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Discussion Starter #1 (Edited)
UPDATE: Need Help.... Getting Frustrated

Update: See last post made by me for update.

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Okay, I am having a couple issues here.

One, the engine is out of time. I have checked and double checked the timing (crank, cams, etc). Physically, the timing gear (and reluctor wheel) are good, the timing belt is good, and the cams are good. The timing is not jumping teeth as I keep checking and it's always correct. The sensors (CrAS and CaAS) are within spec of the MKIV TSRM, at least as far as resistance goes. What else is could be causing the timing to go haywire?

The car idles really well, no misfiring that I can tell. It is not pouring fuel out the exhaust and smells like it should. Pulled the plugs (which are new) are a light brown in color.

Second, the engine is having fun with this "rev limit" thing. I have switched ignitors and no change. The TPS seems like it is checking out. It varies it voltage between .5v and 3.7v. The map sensor is seeing the correct voltage as well and does vary itself. Disconnected the OX, Water Temp, Air Temp, and the back CaAS one at a time and the car just will not rev past this "rev limit". The limit will vary depending on how hard I mash the throttle. It seems that if I give the throttle more than 50%, then it will start bouncing. If I mash from idle, 2500.... on the high, I can get the revs up to 4000 but can't go any more as the throttle will be more than 50%. The TPS is within spec as well (adjustment made with feeler gauge).

I have done many searches on the issue and checked some of the common things, ie, coil packs, ignitor, and ECM. I have yet to check the injectors, but I would think that the car could still rev and hit this "rev limit" on all cylinders

This may not be everything that i've tried, but it's all I can remember right now.

I'm at witts end with this thing. It's been over 2yrs since i've driven the car and I just want to drive it again. Plus the wife i'm sure is getting mad that i'm spending more time with the car then her.... but the car came before she did (and I keep reminding her about it too :1poke: ) :angel:

I'm thinking that if I can get the timing corrected, then the rev limit thing may just work itself out.

Sorry for the long post, but i've tried and searched and worked on this for over a month without posting anything, but it seems that i'm getting nowhere. Someone help! :)

Thanks everyone
-J
 

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MK3 Owner For Life
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Have you checked with a timing light ?? Flip back the cover on the ignitor connector and use the green wire for the signal. When my brothers car was one tooth off he had similar problems and could not rev over 4k.

If you need help maybe me and my brohther can stop by sometime to figure it out =D
 

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Discussion Starter #3
I have checked with a timing light.

With TE1 and E1 jumped, it would be at roughly 20 degrees BTDC and jump to 10 every now and then.

Before I adjusted the timing, both the intake and exhaust cams were off by one tooth and I was throwing a code 13. Now when it was like this, the timing read at 10 BTDC, but it would jump and misfire at times on idle. It would also idle kinda rough. Then no matter what I did, could not rev past 2500.

I then adjusted the timing lined the cams up with the markers on the back of the cover. When I did this, then the car idled ver nicely, the code 13 went away, and the timing went to about 20 BTDC. Then I could rev past 2500, but I had to be easy on the throttle.

And I should mention, that the wiring harness is new from Toyota. The previous owner had bought one, so it's new an unmolested. I did not extend the harness at all and routed it a different way.

Zoon, if you're brother wants to stop by and offer some help, I would be game. It would have to be during the week for the next few weeks as I'm going to be out of town for a few weekends in a row.
 

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JZA70 448 rwhp everyday
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you should try putting your ecu in a known working car and see if it does the same thing just to rule that out. If you have checked all sensors associated with timing, ignitor and wiring it would be good to rule out the ECU since its so easy to get at.

~scott
 

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It's been awhile and search is not our friend....

I remember when the swaps first began, that quite a few ppl were having a similar issue (not being able to rev past 2500 and running very rich).

Can it be the map sensor, the tach/guage, or something along those lines? Does anyone know of or remember what I'm talkin' 'bout?

Where are the really old-skewl 1JZers at?

Hey Josh,
If you're game, set sumthin' up for this coming weekend and even if it's only for a couple of hours, I'll come over and turn some wrenches, or help with the IC pipes, etc, etc... make a listof what U got left to do.

E
 

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Discussion Starter #6
yeah, where are all the "ol-skel" 1Jer's out there? ;) Help a brotha out! :)

Anyways, this weekend is no good as I'm going on a family reunion trip and next weekend is no good since I'm probably going to NY for work. I'm trying to fit in some troubleshooting during the week when i can.

any more ideas? keep them coming.
 

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is it possible that timing could be at 180degrees off for such a thing to happen,or check ecu and map on another car also check plug(wires)clipping into map sensor as i've seen them start to back out from the plug and caused almost same symptoms............if you dont have access to another ecu/map pm me as i might be able to help
 

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Does unplugging the TPS change anything? Even if it's within spec, it may still be mis-adjusted.

