EECIV No-Code Output, solid test light.

RonD · Aug 20, 2017

SPOUT is SPark OUT
The TFI system is self contained as far as startup, base timing and RPM timing, but there is no Vacuum Advance timing like older distributors had.

SPOUT comes FROM the computer TO the TFI module, it is in essence, the vacuum advance spark timing needed to match engine load and RPM advance(weights in distributor).
You need to disconnect SPOUT wire to set Base spark timing, 10 or 12degBTDC, drivers choice.
Then reconnect it to get engine to perform correctly for driving

Grenade · Aug 20, 2017

RonD said:
SPOUT is SPark OUT
The TFI system is self contained as far as startup, base timing and RPM timing, but there is no Vacuum Advance timing like older distributors had.

SPOUT comes FROM the computer TO the TFI module, it is in essence, the vacuum advance spark timing needed to match engine load and RPM advance(weights in distributor).
You need to disconnect SPOUT wire to set Base spark timing, 10 or 12degBTDC, drivers choice.
Then reconnect it to get engine to perform correctly for driving

So, am I not correct in assuming that the spout would have at least a partial hand in this engine killing itself once it reaches op temp?

Feck. Well, it's not like there aren't 15 other things that need work, too, so back to the drawing board, I guess.

RonD · Aug 21, 2017

No, no SPOUT jumper with engine warmed up is how you are suppose to set Base Spark timing.
Engine will run with no SPOUT jumper, cold or warm, it will just not perform well with no instant spark advance and retard.
Vacuum advance was instant spark timing change, if driver touched the gas pedal, vacuum changed in intake, instantly.
TFI and computer use the TPS(throttle position sensor) to take the place of Vacuum advance.

Your engine could stall as you slow down with no SPOUT, but should idle fine

Grenade · Aug 21, 2017

Huh, interesting. Now I know!

So, today, I put in new plugs and wires, got a timing light set up, and set the truck to right around 11-12 btdc. Hard to see on that wheel.

Before, when I had the truck having idle issues, it would run steady, albeit fast at idle, and then die. Now, the wee bastard is chugging bad at idle, blowing black smoke, and the tach says it's idling at 1k when it's obviously lower. I KNOW I wired the spark in the right order...but I worry I might have wired them one cylinder off. I TDC'd the motor, saw where the rotor was pointing (towards the back, not towards the side), and set that as #1. Now it has a damn miss, and I can hear the IAC hissing bad, then smoothing out, then hissing bad again with the intake tube off. Or it was. Towards the end, it just started hissing all the time, the engine runs like crap, and shakes from the misses. I'm already planning to yank the plugs and wires again, but is there any mark on the distributor that states where #1 is, and maybe I missed it? I'd like to think the new plugs and wires aren't just crapping out from the word go, but this thing was running and idling great, minus the dying at idle before, and now...it's rolling friggin' coal.

RayInStl · Aug 22, 2017

Go back through the timing process. Something isn't right.

Grenade · Aug 24, 2017

RayInStl said:
Go back through the timing process. Something isn't right.

No kidding. I thought maybe that I'd screwed up the wiring, so I yanked it all off, threw it all back on again, and suddenly, it's idling, it's running...I drove it. My god, I actually drove this piece of monkey crap, albeit just around the cul de sac.

It still has a savage miss somewhere, the engine still stumbles at random at idle (I can hear the intake start hissing, and the engine bogs bad, then comes right back. No input from me.) It revs like a champ, throttle response is perfect... The clutch engagement requires me to put my knee almost up to the roof, but this isn't the forum for that.

I really do want to get this crap 2.9 working, at least until I can find a 4.0 to swap in, so I'm trying to focus on that miss and bog-out. Any thoughts?

The O2 is totally disconnected in this, by the way. The connector was melted in half. Going to crimp the wires back together and weather-seal them with caulk or rtv soon.

RayInStl · Aug 25, 2017

I can't remember if the EECIV requires input from the O2 sensor or not. I think it gets all of it's fuel mixture information from the map sensor, if I remember correctly. But I'd still get that fixed.

You say it revs well and throttle response is good. So I assume you have just a rough idle? Or does the miss continue when holding the revs around 2000 RPM?

