ddub

Alright so my car hasn't been running for about 2 weeks now. I had a problem with a stud on my LIM breaking, long story short I got an easy out stuck and had to replace my LIM, dont bother asking. So I got it and proceeded to reporting my UIM to go a little bigger, ported my TB, TB elbo, and ported my LIM on top and the part that goes to the block. Cleaned everything up and put everything back in the car today. Hooked everything up, made sure fluids were full, checked all plugs and vac lines, plugged any vac lines i wasnt using (checked to make sure there werent any uncapped ones too), etc etc etc. Car was a bit flooded at first start but fired up after a sec. Since it was a little flooded and I have the TB mod done I had to hold the throttle for a little bit till it got a little warmer and idled on its own, not too long. After it was idling on its own I checked everything, no leaks, no pulsing idle, everything seemed perfect amazingly (usually things dont go this well for me). Adjusted idle a tiny bit, not much, everything good. So I turned my car off. Turned it back on started up great no prob. Noticed my e-fan was on the high setting so I turned my car off again, switched the plug to the low setting, go to turn my car back on and it wont fire up. Just cranks REE REE REE REE REE REE REE, over and over. I thought it was flooded or something, so I give it some gas while trying to start, nothing. Figured I'd have to do the egi fuse trick, go to pull it and it was blown...

It was also hot as hell, like in my hand it was too hot to hold? I thought this was really weird. Is there a reason why the EGI Fuse blew? Was this just a coincidence or because I started and turned off my car so many times in a row after sitting for 2 weeks? Or is this a symptom of a short somewhere I should check? Or a plug? I looked around and couldnt see any problems. All plugs where they should be, car was running perfect when it was on, no idea why it happened. Just a coincidence or what?

WAYNE88N/A

If it's hot, you got yourself a short

OK, you got an '88...Good

You're talking the 40A EGI INJ fuse, right?

Disconnect the capacitor from ground (below the trailing coils pack) first off, and tape it up or something to make sure it doesn't contact ground.

The fuse feeds the following: leading ignitor/coil, trailing ignitor/coils, and your 4 injectors...Anything you've "played with" recently?

Get some spare fuses, and also disconnect the secondary plugs from the injectors (I'm trying to get you to remove the "easy" things from the circuit, yet still be able to start the car).

Now, put a good fuse back in, and try to start her...

Fuse blows again- either leading or trailing ignitor/coils are bad, or primary injector(s), or wiring..You could remove the trailing ignitor/coils connectors to further troubleshoot, since you should be able to start the car again...

Fuse doesn't blow- either that capacitor shorted to ground, or your secondaries' circuit is shorted...

ddub

Yes the 40A EGI INJ fuse.

Played with: LIM broke a stud, took TB/Dynamic chamber/UIM out in one piece, disconnected the secondary fuel rail from the UIM so I wouldn't have to take off the fuel lines, secondary injectors were left plugged in with a plastic bag wrapped around them sitting on the engine, so no fuel injectors were unplugged and no fuel lines were undone for primary or secondary. Took LIM out, car sat for 2 weeks. Got new LIM, did some porting, bla bla bla. Put LIM back in bolted it all up. Put UIM/chamber/TB back in maneuvering it around the fuel lines/primary fuel rail. Put the secondary injectors back into the rail/UIM and bolted the rail back to it. Again, no injectors were ever unplugged during this process. Bolted everything back up, torqued to specs. Plugged all connectors I undid back in, put all vac lines in, etc. Started car 3 or 4 seperate times before the fuse blew. Right before the fuse blew, I turned off my car, switched the positive connection for my e-fan from high setting to low setting (where it could have touched the neg ground even though I doubt it), went back in car and car wouldn't start. This is when the fuse had blown. I don't think the connectors touching would cause only the EGI fuse to blow, but thought I'd let you know that.

That's all the info I have, let me know if you have any further questions. Tomorrow when I can get a new fuse and a couple other things I need I'll try what you suggested.

WAYNE88N/A

You don't have your fan circuit on that fuse, do you?

