WishIwasayotaGOD

So 1993 Toyota 4runner is having major power loss and runs extremely rough I ran a diagnostics on it and no codes came up the only thing that jumped out to me is when I did the data stream the advance spark timing was jumping all over the place. Could this cause an issue or may it be something else

toiyodah4WD

Are you saying when you checked timing the mark was all over the place? I'd say that anyway suggests a new distributor will help your 4runner

WishIwasayotaGOD

i was running a data stream with a code reader and the spark advance which is controlled by vacuum is everywhere when at idle it stayed steady but when I brang the rpms up it would jump from positive or negative. I have replaced the distributor wires bit still having same problem I have also timed it but not with a light. I have a miss on three cylinders but no gas coming out of the tail pipe so I am not sure what is going on

millball

It is certain that the ignition timing advance on a 1993 3vz-e engine is NOT controlled by engine vacuum.

What device are you using to access the data stream on pre-OBD2 Toyota?? Just curious.

ep-jb

Apologies in advance if I'm in the wrong place (old guy Knew-Bee error?)
It seems as though it's recommended to post similar questions on an existing thread, so here goes -

I recently bought a 'new' 93 4Runner (194,000mi - V6) and it naturally has a few issues;
Most frustrating is that my Check Engine Light comes on at approx 15 mph, but then cancels out at ignition off. I haven't been able to jump the OBD to check codes as nothing shows up after I've shut it down to jump the pins. The local parts stores all say that their scanners won't work pre '95. I don't have $ to buy a scanner just to find out it won't tell me anything either.

My Blue Baby gets about 14mpg ave, runs a bit rich, and hard starts (floods?) if I make the mistake of releasing the key a moment before it starts.

I've searched with a variety of keywords/phrases, and haven't found what I need .... Any thoughts (other than 'who is this, and why is he asking these simple questions?') ??

Thanks in advance for your time, advice, and my new Yota home.

dropzone

iTrader: (6)

ready codes on a 2nd gen 4Runner

Charchee

Follow the instructions mentioned in the video posted above and let us know what you come up with. There are lot's of things that will throw off the fuel to air ratio so find that code and we'll try and work from there.

ep-jb

I didn't even have a chance to get back from the parts store (she slow leaks PS fluid) before you reached out to help me ... thanks for taking time out of your day.

I had tried jumping the pins before I posted, but the video you shared was as straight fwd as any I had found.
Just in case, I took my laptop out (eyes aren't quite what they used to be) and step-by-stepped it again - Still nothing.

The problem with my code retrieval seems to be that it doesn't exist unless I'm over 15-17mph, and it clears if I take ignition switch from 'on' to 'acc'. Once I've shut it down, even just to the 'acc' position - the code clears (at least from triggering the check engine light). It won't come back on until it's running and at trigger speed (not Roy Rogers horse).

I was an Aircraft Elec in a previous life, and part of me thinks 'I wonder if I can keep the jumper in while I drive and see the code that way?' - but a more cautious, and prevailing side says 'do you really have the $$ to replace something you broke because you wondered if it would work?'. As the former AC Elec, I'm uncomfortable with ghosts - troubleshooting on the ground could turn into a 'swap it out and let's see if that fixed it' ordeal due to inability to recreate at altitude, under G's conditions.

I used to get my hands dirty when things were carbureted, points, etc., and I'm not afraid to use the techno resources available today - but everything integrated makes life tougher on us old guys

Thanks again for the quick response and offer of help - I'll post back to this thread if/when I have something new.
p.s. - I would have left you a thanks, but I couldn't find a way to do it

jb from El Paso

ep-jb

My apologies DropZone - I didn't mean to leave you out of the 'Thanks'.
My assumption (we all know what is said about that) was, that Charchee had dug up your vid and posted it for my viewing pleasure.
Thanks to you for making me feel at home

jb

Charchee

That code should be stored in there. What did you see when you did your test? A steady blink or nothing?

ep-jb

Nothing Charchee

Charchee

If I remember right, when you have no codes to report and you have the jumper in place, you should see a steady blink of the CEL, one per second. I believe that is the signal that the CEL is working and there are no codes. Check your jumper to make sure it is in the right place.