Same with the MAP sensor.

When it hits this limiter, does the tach needle jump around?
 

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Discussion Starter #9
annoyingrob:
If I unplug the TPS (Throttle Position Sensor), It does not change anything. It will continue to hit the imaginary rev limiter.

If I unplug the MAP, then the car just dies.

When I hit the "limiter" the needle does not jump around very much... it pretty much stays where it is at (it will wiggle *maybe* a couple hundred rpms at the most).


1fastsupra:
I would think that if the timing was off 180 degrees, that the car would refuse to start or run really really bad, but I can't say for sure. Can anyone chime in on this?

I might take you up on your offer to borrow a MAP in the next couple weeks if I can't get Zoon or his brother out to my place to let me try a few sensors :)
 

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Also... You may wanna post out to the MKIIIJZA70 Yahoo group to see if any of those OGs are still on there...

Sorry you're busy now too ;-) Let me know whenever... I owe ya.
 

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Discussion Starter #12 (Edited)
I'll try the TPS and see what that does. ~100 from the dealer isn't too bad to spend. I hope it works though.......

I calibrated that thing three times already. one at .070mm (because I wasn't paying attention), then at .065mm per the MKIV manual, then at .048mm from what I saw on a picture of the 1JZ manual. None would work out and still give me the same results.

On a working car, what would unplugging the TPS generally result as?

E: I've always been busy ;) I'll let you know and we'll get together in a couple weekends. I still need to get you your stuff back.
 

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i have the same timing issue, don't worry about it, it's not related to your rev limiter issue. i have already bought a new tps from toyota, and the same thing with the timing. i am at ~22 degrees with e1 and te1 jumpered, and i've swapped ecu's as well, so i dunno what causes it. i spoke to a local mkiv guy, and he said his is the same, and zazzn's 1jz was the same with his mines ecu.

i remember people haven't that low revlimit before, since search is done, go to www.google.ca and type revlimint 2500 site:supraforums.com, and that'll bring up any hits from this site.
 

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Discussion Starter #16
Satan: Thanks for the offer. I have already ordered a TPS from AutoZone and should be here on Friday. I may not be able to pick it up till Monday though, don't know yet.

annoyingrob: So in other words, everything that is happening to my car right now :)

di_rosa: I appreciate you looking at that issue. I didn't know that could be a common thing among JZ engines. Guess I won't worry too much about it, but being that I have OCD.... it will get figured out one day. As long as it won't affect drivability then that can be dealt with later.

Can anyone else chime in on what their timing is set at, 2J or 1J? I'm quite curious as to how many engines this is common with.
 

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hey,
check the crank sensor or cam ( the one for adjusting the timing) . its probably position over or under one teeth. Not sure. this happened to my shitty 7m and that what i found out was that when i installed it back in it was off by one teeth. the tps might not be the probably. let knwo me knwo what happen. GOOD LUCK:wavey:
 

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you cannot adjust the cam/crank sensors, ignition timing is controlled soley by the ecu.......aside from base timing which is affected by the tps.

code 13 refers to the crank sensor circuit, so if all your wiring checks out, and your ground at the ecu is correctly wire (shared ground between crank and both cam sensors), and your crank sensor checks out resistance wise, i would check the crank sprocket to see if a tooth was damaged.
 

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Discussion Starter #19
donnytran: I have checked the timing over and over again. You cannot install the cams or crank wrong in reference to the timing marks. The crank and cams are marked so that the gears and pullies cannot be installed wrong. (unless something is really broken). I know this because i've looked at it all... over... and over... and over. They just can't be installed wrong.

Now, when putting on the timing belt, the gears can get turned off by a couple teeth causing some problems and causing the sensor to read out of time (and throw code 13).

I have checked and checked the timing and it's dead on. I've checked the sensors and made sure that they are all good and I even checked the wiring (Even though it's a new harness).

That's why I went to get a new TPS. I've eliminated those 4 items already. I will eventually find out about why the timing is off though ;) But right now, I want the car to run well so I can start driving it again...... withdrawls are not fun.

Though a short drive in a MK4 does make things better... for a little bit :)
 

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The drive in the MK4 definitely helps ya keep workin' towards having yours on the road. We're putting those 19s on very soon too.

Let's get yours done, then we can get mine done, then we can focus on the body/paint, and then.... (never ends;-)

Actually,
Isn't there a small plate with teeth on it, just behind the bottom timing belt sprocket/gear? I think I've heard of MKIV guys actually having it welded to the gear/sprocket, because it was loose somehow. That's what the crank-sensor-deal uses for measuring timing, etc... isn't it???

It's supposed to lock on to a key in that bottom timing gear, I believe. It should be right behind the gear, but in front of the seal/timing plate. Contrary to what people might think, it's NOT part of that gear, but a separate piece. Worth looking at....

Sorry, I know it means more work.
 
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