If I had to guess, I'd say that one of the injector backshells got "squished" when you bolted everything back down. I don't know about your car, but on mine there ain't a whole lot of room for those injector plugs to be "free", there always seems to be something right on top of them shoving them down. That's what I would look at first, and then, if you don't see anything obvious, isolate some circuits like I said above...

I don't think you'll be able to troubleshoot with a meter, because those ignition coils might run you straight to ground, making you think you found the short (you could, however, disconnect all the coil plugs, and then be just reading the injector circuits to ground). Unless you pull the small ECU plug to isolate the injectors, make sure your meter uses a 9 volt battery or less, to protect the ECU...

ddub

No I do not, which is why I figured it was just a coincidence it blew right after that. The fan is just hooked to neg battery terminal for ground, and then ignition wire in the engine bay for power.

Backshells? Do you mean the plugs from the harness that connect to the injector or what? I'm not familiar with the term backshell.

ddub

If by backshells you meant the plugs that come off the harness and go into the injector plug, then one of the was resting against the fuel rail, but the outter part is rubber so I don't see how this would be a problem. I moved it out of the way anyway. I'm about to go get some spare fuses to try some things so I'll let you know what happens.


Also, another thing I discovered. The connector on the back of the water pump housing has come off and will NOT go back on. It's really screwed up or something, but it just will not stay on at all. My question is, would it be bad or a problem if I cut the connector off the harness and just ran single prong (dunno the word) connectors (one for each side of the plug) into the plug on the back of the water pump housing instead of using that stock connector? Is that ok?

WAYNE88N/A

I'm sorry, a "backshell" is not something you hear a lot outside of aviation, my bad

The rubber "boot" on the back of the injector connector is what I'm talking about, it should be filled with some form of "potting" compound to keep all pin-to-wire movement to a minimum, but I've never had to dig into one, so I dunno. Anyway, years of being scrunched under fuel rails & such can definitely do damage to the wiring inside of there...

Take a good look at your water thermo switch itself, the back of it can easily crack, which may be why you can't get the plug back on. They're about $45 bucks at the dealer if yours is broke. All kinds of funky things happen when that thermosensor has an "intermittent" open (been there...). If it's the plug itself, do what you can with it for now..

ddub

Well I was trying to take the plug off at one point to replace the coolant line coming off the water pump housing. The connector that goes into the plug on the housing was in the way and i have a very difficult time taking it off, ever since then it wont stay on so I think I screwed up the connector itself. I'll take a look at the plug to make sure its alright, but as long as it is can't I just cut the connector off the harness and run my own prong connectors into the plug there?

WAYNE88N/A

As long as the sensor body and contacts are in good shape, just be sure to keep the two contacts from possibly shorting each other out...

WAYNE88N/A

BTW: you said you had the fan wired into the "ignition wire in the engine bay"...Are you certain you didn't happen to pick a wire that went to the ignitors/coils?

That would explain the fuse blowing a little easier

ddub

That's really possible, actually. The wire you're talking about gets power when you turn the key in the ignition right? The one I tapped into was just a wire I found that got power when the key was turned.

WAYNE88N/A

Yes, the circuit you're blowing the fuse on gets its power from the main relay, which comes online as soon as you turn the key on...The wire you used wouldn't happen to be black with a yellow stripe, would it?

ddub

I'll go check that right now.

ddub

Yep, you are correct, black wire with yellow stripe.

WAYNE88N/A

Dude, how long have you been driving around with your e-fan sucking juice from your ignition & injection circuit, lol?

All right, I think you've solved your fuse blowing problem, hopefully...You need to either add a new fusible power circuit for your fan, or put it on another circuit that doesn't care about sharing a few electrons. I would choose the former, if it was me, those fans suck down some power

ddub

Which circuit is ok to hook it up to then? I want the e-fan to turn on with ignition and that was the only wire I could think of/find.

ddub

If I keep the current ignitor circuit it's on right now but hook it up like in this schematic it should work fine, right?