ep-jb

3rd time's the charm ... Same Jumper, Same pins - got results code 52 - Knock sensor (KS) -circuitWiring, KS, ECM
Sounds like it's not a fun job from the yotatech post I found
https://www.yotatech.com/forums/f116...e-read-291009/
Pull the intake manifold to get to the sensor, pigtail, check wiring .... arghh

Also found a McGyver sp? post on the same issue
https://www.yotatech.com/forums/f116...e-52-a-254275/
Seems like a fair amount of work for a 'quick fix'

And one last one that talks about the same the other 2 do.
If I take the code and info I've read at face value - seems like it's probably a bad wire that would be almost the same job as replacing total with the additional cost of a knockoff sensor ($25).

I haven't heard any knock, and I'm going to keep the fingers crossed while I throw change in a can and keep reading to prepare for the new adventure (barring new information, or a worsening problem).

Thanks for being persistent with me, as I had reached 'head scratching' stage after the second no go on the CEL test

I'll keep you posted down the road unless you have a magic wand you're willing to rent

jb from EP

toiyodah4WD

Remembering from a recent post re code 52: Scope explained since the Knock wiring and/or sensor has failed, the ECU is no longer getting a signal, so ECU retards timing hedging bets against any possible knocking of pistons, preventing catastrophic damage. So, probably no knocking has occurred (or will occurr). But, your truck will drive like cr*p until you replace sensor and/or pigtail wire. The CW is replace both (or if only one pigtail wire) since you are there, and you should use Toyota OE replacement. How many miles on this? Do you know if HGasket replaced?

Charchee

That's right. It won't knock because the ecm is missing the information. Kind of like how you can walk with your eyes closed but you probably wouldn't run without being able to see. Definitely do the sensor and pigtail. Before you go in, look for valve cover leaks, bad coolant lines or vacuum lines or anything else you are actually going to be able to put you hands on without the top end of the engine off. It's a great time to address any issues. Change your PCV valve. It's a bear to get to any other time. Buy quality gaskets for your reassembly. Cheap ones will send you right back in there to fix air leaks. If you love the old truck, you're going to be back in there at some point anyway so think of it as a great learning experience. The first time I did it, I was very intimidated. Ever since, I'm not scared at all to tear it down to the heads.

ep-jb

Just bought it a month ago - fell on some hard times supporting my Wounded Warrior son's household as well as my own, so I bought it at a buy here-pay here to replace my repo'd Camry.

Don't know much other than the CEL was on when I bought it, and it's grandfathered in EP so no need for a fix before sale/registration/license.
Sounded pretty solid for a 23 yr old truck with 194k, so I bought it. Don't think I'll be disappointed in the long run - it's been a good month, seems tight.
This would explain the running rich, the hard start (flood), the less than expected mpg, and the rather sluggish performance. I'm not to concerned about any of that - I know I'm heavy on the emissions, and operating costs are higher than they could be, but it doesn't seem to be critical and can wait till I get caught up in a couple months now that I'm back in EP with my son and only running one household.

I'll save for the OEM, and already considered pulling heads while I was in that deep. Thanks for asking, I would guess it's never been changed although I don't see any real sign of leakage or crossover. Might as well as long as I'm there - Timing chain/belt will most likely be a part of that 'vacation time' also.

As a positive, everything points to a wire, and I've replaced more than a few of those - and I've found a site that (if your responses are any indication) really cares.

Thanks again - it will be a while before I get to this project, but you can be sure I will use yotatech as a resource.

If I don't hear from you before then, I hope you have an inspirational Christmas, and a New Year that is full of Grace

Truly
jb from ep

ep-jb

Great stuff Charchee - Thanks again

Charchee

Don't pull the heads unless you know you have to. I wasn't suggesting that at all. You are going to be beneath all of the intake but above the heads. I was just talking about intake gaskets and maybe valve cover gaskets if yours are leaking. Best of luck with it. Get in touch with me if you need any help. I've got a bunch of spare parts for a truck like that. Check with me if you need anything.

millball

Would'nt hurt to check the valve lash.

ep-jb

Thank you for your amazing support Charchee - I'll keep you posted