Timing/TPS/Low Idle Issue 1993 Land Cruiser

[willyd1]

80 Series Tech, I need some assistance. I recently replaced my distributor and TPS, and I'm experiencing the following:

1. Low idle. Idling at around 400-500RPM

2. When setting the timing, I let the car warm up and then jump the TE1 and E1 terminals, and oddly enough the timing DOES NOT change from what it was at beforeI went into diagnostic mode. I'm currently sitting at 7 BTDC and the car runs okay, but only after warming up. When I first start up, I'll hit the gas and the engine power goes in and out for a little bit and then eventually evens out and I can take off. I tried setting it at 3 BTDC with the terminals connected but the engine runs pretty rough

3. When setting the timing, the timing light is not flashing consistently. I was thinking it would flash at an even rate, but it's noticeably not even which I don't know if that is wrong or not. The other thing is that every few flashes, the mark is not there. As in the yellow TDC mark on the crankshaft pulley is not there every few flashes. Which I find concerning

4. Low Battery power. Not sure this is related at all, but the battery meter on the dash shows around 10V when it should show 14 to my understanding. Took it to Autozone to make sure the new battery they gave me (and the alternator I recently installed) weren't busted, but they said all is good. When I hit the gas, the voltage goes up to 14/15V, and the headlights get stronger. Not sure if this can have anything to do with my timing or anything

I need to go through the procedure to set the TPS in the right position, but I've moved it into different positions to just feel it out and it doesn't change RPM's or timing. Also if you have any tips on how to set the TPS without having to apply vacuum, that procedure seems out of my league and so if there's a way to do it with just a multimeter, I'm all ears. Sorry, I know that's a lot of info but I would appreciate any help on this because I'm stumped!

 

[sysmod]

hey there, im curious if this messes with your turning at idle at all? any squealing from your ps belt?

 

[Malleus]

@willyd1
First, did you replace the distributor and TPS with Toyota OEM parts, or aftermarket?

Second, here's the ignition timing setting procedure, from the 1993 service manual:
1). check for spark;
2). check the resistance of the high tension cords;
3). check spark plugs for wear/corrosion/gap;
4). inspect primary/secondary coil;
5). inspect distributor air gaps/signal generator resistances;
6). verify distributor installation (with engine valve train timing); and only then
7). check ignition timing with timing light, DLC connector TE1 and E1 terminals connected at 3° BTDC at idle (650 rpm ± 50rpm), w/ transmission in neutral and A/C off.
Then, further check ignition timing with timing light, DLC connector TE1 and E1 terminals not connected, at between 2° BTDC and 13° BTDC at idle, w/ transmission in neutral and A/C off.

If, after performing these steps, the ignition timing is still off, you have to check the values of the ECM terminals, which are also listed in the manual.

All this can be found on pages IG-1 through IG-64, of the 1993 service manual. Unlike a small block Chevy, you cannot skip steps working on the 1FZ-FE, because so much of the engine operation is controlled by the preprogrammed ECM.

Lastly, for the TPS:

If the TPS is OK, you have to check the ECM terminals of the TPS, this is on page EG-238 through EG-239.

 

[Malleus]

hey there, im curious if this messes with your turning at idle at all? any squealing from your ps belt?

There's no power steering belt on a 1993 80 series 1FZ-FE engine. The power steering pump is gear driven off the timing gear.

 

[sysmod]

There's no power steering belt on a 1993 80 series 1FZ-FE engine. The power steering pump is gear driven off the timing gear.

woops! I saw 93 and thought 3FE

 

[Malleus]

NP

 

[Cruisersncans]

hey there, im curious if this messes with your turning at idle at all? any squealing from your ps belt?

I know there is no PS belt because of the other answer but what were you leading towards? I’m having similar issues as op and I do have a slight intermittent squeak/squeal from one of the belts.

 

[sysmod]

I know there is no PS belt because of the other answer but what were you leading towards? I’m having similar issues as op and I do have a slight intermittent squeak/squeal from one of the belts.wasthought there may be an issue with the alternator

If it was a 3fe, I was thinking there may be an issue with the ps belt or alternator. On the 3fe there are two pulleys on the alternator: for the power steering belt and water pump belt; my PS belt was loose and sitting too deep in the alterantor pulley which had resulted in low rpms, low voltage, squeeling ps at low speeds for me--a tightened oem belt + new alternator solved many of my issues.