The last few days my wifes 4runner has had a hard time starting. It's a 1991 4runner v6 3.0efi auto
You turn the key and it sounds like no spark or fuel, it just turns over. I can pump the gas still nothing. I don't smell fuel out the exhaust like it's flooding + it's FI.
It has a new cap, rotor, plugs, wires all changed a year ago and ran fine till now. If I turn the key off and try again sometimes it works some times it just does the same thing, the turning over no fire. When it does fire she runs smooth and seem to go. I have had it stall after it starts for a coupe of mins then I try to start and same thing no fire. When it runs for a bit it seems to stay running. The check engine light doesn't come on. The only thing different I had done was fill the tank and add the proper amout of this: http://www.amsoil.com/storefront/api.aspx to give it a clean out and help for Air care. It went thru Air care fine. The only thing I can think, something got loose in the fuel system and is blocking some where but then when running she runs fine. I can't think what it would be right now any thoughts or checks.
Thanks.

 

When it doesn't start try pulling the fuel line off the regulator on the drivers side and put it back on...then crank it up and see if it starts. Mine did that every now and then. Thought it might be the damper on the back of the fuel rail that was limiting my fuel flow when the adjusting screw in the middle of it fell out in the cap. Another thing is try pulling the gas cap. Might be vapor locking on ya.

 

check the Air flow sensor connector. It's a connector on top of the air filter canister.

 

My wife a hard time starting it Thurs morning and again before she left work that afternoon. She finally got it going and picked me. We had some things to get done so we could get away Friday. On to our first stop, my wife left the rig running while she ran in, I waited, it sounded fine.
Second stop I turned the ignition off. I then tried starting it right away, nothing. I left it till my wife came out and nothing, left it for 20min, 30min, 1hr, during that time I checked for loose wires and pulled fuses. All fuses still had the dielectrical grease I put on a few years ago and looked clean, no connections loose.
I was realy starting to think that maybe the fuel pump was going and the injector cleaner screwed it up or cloged a fuel line. My wife had the fuel filter change before we met 4.5 years ago but it could be clogged, I was guessing.
I then pulled a plug wire to see for spark nothing. I plulled the coil wire to disrtibutor and nothing. I decided it was time to call the tow truck and have it pulled to my house. We left for the weekend and I tried it when we got back last night. Still nothing and no spark at coil.
I went through the wiring again for loose conection but could not see or feel any. Got to dark and to bed I went.
Is there any checks for the coil?
Do you think it's anything else causing the coil to not spark?
More checks?
Thanks guys.

 

this is a long shot but try it with a jumper cable....

 

Could be the coil, or the ignitor. I can send you the testing procedure from the FSM, might help you narrow it down. If you want a copy send me an email address.

 

ive been having similar problems. '91 3.0- would start sometimes, and then not at all. eventually it just wouldnt start at all. started trouble shooting and found the distributor had died. replaced it and now it starts again. played w/ the timing yesterday, but it is still slow to start! since yours isnt running, you could get a hold of a multi-meter and start taking resistance measurements as per a chilton's/ hayne's etc...
i started with the ignitor and ignition coil and moved towards the distributor. now that i can at least get itt running again ill start looking for vacuum leaks and replace the pvc valve. keep in mind that ive never worked on cars before- just reading a ton and learning all i can. hope this helps!

 

Is it only giving you trouble when its COLD OUTSIDE ?

If this is the case its either your Cold Start Injector (Highly unlikely)
OR your Cold Start Injector Timming switch. (VERY LIKELY)

This Timming switch acts like a Choke, and adds more fuel when its cold.

Search the forums, theres a write up on here somewhere as how to test the timming switch, (You basically check the resistance with an Ohmm reader)
(Sorry the one I have is for the 22RE)

 

start with the obvious, put in a new fuel pump and change the filter. I've had the pump go out slowly, sounds like it to me.

 

No, cold or hot or even after it's run up to temp. She still not firing.
Now the thing is completely dead.
Not spark out the coil what so ever.

