sixOHfour

1990 Pickup 4x4 3vze 5spd. The RPM's will only drop when it is jumped while cold. When it is hot it does nothing. So is it possible to set the timing while its cold or will I screw it up even worse than it is?

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drmix

You should do it when its warm. It probably does drop but its hard to tell since its not a significant drop in rpms.

One thing I check to make sure that its jumped is my cel starts flashing not sure if its suppose to or not but it works lol.

DeathCougar

You set initial timing with it cold (without the engine running) and you set ignition timing with it running, warm, at idle.

Since the engine is at high idle when cold, you can't set accurate timing.

sb5walker

Make sure the TPS is grounding IDL to E2 (continuity) when throttle plate is closed (idle position). That's required to set timing. The position of the sensor on the throttle body changed at one point, and the connector changed later, so it's hard to say whether IDL and E2 are the upper or lower two terminals. On my 89 the connector faces the left side of the vehicle, and they're the lower two. On late model trucks the connector faces inward and they're the upper two.
http://www.toyotanation.com/forum/sh...44#post3111544
1993 (late model style) fsm: http://personal.utulsa.edu/~nathan-b...93throttle.pdf

Make sure idle speed is 800 rpm +-50 when motor is hot. Adjust by turning large, front-facing flat-head scew near top of throttle body.

To be honest I don't detect an rpm drop on my veezy either, never have. So if you've verified that the jumper is set correctly, and that IDL is grounding to E2, and idle speed is 800 +-50, my advice would be to just set the timing and not worry about it. Definitely do allow it to warm up first, tho.

http://personal.utulsa.edu/~nathan-b...e/64tuneup.pdf (pg EG2-25)

MudHippy

Like that makes any sense...

The only "timing" you set without the engine running is the cam timing. To which the term "initial" is not applicable.

"Initial" timing refers to "initial" ignition timing. And "initial" ignition timing, is just another way of saying "base" ignition timing. Which is exactly what you're setting when you set the ignition timing. Mine's the same way, for whatever reason. Check connectors jumped = no change in rpm or ignition timing angle. So I don't even bother anymore. But the point of the procedure isn't to change the rpms actually. And any change in rpms is supposed to be temporary. You're not to even start the initial timing adjustment step until the rpms "stabilize" after jumping the check connectors. The supposed point of which being to disable/default the ESA(Electronic Spark Advance) system while setting the initial timing. Otherwise it could be trying to self-adjust itself, and that would make correctly setting the initial timing more difficult(or impossible). Supposedly...though it doesn't appear work that way on my engine. LIke I said, it makes no difference whether I jump the check connectors or not. And no, there's no logical explaination for it(such as the TPS being out of adjustment).



So is it possible to set ignition timing while cold? Yes it is. Well, it is for me atleast. If I'm trying to set it to stock specs that is. I don't even need to have the engine running when I do neither.

How? Easy! Just turn the distributor fully counter-clockwise until it stops then tighten the bolt holding the distributor in place. There ya be! Set dead-on 10° BTDC just like the book recommends. Couldn't be any simpler. Fully goof proof. That's on my 88 3VZE anyways. Isn't that the case for all 3VZEs though? Or is the, or maybe just my, 88 special in that respect? I'd like to believe Toyota did that on purpose...sure makes life easier anyways.

DeathCougar

Potato, Pototo. I call it initial timing because I am setting the timing before I start the engine. Cam timing is a more accurate "technical term"

And you telling him the incorrect way to set timing is pretty interesting. If the engine does not change RPM's, YOU HAVE A PROBLEM. Even if the truck is "running right" by your ears, that doesn't mean its running correctly. While at high idle (cold) the ignition timing is different than at idle. Don't set timing while cold with an electronic ignition, it will be wrong. And that is a FACT.

MudHippy

Sorry post editted too late...I believe it contains the info you're interested in now.

Just in case there's any confusion. Initial ignition timing is a mechanical adjustment that in reality has NOTHING AT ALL to do with whether the engine is "hot", "cold", running or not. What you're really doing when you "set" it is "finding" it. It's always there in the exact same spot, in terms of where the distributor is "clocked".

But yes, technically, you are correct. And so am I.

Don't ya hate that?

sixOHfour

Ok guys, this is confusing the crap out of me. Rotating my distributor fully CCW will reset it to STOCK settings????

My TPS is adjusted correctly according to the multimeter, but it runs a hell of a lot better with it unplugged. Would I be able to set the timing with the TPS unplugged?

xxxtreme22r

Doing it the way the FSM tells you is the only right way to do it, if something is preventing you from doing so then that issue must be taken care of. Can't get any simpler answer then that. If this was a carb'd 22r yes you can set ignition timing while cold as long as your off the high idle cam on the carb and/or engine RPM is below 900 RPM. Which it shouldn't be if your on the high idle cam.

I am not 100 % sure if the EFI 22re has a mechanical advance in the dizzy or not. IIRC it does not but I could be wrong. But with what I said above it doesn't really matter anyway.

xxxtreme22r

another thing you can do, put your timing light on the truck without the jumper in read timing, put jumper in and reread timing what is the difference in the timing numbers. Ignore the RPM change or lack thereof. Also your CEL should come on and flash if the jumper is installed properly. If your CEL is on before installing jumper read it and fix it first.

Team420

exactly!! Dont just go turn ur dizzy fully ccw and expect it to be set correctly.... warm the engine to normal operating temp, jump the diag terminals, connect ye olde timing light, and do it correctly!

xxxtreme22r

IIRC and this is only on my 22r it may or may not be different on the 22re I do not know for sure, but 0 degrees should be right dead center of the adjustment "window". If it's not then the dizzy is a tooth or two off and needs to be fixed. Hopefully someone can confirm but last time I did the timing on 92 Toy's engine 0 degrees was dead center of his as well. IIRC.

sb5walker

No, as mentioned the computer needs both the jumper set and tps grounding idl to e2 in in order to set base timing. At least if you want to do it per the fsm, which has always worked for me.

If the motor runs better with tps unattached then there are some other engine control issues that will need to be run down, but that's aside from setting the timing. For tracking those down, I'd recommend using the voltage specs for the terminals on the ecu, listed in the MFI System - Troubleshooting chapter. That shows directly what the ecu is seeing, and will show wiring faults, not just sensor resistance data. But I would do that after setting the timing; at least get it in the ballpark the best you can. You can set it again after tracking down your engine control issue.

DeathCougar

The TPS is there for a reason. You can't simply unplug it and expect to be able to drive around just fine. Resolve that issue, then move on to the timing issue.

MudHippy

I'm 99.99% sure that it will. I'm basing that on the fact that the ignition system, namely the distributor, is the same on my 88 as it is on your 90. If the initial ingition timing isn't able to be set in the exact same manner as mine I will be VERY suprised.

This should not discourage you from following the FSM instructions on how to set the initial ignition timing. That's the ONLY way you can be sure what I'm speculating is true or not. Since you've obviously never set/found it before.

If it is true, then I reiterate, YES you CAN set it cold. You can set it without jumping the check connectors. You can set it without a timing light. You can set it without the engine running. Hell, you can set it blindfolded with one hand tied behind your back. BECAUSE YOU CAN'T MISS IT!!!