MT_turbotoy

Hello, im new to this forum but not new to Yota forums
Rig: 87 P/U 22rte

Im having a problem getting the truck to advance the timing, i set the timing to 5 BTDC with the jumpers but for the life of me cant get the timing to advance at all....im running 10psi on 89 octane fuel but even when i just push 4psi it still wont advance, every now and then i will pull a code 6 (rpm signal) but i cant figure out what it is. replaced the distributor, checked the air gap it was all good re-timed the truck but still it won't advance but the code went away, any ideas i need to get this bug solved
thanks in advance.

MT_turbotoy

bump bump

myyota

I don`t know anything about turbo trucks, but i know that the timming advance is controled by the computer, have you tryed a diferent computer to see if that solves the problem ?.

MT_turbotoy

the timing should be all the same wether turbo or N/A i have tried three different ECU's all with the same results

abecedarian

How do you know it's not advancing? Are you checking the timing with a jumper in the test plug so the ecu will allow you to set the base timing?

If the knock sensor picks up what the ecu might interpret as detonation the ecu drops the timing straight to the base setting.
Also, if there's something wrong with the TPS, in particular the IDL-E2 contacts do not open when the throttle does, the ignition may not advance properly as well.

sb5walker

To check for timing advance, of course you need to not have the jumper set - I'm sure you already know; just thought it was worth mentioning.

If timing is not advancing, the ecu is probably not receiving crankshaft position signals from the signal generating coil in the distrib, so it was good to check the air gap. That might be the source of your rpm code, too - IDK about the rte. When you checked the air gap, did you also check the signal coil resistance per factory spec? Also, make sure the contacts are good between the distrib & igniter, and between the igniter and ecu. Check that no pins are pushed back in the connectors, and clean up the igniter ground.

MT_turbotoy

i know its not advance by watching it with a timing light, and not with it jumped. i've already ruled out the TPS by just re seting it just to make sure that it not that.
im gonna ohm the coil resistance and check the ignitor, because i got another code 6
thanks everyone for there input

sb5walker

Signal pickup coil, in the distributor, right?

The fsm specs for a 93 RE are on page IG-8; not sure of the specs for your truck:
http://www.ncttora.com/fsm/1993/ignition/4onvehicl.pdf

If the coil is bad, I see that Rockauto has a Beck/Arnley for $37 - I've had good luck with Beck/Arnley parts - often they are from Japanese manufacturers, though not always:
http://www.rockauto.com/catalog/x,ca...,parttype,7176

MT_turbotoy

Problem solved, it was a faulty igniter assembly. lucky i had one in all my extra yota stuff.
truck now sucessfully advances the timing. thanks everyone for your help.

abecedarian

Cool beans.

I was getting ready to have to ask sb5walker about which generating signal in the distributor to check- the 22rte only has 1 hall-effect generator which has a single reluctor with 90 degree spacing so crank position is as accurate as that allows, and why reference a 93 FSM when the 22rte was left behind 5 years prior... but it's water under the bridge now.

sb5walker

Congrats on getting that fixed, MT_turbotoy

Abe, now you've got me confused - all the 22re/rte/rec/rtec distribs only have one pickup coil... don't they? As far as referencing the 93 fsm, yes, not useful from a spec point of view - true; I just wanted to make sure folks knew I was talking about the pickup coil in the distrib as opposed to the ignition coil, and I knew the 93 manual has pics and an explanation of the signal rotor/pickup coil. I think I mentioned the specs in there were for a different engine and that I don't know the pickup coil resistance spec for the 87 22rte. I don't know of a manual for that online. Is there one?

abecedarian

Personally, I haven't seen a manual for the RTE engines.

But my implications about the pick-up coil were inspired by this bit of text you posted: Obviously a 4 point reluctor can't generate anything with much precision much less relay crankshaft position with any degree of accuracy. In this respect, the distributor in any 22re/rte (and some r's) is little more than glorified points and can only say that a plug is about to fire. We could go into the ECU design to try and explain how the ECU can calculate crank position based on getting 2 pulses for each crank revolution (how can the ecu figure 10 degrees when the pulses come every 180 degrees?) but that'd be a waste of time... just like this post.

sb5walker

Interesting info, Abe - thanks. You gave me motivation to try and understand better just how the 22re series handles timing. As you suggested, I see that the ecu reads the Ne signal from the distributor (passed through the igniter) mainly to determine the initial timing. Then once the engine exceeds a "certain rpm", the ecu begins sending IGT ignition timing signals to the igniter, and advance is based on a number of different inputs including engine load (Vs - the primary signal from the vafm, indicating vane position) engine rpm, engine temp, and knock sensor signals.

Before the igniter starts receiving IGT (as when cranking, for example), it uses the Ne signal from the signal coil in the distributor to time spark, and in fact if the IGT signal from the ecu fails to make it to the igniter for some reason (including the possibility of the IGT circuit within the igniter having failed), the igniter can continue to fire spark based only on Ne, which means there is no advance. This must have been what was going on with your truck, MT_turbotoy.

Here's a great tech article on OBD I ignition that includes info on the 22re series ignition system (called "VAST" - variable advance spark timing):
http://www.autoshop101.com/forms/h23.pdf

The VAST system operation is explained on pages 6 and 8, and there is actually troubleshooting info for the no spark advance condition on page 14. Sorry I didn't check that out sooner, MT_turbotoy, probably would have saved you some time.

The 3vze uses a different system, "ESA" (electronic spark advance), in which there are camshaft positions signals (G1 and G2) in addition to Ne, and those inputs connect directly to the ecu instead of the igniter. And the Ne reluctor has many more teeth, as Abe pointed out. Otherwise, the ecu calculates spark advance based on pretty much the same inputs as on the 22re. I guess that means the 3vze won't run at all if the igniter doesn't receive IGT. ESA info on pages 5 and 7 (and the top of 8) in the above link.

Not sure if anyone will be interested in all that rot - a geek like me gets off on that stuff - YMMV