Numba20

iTrader: (1)

As title states, I've got gas blowing out my drivers side header (open headers on car). Pass side is dry. Just got the motor done from a rebuild. Bought new svo 30# injectors. Had Bryan from PCM for less tune car. I am not certain it's not getting spark. Because I tried what I assumed was the fouled plug, and it sparked. I also tried a new(ish) plug to see if the spark was weak. Both fired same. So with the plugged swapped, I started it to find the gas still coming out. I'm not sure if this is just way too much gas in this cylinder, or the plugs weren't firing under compression. I know there is a possibility of a stick injector, but is there anything else? Timing off a tick? Or maybe a computer issue I need to take up with Bryan? Hoping some of the Guru's would help eliminate some possibilities. Thanks all.

Kaleb

shbox

Leaking f/p regulator? Check the vacuum hose.

Numba20

iTrader: (1)

I'll start it tomorrow and double check. but as of now the vac hose is dry. And from what I can see dusty inside? I was monitoring fuel pressure earlier today. 40 with ign on. 40 at idle. 43 on revs. And falls 5 psi or so when I let off. So I'm kinda leaning against FPR. I do have an after market fuel pump though, so that's what keeping that factor within the realm of possibility to me. Hopefully I can get my hands on one of those lights to see if the injector is pulsating correctly. That would rule out electronic issues... So then it's have to be stuck injector right?

FormulaJoe

iTrader: (5)

Pull the fuel rail + injectors but leave the injectors still attached to the rail, then put some paper towel under the injectors and turn the key to the on position, fuel pump should prime and if you have a leaky injector you should see it leak with the system pressurized. If no leak then I'd try pulling the coil wire and with the injectors + rail still over the towel have someone crank the car and look for an injector stuck open. That's what I would do for a quick test. Hope this helps...

Numba20

iTrader: (1)

i wouldve never thought! thank you!

Numba20

iTrader: (1)

where could (should) i go to buy just one bosch EV1 red top injector? can you even buy just one? vendors on here maybe? i did a search online, google shopping, ebay... to no avail.

LilJayV10

iTrader: (39)

Does this sound like a good way to catch your car on fire?

Numba20

iTrader: (1)

Lol at the sig! ^

But nahh, before I got the motor running, I considered taking a match to the car. Lol I figure, whatever happens at this point, happens. I'll let fate decide.

LilJayV10

iTrader: (39)

We have all been there. I know I have several times.

Numba20

iTrader: (1)

what ill do is pull the pigtail connectors to the injectors except 5 and 7, so i can kind of compare. pop the fuel rails up, hold the injectors over a cup and see if it leaks on acc with the pump primed, and then if not, try to crank after unplugging the coil wire of corse. that should reveal whatever problem the injector is having. if its normal, ill assume i just had super bad luck with the NGK TR55's... but im betting the injector acts up because i bought them used from a member on here for cheap. but does anyone know where i can go to pick up just one for pretty cheap?

1994Z28Lt1

iTrader: (1)

Did I miss the part where you swapped the #5 and #7 injectors and the cylinder misfire moved to cylinder five? I would do that before i'd try buying just one injector.

Have you messed with the valvetrain recently? Have you checked compression or done a leakdown test on that cylinder. how do you know its just one cylinder? If its noticeable missing at idle It might only be running on 6 (mixed up plug wires?) I know with my car when I left one wire off i didn't even really notice it was running on 7 until I put some load on it. how are the plug wires routed? touching anything? have any spares to rule out the wire?

Sounds to me like you may be jumping to conclusions unless you have done more troubleshooting than you're telling us about.

Numba20

iTrader: (1)

good detective. lol im on top of all of that though. i just finished (last weekend) an entire top end rebuild. and entire ignition system, along with timing as well. compression reads right at 200 psi in that cyl. i know its only one cly because it doesnt really have a hard miss, of corse, ive never heard the car idle right since purchased, so i wouldnt know if i heard it. but nothing sticks out to me. and no crossed plug wires will cause a hard popping backfire. i had them crossed at one point. thats not the problem. they are all striaght now. wires are brand new as well, MSD 8.5 mm super conductor, and neatly tucked. im ocd so i took the plastic combs that hold them in place and ran them all in order. so none have slack or cross. ive inspected the motor inch by inch trying to get this thing running for the past month. finally happened, and i noticed the gas exiting the header in a bit of a mist. ( i have open headers) so knew 1 or more cylinders were gassing out. so i removed the spark plugs to find a nice dry black carbon build up on cyls 1,3,&5. 7 however was wet and clean. found my culprit. i thought it was a fouled plug at first, but after swapping in a new plug, and the problem persisting, i realized it has to be the injector.

Numba20

iTrader: (1)

Ok, I took formulaJoe's advice and ran the clever test he instructed, and the injector sPrays a lot when the pump primes with ign on only. I left the#5 cyl injector hooked up as well to see what a properly firing one did. It did not spray. I unhooked both electrical harnesses to them and turned the ign on to find nothing happened. Injector did not leak at that point. But when I plugged in the harness to injector 5 & 7, 5 did not do anything and 7 shot out a good amount of fuel making a pshhhhhh sound. So I'm assuming that it's just stuck wide open? Because without the electrical harness plugged into it, it does not leak. Before I buy the new injector tho, I want to make sure that's what it is and not the harness sending the signal to it. I should be able to tell this with a Noid light. I'm just wantin to make sure my hypothesis and experimentation is not flawed to find that it's really something else, someone with more knowledge give a yay or ney?

shbox

Just for curiosity, have you compared the ohms on that injector to others that are working properly? (hope I didn't miss that somewhere in the thread)

Numba20

iTrader: (1)

No but your onto something there. I dont have a means to test it. Lack of the right tools. But I swapped the pigtails, and 5 did it with pigtail 7. It's the current running to it. It is forcing the injector to stay at Max flow. Even with ign on only.

Now my problem. I know what it is... How do I fix it? I don't even know what to look for? Trace the wires? Fuse? A mistake with the new tune? I got no clue on stuff electrical issues confuse the **** outta me.

shbox

It is a pulsing ground from the PCM that makes the injector operate. The +12v sits on it all the time (when key is on). So, it is going to be hard to test the ground side of the circuit to the PCM if you don't have a meter to do it. Maybe the wire to the PCM is chafed and grounding out. Isolate/inspect the wire back to the PCM and see if it still acts the same.

Numba20

iTrader: (1)

There isn't a question I could ask that this guy does now the answer to!

God bless you man!

roninsonic

iTrader: (3)

Easy way to figure it out- swap 5 and 7, and see what happens. If it follows the injector- BOOM, bad injector. If it stays with the connector- The injector ground is shorted somewhere.

Numba20

iTrader: (1)

Cavity what I did. Now time for everyone's favorite! Tracing wires!

roninsonic

iTrader: (3)

You could always be lazy and do what I do- Disconnect the old one, then run a new one

I've done that more times than I'd like to admit... My last beater was a flood car, I replaced at least of a third of the wiring in the damned thing while I had it. I just bought a roll of wire loom at El Vatozone and ran all the new wires through that, through the firewall to the PCM..