CrustyYota

Hi, could use some help. Working on '93 4x4 truck sat many years. It's the 22re. Changed tank and fuel pump. Starts up runs about two minutes then dies. I know it's flooding. Also know it's the injectors. Dunno y the injectors are operating with key just to on position with engine off??? I assume they are randomly operating when it is running as well. Any ideas? All grounds cleaned, all injectors removed & cleaned reinstalled. Po rewired fuel pump to run when key on. Good psi 50+.

osv

post up the symptoms you are seeing, for example, how do you know that it's flooding.

is it throwing any codes?

CrustyYota

no codes cel flashing fast with jumper wire in diag box. I can hear and feel injectors clicking and spraying fuel cyls fill up with gas in minutes. Not the csi. It's the primary injectors. Love the yotatech forum, been reading for a week. Someone knows what this problem is. Thx

osv

if the cylinders were really filling up with gas it would hydrolock the engine :-0

ignition is on, but the engine is not running when that's happening??

CrustyYota

Right, engine off key to on. They are clicking and spraying fuel. However, when I unplug ecu the injectors don't click. Does that mean the ecu is fried? It will and has filled cylinders before . Trying not to let it fire up anymore cause afraid of hydro lock. I want the injectors to stop that lol. Thx OSV holler back if u get a chance I'm new here first forum ever joined.

CrustyYota

Also, I opened the ecu think I see burnt spot. But I'd like confirmation that it's gotta be the ecu before I order one. I've checked injector plugs they aren't shorting to ground with key off so I don't think wire harness shorted looks pretty good shape.

Flash319

Ecu does not directly generate injection pulses. They come from the pickup in the distributor and the ecu then uses that signal to change the duration and timing of the injector pulses. if the truck runs there is nothing wrong with the ecu.

CrustyYota

yes but with pickup coil wire unplugged the injectors are still operating engine off key on.

Flash319

How do you know this?

CrustyYota

i can hear and feel them clicking and hear the fuel spraying when they open . The cylinders fill up with key on. Thx flash

Flash319

You gotta take a video with sound of this. Very strange.

CrustyYota

i agree it's very strange, idk how to do a video yet. Was hoping someone had same problem before. Truck fires right up after I turn by hand plugs out and clear the flooded cylinders...but runs way rich and I'm afraid to hydrolock it. So I'm tryin make the injectors stop doin that.

osv

well, we know that the fuel pump isn't supposed to turn on until there is air moving thru the flap in the afm: http://www.4crawler.com/4x4/CheapTri...ORelayLocation

the volume of fuel that you are talking about in the cylinders makes me wonder if the fuel pump is running when the ignition key is turned on... the only other way that there could be fuel coming out of the injectors is if it's bleeding off residual pressure, but how much volume could that be?

checking the circuit open relay isn't really related to the injector problem, but this is such a weird situation, i'm wondering if someone hacked some wiring or whatever.

CrustyYota

yes and thx for all responses. The fuel pump was wired hot to ign on years ago. This was farm truck forever in family since '03 or earlier. Sat for years till fuel pump got froze up...then I got it. Any fresh ideas is a help. I know it ran for years with rewired pump. What I can't figure out is why injectors are operating at random with key just on. Thx again everyone.

osv

i'm not sure that the coil wire is going to have any effect on the pulses that the ecu sees, since the coil wire is part of the high-voltage circuitry for firing the spark plugs?

with modern fuel injection, the base timing gets set, it doesn't change, the pulses coming out of the distributor should be from a hall effect sensor(aka magnet) to the ecu, which then alters the timing as necessary, and sends the pulses back to the high-voltage part of the ignition system.

our primitive 22re fuel injection does have it's own ignition setup, however, need to look at the signal path... i'm just saying that we can't yet rule out the possibility that timing pulses are getting to the ecu regardless of what happens with the coil wire.

our efi stuff is batch-fired, it's not sequential at all, the injector timing is never right, because with batch-fired systems the injector can be squirting onto the back of a closed valve, as i understand it.

osv

if you put it back to factory, it won't be turning on the fuel pump, which should help the hydrolock situation, and put less gas into the engine oil.

or maybe unhook the power to the fuel pump while you are troubleshooting this.

TC22RE

As a thought, you mentioned 50+ psi of fuel pressure, I'm fairly sure the stock fuel pressure should be around 43 psi, 38-44psi with +B and FP jumped and the engine off, 33-37psi with the engine running at idle and vacuum to the regulator.. It's possible you have too much fuel pressure leading to flooding.

CrustyYota

gonna cut power to fuel pump today and see if injectors still click, guess that will eliminate fuel pressure too high idea. dunno y it would get signal to inject without even turning it over. Thx guys.

CrustyYota

Ok, I cut power to fuel pump and yep injectors still clicking randomly with key on.

TC22RE

Hmm, I must have glazed over the part about the clicking randomly, forgive me. I think injector pulse will happen regardless of an operational fuel pump or not. But having them just sort of go off on their own is something else entirely. Could be something funky like the injector drivers having gone out. Or the signal to the driver corrupted from interference (spark plug wires?) / faulty distributor. Do you have access to noid lights (to plug into the injector harness), if you have 4 of them you can visibly see which injectors are firing and which aren't and when. The injector driver, if I recall correctly, fires in batches, meaning 2 injectors fire at the same time, then the other 2. While watching you can probably see if it's just 2 injectors randomly going off, or all 4. If it was just 2 I would lean towards a bad injector driver, if its all of them I would think the signal to the driver from the distributor is bad.