No power to injectors????

[lozt]

hey yall new to the forums and new to toyota's been wheelin for years but on fullsize chevys always wanted one and finally got one for my bday from my mom and her BF it's a 86 4 runner

My question is i have no power to the fuel injecters she will start right up off the prime and run for a few seconds but then she dies and i traced it to im not gettin any power to the injectors bein that i have never delt with Fuel injection was wonder in where i should start looking to fix the problem? where do the injectors get there power from?any help would be greatly helpful thanks

[yotanut7]

The power for the injectors comes from the solenoid resistor that is mounted on the passenger fender. It is a finned aluminum box with two connectors on it. That is turned on and off by the ignition switch. There are also wires that go from the injectors to the ecm. You could check those to make sure they are not loose but I would check out the solenoid resistor first. The recommended resistance between the plug with one wire and either wire in the other plug is 2 to 3 ohms.

[lozt]

ok i had some time to day to go over some stuff first thing i did was check that like you said and it read 3.4 after words i ran some checks to make sure that what i was told was correct about not having any power to the injectors when i pulled the injector plug and checked it for power with my test light is light up like the sun soooo i geuss the problem is somwhere else

so i checked for spark and she was sparkin like a champ and she is gettin fuel so im kinda at a loss for whats goin on never had to deal with any kinda computer of a car before timing seems to be right on she will start right up everytime but only for a few seconds anyone have any ideas?

[rsdan]

After my oil pump went out it would start and run fine, no knock for about 15-20 seconds then it would die. I never had any problem except that it would die after so long.

[lozt]

well did some more testin stuff today checked all the injectors they all seemed to be working checked the cold start dealy and it seemed to be working so i checked the fuel system so far i get fuel all the way to the fuel rail which to me would be a given for her to run but notin still. So i had a buddy come over and we used a can of startin fluid and she ran for a few mins sooo there is clearly spark and timing is good and i get fuel to the rail and i checked all the resistantes on all the injectors they were good so what would keep fuel from getting from the rail to the cylinder??? man im starting to understand now why i stuck to carbs and steered away form fuel injection this little 4 banger is drivin me nuts

[rsdan]

how old is the fuel?

[lozt]

fresh just added 10 bucks the other day

[Sean]

Check your air flow meter and knock sensor.

And when you checked to see if your injectors were firing what do you mean your test light lit up like the sun? Was it flashing? If it wasnt pull the plugs and see if they are wet.

[yotanut7]

If that checks out, check your ecu. You may be getting power to the injectors but the ecu acts as a switch on the negative side to complete the circuit. Also check the wiring itself between the injectors and the ecu. Make sure the ecu is grounded well and the resistance of each injector should be 1.5 to 3 ohms. If all of this checks out, try another ecu. These are the tips from the FSM. If you don't have any buddies with an ecu you can borrow, check the junkyards. I got mine for 10 bucks.

[lozt]

well when i pulled the injector power plug and stuck the light to it it was just a constant light no flashing or flickering just on like a lightbulb i did pull one of the plugs didnt seem to be wet at all but i will have to double check that again today

as for the ecu i will have to try that out ill see about hittin up a junkyard for one i did check the resistance of each injector and they all came out to 3.4 ohm would .4 over be a problem?i have read that anywhere from 1.5-4 ohm is ok but who can trust the shit you find on the net these days

thanks again for the help this is a whole new world for me ill keep ya posted on how she goes

[jkc824]

i had the same problem, put a new computer in it and it ran fine.

[lozt]

ok well i will give the new computer a shot called all around to the wreckin yards today and cheapest one is 75 bucks didnt really wana get it unless i was pretty sure that was the problem so ill give it a shot and see what happens thanks for the post

[Justin]

I had an old ford with the same problem it was the fuel pressure regulator.