Gamefreakgc

First of all, want to say how much of a help this site has been for me. Got a 1991 Toyota pickup (with 3vze V6 engine) two years ago and this site has walked me through every repair so far.

I've been pouring through "tps" forums but can't seem to find an answer to my dillema. I'm currently adjusting my tps and cleaning the throttle body.

I've been getting rough/low idles that won't stay put. One day it's at 600 rpm, the next 400 rpm, then next 800 rpm. My commute is the same every day so I thought it might be the tps. I jumped the two terminals in the diagnostic (TE and E1 or something like that, can't remember now it's been a few days) and the idle did not drop. Something was wrong with my TPS.

I ordered a new one and I'm currently putting it on per the instructions at the 4crawler website. It's been great until I came accross a discrepancy between my FSM and the site. For the 3vze engine, on 4 crawler it says that 1., VTA-E2 should be between 200-800 ohms. The FSM says to be between 470-6100 ohms.

The problem is, my new tps won't fit the 4crawler specs. Either I put it in the 200-800 range and 3. is at almost 4 mm (should be at 0.77mm) or I set 2. and 3. correctly and 1. is at 1300~ ohms. Which one should I follow? I really don't want to put the whole thing back together only to find I did it wrong...

Bottom line is that the new tps will fit the FSM specs, but not 4 crawler specs without one measurement being off.

Here's the link to the 4 crawler:http://www.4crawler.com/4x4/CheapTri....shtml#Dashpot

Link to FSM: http://personal.utulsa.edu/~nathan-b...93throttle.pdf

abecedarian

jumper the check connector and do this:
loosen the TPS (I suggest keeping the screws on the snug side so you can tap on it to move it instead of just grabbing and spinning it) and tap the connector side down until the idle speed drops a bit and the timing mark on the crank are stable. Then, bump the TPS up a little so the marks and idle jump then carefully tap the TPS back down, just to the point the idle changes and the timing marks are stable again. Then snug the TPS down.

And, adjust the idle speed and distributor so idle and ignition are correct, then pull the jumper.

Gamefreakgc

The only problem is that I cannot get to the screws while the engine is running. The TPS faces the firewall and there's too many hoses blocking me from getting a screwdriver in there.

If I had to pick one setting to go off of, should I follow the FSM or the 4crawler site? The author of the article did say that some engine types and years are different (his instructions are for a 22RE, not a 3VZE).

MudHippy

Follow the instructions on FSM pages EG2-241 & EG2-242. Disconnect whatever needs disconnected. Because the engine doesn't need to be running to adjust the TPS. Simple as that.

And just because the idle speed doesn't change when you jump the check connectors doesn't mean that there's a problem with anything, much less the TPS. That's what we have DTCs , and TPS adjustment specs for. Some engines, 3VZ-Es in particular, the idle speed doesn't change when the check connectors are jumped. Mine doesn't. The timing mark isn't affected by it either. I still get DTCs, or no DTCs. But that's all it does on mine.

Gamefreakgc

Thanks for the tips, it works great now! Here's what I did:
I took off the throttle body and set it according to the FSM specs, NOT the 4crawler specs. It's wrong for the 3VZ-E engines on a '91. Maybe #1 will read 200-800 ohms, maybe not. Mine reads 1200 and works great!

Now when the engine is warm it always idles at 800-900 RPM like it should. Doesn't jump to a different RPM each time I stop. Also, a big indicator that something was wrong with the TPS was that when I would idle and turn on the A/C, the RPM woud DROP to 600 instead of kicking up higher since the TPS wasn't in the idle loop like it should have been.

Mine didn't either. I measured the circuits and all was well. Runs great now. Just remember to plug the TPS back in when you are done... forgot to and freaked out when my CEL turned on.

abecedarian

I'm confused about the "can't get a screwdriver in..." thing.

Ever seen one of these:


You're saying that won't fit?

And there's the option of a 1/4 drive ratchet with a bit adapter and a bit to fit the screw....

abecedarian

I cite personal experience on my part as well as many others which contradicts your claim.

You're more than welcome to post your "personal" experience(s) with this.

But I will tell you that, with 100% certainty, the ECU will NOT go in to "limp", "adjust", "baseline" mode... or whatever you want to call it if the IDL-E2 circuit isn't operating properly.


And I find it highly suspect you don't lay claim to a 'yota in your signature, or at least in your avatar.
If you don't own one, why are you here?

MudHippy

I'm citing my experience, as well as many others that fully support my claim. At the moment, the OP is in total agreement with me for one. And if I wanted to round up a list of quotes from other members I could easily do so. And maybe your misread the page I posted above where it states "speed may rise to 1k to 1.3k rpm for 5 seconds". May implies that it's possible that it may not.

But frankly, it doesn't matter to me what you think I should believe about anything. I do enjoy our little game we play though.
True. But at idle speed, the ECU isn't making grand scale changes to the ignition timing. Without the check connectors jumped, it's only supposed to retard by 2°. For whatever reason, that doesn't seem to apply to some of our engines. And no apparent faults exist within our EFI systems that could be causing it.
That's a new one. I'm not even going to dignify that with a response.

abecedarian

Not making any grand scale changes to the timing?
From your post:
"6) Recheck timing. It should be advanced (at least 3' to 18') from initial with SST removed."
18° above initial sounds pretty grand to me: that's nearly triple the initial advance on a 3VZE.

Where you get "retard by 2°" without the jumper is beyond me, and is incorrect according to the page you posted. It says timing should advance 3°-18° without the jumper, completely contrary to your statment and your experience. If you set the base timing to 10° with the jumper, then pull the jumper, the timing should then be fluctuating between 13° and 28°.

Now my personal experience: if I jumper the check connector, the timing on both my RE's is 5° BTDC. If I check timing without the jumper, it fluctuates from 8° to ~20° at idle. Granted, these are RE's, but they behave exactly like the page you posted says. Imagine that....


If the manuals don't agree with the truck, something is wrong... and based on what I've learned here and from experience, I'm willing to bet it isn't the manuals.


Portions of the game are fun, like correcting your errors. People should be given correct information.

But frankly, I find it annoying. You shouldn't need correction.
Seriously....
When posting pages from the manuals how is it possible to get things wrong?