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Hi ok so i have a 93 4runner with the 3vze. I bought it a couple weeks ago and it has been running great. Its an Automatic.

All of a sudden after driving the car for about 5 minutes one morning, it will not pass 2000rpm. When it hits 2000rpm it acts and feels as if it has a rev limiter and drops down to around 1500rpm. It does this over and over again as long as I press the gas to get it up to 2000rpm. This is the THIRD time it has happened. The first TWO times it happened it got better over night and I thought it was a clog in the fuel system. Since then I have replaced the fuel filter and ran iso-HEET through my gas, and it STILL does it after the engine warms up. It seems that as soon as the engine warms up it starts to have the problem because for the first 5 mins of driving it drives fine.

The truck was sitting for 2 years prior to me owning it, so my guess was that the gas was bad and maybe the fuel pressure regulator or fuel pump???? The previous owner had head gasket, timing belt, water pump, etc all done in the 2 years it was garage kept. Like i said it was driving perfect for 2 weeks, only now the problem is occurring. I CHECKED for codes with a hotwire and all I got were steady blinks so I am assuming that means there are no codes. The next thing I was gonna check was air intake and throttle body, but I don't think it is that because it feels like there is a REV limiter. it surges at the exact same time every time!!!! please help!!!! Also the "rear anti lock" light is on but my brakes are fine.
 

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rock crawler
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If it is OK when cold, maybe the cold start injector is not shutting off and you're running too rich?
 

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If it is OK when cold, maybe the cold start injector is not shutting off and you're running too rich?
Ok here is an update on the problem.

Problem is intermittent, Ive been able to drive for a week with no problems, but then it happens.

I have pulled codes!!!!!!

I got codes:
62 - Severed No. 1 solenoid or short circuit – severed wire harness or short circuit
63 - Severed No.2 solenoid or short circuit – severed wire harness or short circuit
64 - Severed lock–up solenoid or short circuit – severed wire harness or short circuit

When the problem doesn't happen it shifts fine no problems or complaints. When the problem occurs i cannot rev past 2000rpm as if there is a rev limiter where the fuel injection cuts off.

Based off this information I am guessing that either my wiring harness is severed somewhere (but I can't find any exposed wires). OR. I am shorting out somewhere in that circuit and when the short happens it triggers the problem I am having. What should I be looking for?? What testing procedures should I do??
one thing that I have noticed is that the ECM and the solenoids all seem to ground out at the same point. Could my problem be a bad ground? If so I would have to take off the intake to get to it.

Any input will be greatly appreciated!!
 

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rock crawler
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Yes, a loose/dirty/bad ground can cause all kinds of problems.
Did you carefully inspect the wiring harness to the trans?
 

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Yes, a loose/dirty/bad ground can cause all kinds of problems.
Did you carefully inspect the wiring harness to the trans?
I suspect a faulty ground behind the passenger side valve cover between the firewall and plenum. I just got the tool to be able to reach it with my ratchet, and I will replace the grounds when it stops raining. The codes went away the day after they popped up, which makes me believe its a shotty ground because it seems to be causing some weird problems. I checked the wiring to the transmission pretty well and I did not see anything out of the ordinary. Thanks for the reply!
 

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There isn't enough slack in the ground wire for me to replace the terminal, so I just cleaned the terminal, washer, and connection point very well. Started it up and drove fine until i filled up for gas. After I filled her up I drove up the road and bam the surging happen. I noticed that when I fill up for gas there is a lot of pressure that comes out. ALSO the last 2 times the problem occurred was right after I filled up for gas. I already checked my fuel pressure while driving and if the pressure remains constant at 40psi WHILE the problem is occurring, then I rule out the fuel pump right? If the fuel pump was at fault wouldn't fuel pressure be rising and dropping while the problem occurs? Could this be fuel related? maybe a fuel pressure regulator?? I am still convinced on it being an electrical problem but i want to rule out fuel.
could the fuel pressure regulator cause a symptom of a rev limiter intermittently?
 

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rock crawler
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There is a pressure regulator and a pulse damper on the fuel rail.
As far as the 2000 rpm issue, maybe a problem with the TPS?
You could remove it and check it.
Also, how about a problem with one of the fuel line hoses.
There are 3, from tank/pump to the engine, a return, and a line to the evaporation canister.
If one were pinched, on wrong, or something it can cause problems.
 

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Hi guys, I'm new here and I do realize that this is an older thread. But, I was wondering if you ever found the problem, I have the exact same issue and it is driving (so to speak) me nuts.
Changed the TPS, Temp sensor, checked the cat back pressure, fuel pressure, etc.
 

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rock crawler
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The OP never got back with a solution.
Did you check out all the ground wires per one of the replies? That might help.
Also, since it's been quite a while, why don't you list all the specifics of your problem and what you've.
 

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Sorry it took so long to reply, I have a 95 4runner with the 3.0L 3VZE backed by an automatic tranny.

It will not pass 2000rpm. When it gets to 2000 rpm it hits the rev limiter and drops down to 1500rpm.
I have an OBD 1 reader and it came back with a code 42.
42 is the speed sensor, early 95's don't have the electronic speed sensors. It's still the cable drive speedos.
I have checked the cat for back pressure, fuel filter, fuel pressure, ground wires, etc. finally got to the coolant temp sensor, changed it out with
one I had in the shop and it seemed to fix the problem, for about a week, then the problem came back when I was on the highway, turned off the O/D and the problem went away for around 15 minutes then back again so I bought a NEW sensor, didn't help.
Pulled the connector off of the sensor in the block and connected it to the old sensor just laying on the intake.
Now revs to 3500 before it hits the rev limiter.
MAKING ME CRAZY.
Are there different temp sensors for early or late 95s??? Maybe I got the wrong one???
 

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rock crawler
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Even though you have a mechanical speedo there is still an electronic speed sensor (aka VSS) in the instrument cluster and 1-2 more in an auto transmission.
 

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I did pull the instrument cluster as well, everything in there seemed good. I took it apart all the way down to splitting the odometer from the speedo and cleaning everything. not sure where the tranny ones are on a non electronic speedo cable tranny, any help would be appreciated.
 

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rock crawler
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They are inside the transmission .
 
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