96 4runner no start.. scan tool link error..has spark and fuel
#1
96 4runner no start.. scan tool link error..has spark and fuel
I have read numerous threads pertaining to non starting vehicles. So far I have not found a solution. I have a 1996 4runner sr5, 130k, v6, auto, 2wd. The vehicle has been very reliable and just stopped starting all of a sudden. I was driving on the highway, got off and parked at the store. Ran perfect. Came out and would not start. I have good spark and fuel. I also can smell unburned fuel coming out of the exhaust. I know fuel is getting to the cylinders. I tried to check the ecu, via obdii connector under the dash, with my scan tool (which has been verified working on another vehicle). I get a communication error. I have never had a check engine light come on since I bought the truck. I took the ecu out and it looks like brand new on the inside. The only other thing that is different, is the IAC is making a loud buzzing/ticking noise with key on, engine off. It never did that before. From what I read its supposed to make some noise. Can the IAC cause a no start problem? I thought a vehicle can run even if the IAC messed up. So I am leaning toward the ecu being toast. Any suggestions? Thanks in advance.
edit: I also confirmed that all fuses and relays are functional.
edit: I also confirmed that all fuses and relays are functional.
Last edited by xdescrubx; 11-19-2016 at 11:19 AM.
#2
Registered User
iTrader: (1)
Just what do your plugs look like??
About the only thing that will take out the ECM is getting water inside or a massive voltage spike
Some contact cleaner should cure your failure to connect
The MIL light does light when you turn the ignition switch on?? So you know the bulb is working ??
About the only thing that will take out the ECM is getting water inside or a massive voltage spike
Some contact cleaner should cure your failure to connect
The MIL light does light when you turn the ignition switch on?? So you know the bulb is working ??
#3
The MIL does come on when key is on/engine off. I cleaned the obdii connector with electrical contact spray. I cleaned the IAC and throttle body. Spark plugs look good. There is unburnt fuel smell in the cylinder. Still cannot connect to the ECU. I get power at the plug but no link via scantool. I put everything back together and It still doesnt want to start. I sounds like it may want to start for a millisecond. It seems the engine is getting flooded enough to where its loosing compression due fuel washing oil out of the rings. Can a faulty ECU cause a rich condition?
#4
Registered User
iTrader: (1)
Anything is possible
One thing I forgot is physical damage to the wiring harness
Rodents chewing wires is quite possible
something shorted and burned
poor ground connection
Then since you have not caused a code to trip
injectors stuck open can fill cylinders with fuel
One thing I forgot is physical damage to the wiring harness
Rodents chewing wires is quite possible
something shorted and burned
poor ground connection
Then since you have not caused a code to trip
injectors stuck open can fill cylinders with fuel
#5
Thanks for the reply. I thought about the injectors, but what's the chances of multiple injectors stuck open? I wouldn't even suspect the ECU, if I could communicate with it on my scantool. I think i'm going to order one off ebay...30 day money back guarantee. See what happens. Ill post results.