the engine starts.
A couple of things. (normal operation) when you turn the key on the pcm tells the fuel pump to turn on for 3-5 seconds then shut off. while you crank, the pcm and ICM read the crank sensor input and turns on the fuel pump again and will continue to run the pump as long as its recieving a pulse from the crank. If you hold the throttle to WOT it will shut off the injectors. The injectors have to get a pulse in order to open, not sure of the pulse side on that one but the PCM will switch either the power or ground in order to shoot gas. If the injector wire is shorted it will just keep blowing fuel in (reguardless of a WOT condition) I had an injector driver go out of a 96 s10 2.2 once which caused the fuel to just dump in to one cylinder.
You said that you couldnt communicate with the pcm, If you didnt have that problem before either, 1 orf two things happened. the pcm is junk or you pinched a wire somewhere.
If you didnt change anything but the throwout bearing you must have a wiring problem that was caused when you pulled or installed the tranny. Maybe you pinched a wire in the bell housing or have a wire off.
01 cav w/01 3400 gam gt 4t45e
^^ The fuel injectors always have 12v to them when the key is on, the PCM switches to ground. So I could see it happening if the right wire was shorted to the frame, tranny, or something else metallic that it would hold the injectors open and fill the cylinders with fuel. So then, even if you put it in flood clear mode, the injector would still be at 100% without the computer telling it to open.
Problems I see with that..... I'd think you'd need to short all 4 ground wires to get all 4 injectors since it's SFI. And if you did, you shouldn't be able to hydrolock it on every cylinder, maybe 1 or 2, but not all of them. The injectors spray into the intake manifold so you should be able to fill the intake with fuel on some of the cylinders if it was all of them, granted you could eventually pull it into the cylinder during cranking but before that happens you'll eventually start getting a puddle of gas behind the car under the tailpipe because you'll push some of the fuel all the way through.
For your scanner, make sure that your cig. lighter fuse isn't blown. If it's blown the DLC will not have power, and a scanner won't work.
How do you come up with the idea that it's hydrolocking?