If it's just at idle, it could be as simple as a dirty IAC valve. It's that thing bolted to the passenger side of the intake. It's purpose is to allow a metered amount of air past the throttle blades at idle to keep the engine running smooth. If it's dirty, which is very common, the idle quality will suffer. Take it off and clean it with carb cleaner and a plastic bristle brush. Don't use a metal wire brush or you risk damaging the valve. While you're at it, clean the throttle blade and intake of any carbon build up.

Other things to look for are:
* vacuum leaks (especially since you hear a hiss)
* Distributor cap and rotor (may need changed)
* Timing - check the tech section on how to check with a timing light.

Grenade · Aug 26, 2017

I've pulled the IAC prior to this, when it had a different idling issue. Seems to be clean, has function, and does idle fine for a while, minus the miss.

The hiss is from the intake itself, similar to the hiss you hear on a carbed motor when it's about to air-stall, That throaty low strangled hiss. That happens out of nowhere in a clean idle, the engine bogs, and then a blip of the throttle fixes it. Repeat ad nauseum.

Cap and rotor are new, no carbon crapping it up inside. Timing's been set with a light every time I mess with the dizzy to futz with something else. Set dead-nuts at 12 TDC.

If I remember, the O2 is used for fuel trim adjustment on these, or whatever the equivalent was in 1986. No O2 should just have it revert to using MAP and preset tables, so this shouldn't be happening if that were the root cause.

I can set timing, and the rotor spins when I hand crank the engine with no delay or gap, so it's nothing like a worn out chain or belt, best as I can tell. Though, this being supposedly its second motor, god knows if it was done or when.

Grenade · Sep 1, 2017

So, a few days have passed. Truck still starts and idles. Even runs pretty well, though I haven't taken it out on a proper road test yet, due to plates not being legal, etc. Idle issue is still there, but I think I've narrowed it down to possible IAC intermittent failure (like Ray said. I think the IAC itself might have some issue) or the ecm just getting too old and starting its slow decline into obsolescence. TFI is working fine, so it's not that. Coil is spanking the plugs with spark (it's visible and bright in broad daylight), so that's not it. So, unless there's a little green dude bashing away inside my truck, it's gotta be that.

But that's not why I'm adding a post. I have a couple of basic questions. I know, I know... But, this is kind of a derelict truck, so.. cooling system is getting flushed all to hell and back, a lot of the test wiring I've done is going to get routed properly and hidden where it belongs. Now, on top of that, what oil is actually best for an old 2.9, assuming high mileage. The viscosity and such. I was assuming 10-30, but I can't find any marks, and the owner's manual is gone. Second, this thing was running clean and proper before we had 2 days of solid rain, and now I find white steam billowing out of the tailpipe. Did I seriously blow a gasket, or is this more likely condensation? I don't see bubbles coming up through the radiator, and there's no snot in the oil, so...I'm confused. Third, I'm going to be draining, checking, and refilling the diffs in this thing. It's the originial 28 and 7.5, so what kind of oil do I need? I assumed 80weight, but I also know assuming wrecks stuff.

Anyway, there we go. Heap abuse upon my head for this.

Grenade · Sep 28, 2017

Just for future reference, in case any new folk run into the same problems I had, the white smoke really was just condensation. I guess some of the seals aren't the greatest on a 30 year old tank, and a little bit of water can get into the gas and make it look like a head gasket failed.

The idle quality is way better now that I've got the Spout hooked back up. Still can't find an OEM connector pill for that thing, but I've got it jumpered with just wire at the moment. Engine revs nicely, even with the "2.9 tick". Still can't seem to get the codes to flash, though. Still has a little engine shake at idle, too, but I'm not even sure what could cause that anymore. It runs steady, fires up first time, every time, and I'm guessing it's just one of those things an old engine will do. Hopefully, it survives until I can get the light issue sorted out.

RayInStl · Sep 29, 2017

If you have a rough idle that goes away when you give it some gas, clean and inspect your IAC (Idle Air Control) valve. It's on the passenger side of the intake. It's purpose is to let a small amount of air past the throttle blades at idle to keep the engine from choking out. It's essentially a controlled vacuum leak. They get carbon buildup that restricts the flow of air. Also check the throttle to see if it needs to be cleaned.

If either needs cleaning, I suggest using a nylon bristle brush and carb or intake cleaner. Gas will work in a pinch. Don't use anything too strong like degreasers.

If that's not it, I'd suspect a mild vacuum leak somewhere.

Glad to hear it's running better!

EECIV No-Code Output, solid test light.

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