1986 4Runner ECU issues

[pmac-VT]

I am pulling my hair out....I am getting a code 11 and have not been able to isolate the problem. I started at the obvious places, fuses, relays, fuel.

There is power to the cold start injector but I can not seem to detect pulses to the main injectors. I have a number of part rigs, so I was able to try different injectors, relays, solenoids etc. I even try 2 different ECU's (3 total) and another wiring harness from the ECU to the injectors, sensors, ignitor.

Same code, same problem, will only run intially of the cold start injector. I have even tried to isolate if there may be a problem with the ignition switch.

Any suggestions?

 

[regularguy412]

"While a lot of the possible faults in the EFI system point to the ECU iteself, it should be noted that ECU failure is not common. The ECU should be replaced only as a last resort or if all diagnosises points to a bad ECU. Usually, troublesome EFI problems are a result of poor grounds, shorted wiring, and bad connectons at sensors.When all else fails, carefully consult your factory repair manual. It contains more comprehensive diagnostic information and great electrical wiring diagrams."

The abover are not my words. They came from here:

http://www.off-road.com/toyota/tech/codes/index.html

I assume you have a sufficient amount of fuel pressure. I had a similar problem,, hard starting after overnight cold. I would have to try it several times, before it would continue to run. The 4R would buck and jerk occasionally during acceleration,, especially when starting up from a dead stop. Turned out I had a bad fuel pump. I changed the fuel filter right after purchasing my 1992 3.0, 2 yrs ago. However, I bet the previous owner hadn't changed the filter in the 145,000 miles that were showing,, and the excess backpressure wore out the pump.

If your pressure is good,, then I'd look for shorts in the EFI wiring.

Mike in AR

 

[Quakefire]

where is the cld start injector, because when my truck is cold she stalls out under acceleration/idle, and that injector is on my list of probable cause

 

[pmac-VT]

I talked to a local mechanic friend of my who suggested looking at the distributor. He seems to recall that the main injectors are powered from the distributor.

Its worth a try.

Cold start injector location on a 1990 4Runner? does it have a 22R engine?

 

[Quakefire]

No it has the 3.slow i'd prolly be having less problems if it had the 22re

 

[Sidney]

The Throttle body needs cleaning:

To clean the throttle body remove the air intake hose and examine the intake and throttle body for excessive carbon build up if found then buy a can of throttle body cleaner labeled "safe on oxygen sensors,TPS's and catalytic converters" do not use carb cleaner make sure your engine is fully warmed up prior to using as when the throttle body is hot it dissolves the carbon easily and quickly.The labels usually specify to park the vehicle at ground level (0 degrees,no inclination) and have the engine running but I disagree I instead park the vehicle on a hill facing down and shut the engine off and hold a rag below the lip of the throttle body and poor the stuff and use a tooth brush.

If problem persists the TPS then needs adjusting:

http://4crawler.com/4x4/CheapTricks/TPS/index.shtml

and then use a timing light to make sure your timing does not get retarded and cause overheat episodes.

http://4crawler.com/4x4/CheapTricks/TPS/index.shtml

Sidney

 

[pmac-VT]

:bash:
Damn..I had the throddle body off to swap the TPS....and contenplated using the other throttle body.

I can not heat the engine up to use the cleaner as i am still not getting any pulse at the injectors. (will only run on the cold start injector then die)

I will change the throttle body and see what happens...

 

[ricofreako]

at least you get a code, my ecu just stops working whenever it pleases. I often cant start my car because of it. Yet it throws no codes, no check engine light.

 

[super-secret]

The Throttle body needs cleaning:

To clean the throttle body remove the air intake hose and examine the intake and throttle body for excessive carbon build up if found then buy a can of throttle body cleaner labeled "safe on oxygen sensors,TPS's and catalytic converters" do not use carb cleaner make sure your engine is fully warmed up prior to using as when the throttle body is hot it dissolves the carbon easily and quickly.The labels usually specify to park the vehicle at ground level (0 degrees,no inclination) and have the engine running but I disagree I instead park the vehicle on a hill facing down and shut the engine off and hold a rag below the lip of the throttle body and poor the stuff and use a tooth brush.

If problem persists the TPS then needs adjusting:

Toyota 22RE Throttle Position Sensor

and then use a timing light to make sure your timing does not get retarded and cause overheat episodes.

Toyota 22RE Throttle Position Sensor

Sidney

I agree with adjusting the tps. Main thing is to check resistance on VCC and E2 legs. If it shows infinite, replace TPS

 

[Kean]

.....this thread is 10 years old guys.

 

[Fuegorunner]

86 Toyota 4Runner sr5

So I got this truck off my neighbor who had it sitting for 10 years or so. I connected everything it needed back on to the engine. I tried putting the engine on top dead center and adjusting the rotor to cylinder 1. But it still won’t turn on it’ll crank but it doesn’t want to turn on. Any advice

 

[Reinout]

So I got this truck off my neighbor who had it sitting for 10 years or so. I connected everything it needed back on to the engine. I tried putting the engine on top dead center and adjusting the rotor to cylinder 1. But it still won’t turn on it’ll crank but it doesn’t want to turn on. Any advice

Hi, I'd suggest starting a new thread about this and not on a thread started in 2006. You'll also want to give more details on symptoms, what was disconnected/reconnected. etc.

 

[Cobelle]

Newbie

Hey all, new member and first post, so not sure I'm in the right place.

I have a 93 3.0 V6 that just died while driving like I turned the key off. After sitting (usually overnight) it would start and run fine in park (AT), then die after 5-10 minutes. Fast forward several months after testing throttle position sensor and MAF, changing temp sensors and whatever other sensors sit on the manifold at the rear of the motor, again starts fine but dies within a couple minutes. When I jump FP-B+, I get fuel coming out of regulator, but won't start with that jumpered after it has died. Trying to figure out what I am missing, and if I'm down to COR or ECM. Any advanced help would be much appreciated. And if this isn't the best place to post this, feel free to give suggestions.