 

I have checked for resistance at the coil. These are the numbers.
Primary resistance check was .8 to.7 ohms Haynes book says it should be .4 to .5 ohms
Secondary resistance check was 12.3K ohms Haynes book says between 10.2 to 13.8K ohms
Insulation resistance check was infinity Haynes book says infinity (at least more than 10m).
Only the primary resistance is off, would that be enough to cause it not to start or would it just run rough?
Does anyone know how to check the igniter?
Next I will see about fuel being pumped thru.
Any other Ideas. The coil is no biggy at 66$ Canadian.
The igniter is well over 250$. A used coil/igniter together at the wrecker is 125$ but what if it's on it's last leg aswell.
I will also try and do a code check tonight.
Would a bad fuel pump cause the no spark?
The fues block under the hood on the pasanges fender has a EFI relay or something that I remember pulling at one time when we went on a holiday so no one would be able to start it. Of couarse I put it back when we returned other wize it would not start. Could this relay have gone bad?

 

man, mine was giving me the same symptoms before it went completely dead. have you checked the distributor yet? now that i changed that out it starts, but still slowly, smells very rich, and i think its not up to full power. i started to check other stuff like the air valve ( or idle air control? ) and it was need giving me the wrong resistance reading per hayne's/chilton's. was gonna check other stuff but im fed up so im just going to the stealership for a diagnostic saturday. ill post the results. please let me know if u figure anything out.

 

I first checked the EFI relay I mentioned, it's fine.
So I put the coil and igniter back in and hook it all back up to check the codes.
I did a diagnositc check as per this artical. http://www.off-road.com/toyota/tech/codes/index.html
I first turn the key to the ON position and go put a jumper wire in the diagnositc box. The check engine light just blinked away, over 100 flashes in a row. I figured this ain't right so I shut the key off.
I then figured I might have to try it with the key off then turn it on. Nothing, No light came on. I then try different things like turn key to on then off then on, pull jumper and put it back etc. etc.
Lastly I'm fed up and pull the jumper from the diagnositc plug and wonder if she will start. Fires right up. Runs fine everything sounds good. I rev it up, all still good. Go for a drive then return home and shut it off. She ran fine.
I then try to start it and nothing it just turns over.
I figure it might have to do with the igniter. I thought maybe I'll try just what I did with the diagnositc check. Guess what it fired up and ran fine. So I turn it off and did it again, nothing, just cranks away. I do a repeat of the check. This time nothing.
I also noticed now a fait high pitch whistle now when I crank, coming from under the dash. I know it is a electronic whistle sound, on and off with the key. It was never there before.
What's your thoughts.
If I find anything, I will post it here.
Thanks for all the help.

 

where under the dash? is it the ecm or the ignition relay on the passenger side? those are the only ignition elec components i know of behind the dash. - cheers

 

The EFI relay I'm refering to is under the hood passangers side. It's in the fuse block. A round relay. It's used for the EFI fuel pump.

 

Symptoms still there.
I changed the igniter still has the starting problem once in awhile.
Took coil to get checked in case I was doing it wrong, it's good. How wrong can a two wire ohm test be.
The EFI relay does what a relay should (bench tested) plus I don't think that there would be no spark, it's for the fuel pump.
I get fuel at the rail. It's definitly no spark.
I'm thinking maybe a sensor telling it not to fire, crank position or I don't know.
I can not get the codes to run as stated above, I have tried a bunch of different ways.
When running it rund fine.
I guess it's going to go in for a diagnostic check next week, I'll call the dealer monday to book an appointment.
This is stupid. Works fine for a few starts then the cranking over no spark. One day good next day crank. It's no wonder I feel like working it over with an axe, but we know that won't help.
Thanks for the input guys.

 

Charger92 I had the same d*mn problem with my 95 Hilux 3.0 4x4 pickup.

There are two fuel relays. One under the hood and the other under the dash between the key switch and center dash vent system. It's a little bugger (relay) to get to.

There's a point when the relay gets to hot and will not activate. I replaced both, under good and under dash relays and all was good for over 75,000 when I sold it.

This little relay is missed in most electrical diagrams.

Good luck!

 

Would the relay cause there to be no spark out the coil?

 

No, relay provides current to fuel pump.