HELP! 89 4Runner 22RE Auto, no injectors!
 

Just replaced a broken timing chain and during the winter when I was diagnosing it I tried an ECU, ignitor, new fuel pump, starter, added starter relay before I finally figured out the chain was broken. New timing cover, new chain and guides, new head gasket and head bolts and upper intake gaskets, dropped the oil pan to clean the screen and all the chunks out. When I got it all back together (with the ECU I had swapped in still there) it fired up with a constant check engine light and ran poorly. Took it for a drive and would not shift gears (its an automatic) and brought it home and let it run a bit to get the battery charged up.


Came back to it the next day and it would not fire. Turned over fine but no fuel. Figured the ECU sold to me was actually for a manual and put the original back in. Now no constant engine check light, but still no fire. Lot's of fuel pressure to the rail, will run beautifully with some starter fluid. Just no injectors shooting!. Have a Code 22 and replaced the temp sensor that probably wasn't bad.


This truck is so good when its on the road! Please help me figure this out for my daughter!!! Thanks in advance. Usually, I can find what I need in the threads but I have gotten to the end of my rope...

Did you get the ground wire back on the intake manifold? If it is not hooked up or not tight, your injectors cant fire with it. Here is what I went thru on non firing injectors https://www.yotatech.com/forums/f199...l#post51897320

There are two sides, Fire side which is on the spark plugs, coil,... and Fuel side which is what you are saying. Only time I ever see a ECU failing is when it gets wet, there is always a chance that yours failed but it would be the last on my list of failed parts.

Thanks Terry87! I'd like to say those are all good, but... I recall specifically all of those points. I also added some heavy aux grounds between the head and block and body way back in the past. Makes sense about the grounds- may have arced a bit after it ran last time if loose. Would that lead to the Code 22 pulling up? Incidentally, the OBD is working well, first time I ran for codes I also got 51 (the AC power button was on).


Won't be back into town to check until Friday and will let you know then. Could a loosely mounted ecu not provide ground for that as well? I had a helper install that back and I noticed He didn't tighten it down.

I had my kid check the grounds and they are well fastened. It did run for a day with the other ecu. Have any ideas what could have happened from the day of running to the next day of not starting? Efi fuse is good.

I have had the ECU just laying in the floor and not bolted down for troubleshooting and no problems. Some of the rock crawlers move them to the glove box to avoid getting them wet when crossing water and I don't think they ground them in the glove box, just mount them so they don't bounce around.

Code 22 is a Water Temperature Circuit fault. Cant see it not letting the truck not start unless it is shorting something out and blowing a fuse. It should be the green sensor just below the thermostat housing. Check the connection and wiring on it and see if it is frayed.

When you say it wont start, will the motor even crank? Are you getting fire to the plugs? Just want to get the information to see if it is an injector issue. Timing and plug wires are correct?

I figured on the ecu. Yes, spark is strong and it cranks and runs smooth for as long as the starter fluid lasts. I haven't checked: efi main fuse, efi relay, main relay, cor relay yet. I will be able to tomorrow. Failing that, I have the FSM to check all the points at the ecu harness and other points.

Any other suggestions to check?

With a multimeter, that is...

I went and see you have fuel pressure at the rail so that rules out the fuel pump. If it was me, I would get the $3 Noid light in the link above and see if the computer is sending the signal to the injector. If the computer is sending the signal, the crimps in the harness wont pass all the voltage that is needed to fire the injectors. The harness can get moisture in it and that may at times help or hurt it with enough continuity to make them fire or not at times. Electrical is not my strongest area but can stumble my way thru some of it.

Have you ran any fuel cleaners thru the tank? A member on here ran some thru his tank and it clogged his injectors. The tanks in these trucks get dirty. It may look like rust in the tank but I think it is a chemical build up that in in the gas. In each of my builds below in my signature, I show how bad the tanks get in these.

With a syringe, a hose and a 9 volt battery and carb cleaner, you can test and flush the injectors. Just apply power to the injector for 1 second at a time.

I am thinking you may be getting a weak signal or gunk in the injectors that when it is running, it is just enough to make it run but would die out if revved up higher then the gas flow could provide with debris in the injectors.

Well... turns out a battery that seems fully charged on a charger may not have enough amperage. Swapped another battery in and held throttle while starting with starter fluid- it ran and kept running, tho idling poorly. Took off the iac to clean. Will see if that helps the idle.

Also, I can't get the jumper to do anything when I am setting timing. Seems to be running rich. Unplugging the cold start valve does not affect it.