surfin cj7

Hello everybody,

History:

I helped my buddy purchase an 1987 4Runner with ~165,000 miles about a month back and we have been trying to get the rig running. The previous owner thought he had a head gasket issue so he replaced the head gasket but in the process stripped a bolt on the lower intake manifold where one of the coolant lines is connected.
We replaced the intake manifold and started it up and let it run for a few minutes. We shut it off to check the coolant and oil levels and found that the "milk shake" had appeared. Long story short the guides were broken on the timing chain so we replaced the timing chain cover, chain, guides, etc. and tried to start it up and now it will only crank but not start. I have searched and used other threads and FSM to conduct troubleshooting and based on that troubleshooting below I believe the fuel injectors are not getting the ground signal from the ECU and the cold start injector is not getting the right signal but have not been able to fix it.

Completed troubleshooting:

Spark/timing
- I get good spark at the plugs when cranking the engine (grounded to block)
- I have verified TDC, made sure the timing mark was at zero and the rotor was pointing at 11:30. atleast 5 times.
- I have double checked the wiring & firing order
- 175 psi compression on all four cylinders

Air
- I have checked the voltages & resistances listed for the AFM and all within spec
- the intake tube is in good shape
- all vacuum hoses connected and in okay shape

Fuel
- Fuel pump is heard when key is in "on"
- Fuel pressure is 38 psi after fuel filter going to fuel rail.
- Fuel injectors and cold start injector "fire" when battery power and ground applied to terminal.
- Truck starts and runs until starting fluid burns off when starting fluid sprayed into CSI hole

Electrical
- All fuses checked and looked good
- New EFI main relay installed
- New Circuit Opening Relay
- Solenoid resistor checked, input and output voltages within spec
- known working ecu swapped in
- dedicated ground from fuel injector harness to neg battery ran (ground normally connects to manifold)
- same voltage out of solenoid resistor to fuel injector connectors (not a splice issue then?)

ECU checks (per FSM)
- voltage in specs at +B - E1
- voltage in specs at BATT - E1
- voltage in specs at IDL - E2
- voltage in specs at Vcc - E2
- voltage in specs at VTA - E2 with throttle valve closed
- voltage not in spec at VTA - E2 with throttle valve fully open
- voltage in specs at STA - E1
- voltage in specs at No. 10 - E01 & No. 20 -E02
- voltage in specs at Vc - E2
- voltage in specs at Vs - E2 with measure plate fully open & closed
- voltage in specs THA - E2

I could not do any voltage checks that were done at idle obviously and didn't check coolant temperature voltage.

Things left to do/check:

The ECU is giving fault codes 4 & 11.

4 = TPS sensor fault
11 = coolant temperature

I am going to get a new TPS sensor and have another coolant sensor to install.

Again, it appears that the injectors have the correct voltage but are not receiving the "ground" signal to fire. Also the cold start injector is not firing.

Any suggestions for additional tests or checks would be appreciated. We want to get this puppy running soon b/c the temporary registration is about to expire.

Thanks,
Matt

surfin cj7

Doh it's a 22RE

scope103

If only everyone asking a question on this site had done their home work so carefully ....

Alas, I'm not sure what else to look for. Have you tried putting a stethoscope (a piece of vacuum hose in your ear will work fine) on the injectors while running with starting fluid, just to listen for the clicking? Have you tried a "noid" light to verify that you have voltage, but no switched ground, to the injectors? Are your spark plugs dry (indicating no fuel -- if they're wet that suggests a spark problem)?

Good luck!

riddarunner

A friend of mine and i just went through this with his runner tired a lit of stuff then found 2 clogged injectors and the "main relay" stamped "M4" on the driverside kick. is the check engin light comming on with the key? if not it would be a good indcation thst the m4 relay is bad. no signs of water and ours was rusted on the inside.

Terrys87

iTrader: (1)

Hello surfin...I went through about the same issue as you and seems you checked alot of the same things I did. On my 86 build, some of the more recent pages, my injectors werent firing.

I am betting the wiring clips inside your harness are really corroded. I rewired,soldered and shrink wrapped the connections.

Also I ran a ground wire from the external of the ECU to a good ground. I am not sure how much good the new ground did for me but it couldnt hurt anything.

Here is what all I did, but think it will be your connectors in your harness. Page 12 of my 86 build has a few more pics.

------------------------------------------------------------------------------------
This is going to be my Fuel Injector notes page.

Good wiring diagram...........https://www.yotatech.com/forums/f115...e-help-178975/

Different Injectors.............https://www.yotatech.com/forums/f116...ectors-127606/

Correct Ground Locations....https://www.yotatech.com/forums/f116...-guide-194413/

Pinout for ECU.... ..............http://media.photobucket.com/image/1...outdiagram.jpg

Add Ground to ECU by Trailgear..http://www.trail-gear.com/vbulletin/...ead.php?t=9973
Redo wire connections.
Externally Ground ECU.
Check all grounds........................................... .................................................. .........................Missing ground from Positive Cable. Will get one from bone yard. All other grounds installed, plus I added another ground.
Check wire harness ground on intake manifold.......................................... .......................................Checked Good
Check Solenoid Resistor. Haynes page 4-10 13.22b............................................ .............................Tested Good, supposed to have 2-3 Ohms, I have 3 Ohms.
Check EFI Main Relay Haynes page 4-9................................................. ........................................Tested Good Supposed to have 60-80, I have 71 Ohms.
Ohms for 86 Injectors are 1.5-3.0 all others are listed on page 4-2................................................. .....All tested 3 Ohms.
Run resistance checks on harness........................................... .................................................. .......Still running resisitance checks. Also I am soldering connections in harness.
#10 and #20 are apparently the ground pins on ECU. Hoping not have to go that far.


Here is something I found on Toyota Nation. Sounds alot like my problem.

[Quote]I found the problem!!! The ECU and Igniter are not component that fail very often, the problem is the wire. The main engine harness contains two wires from the ECU that are spliced and split into 4 wires at the injectors. For some reason Toyota decided to splice this circuit inside the largest portion of the wire bundle. The problem with this is that where the two wires (white with blue tracer, and white with red tracer) from the ECU are spliced with the four wires from the injectors(same colors as above), the insulation is removed exposing the copper conductor to potential corrosion and breakage. Upon inspection, these wires may appear to be fine, and may even ring out when tested with a continuity meter, but in my case, the corrosion had progressed beneath the wire insulation for 8-10 inches, and compromised the copper and it's ability to carry the pulse signal to ground through the ECU circuit.
The fix is to remove the tape and protective coating from the main harness between the intake manifold and the fuse box under the hood, you may notice green corrosion on the wires in question where the mechanical crimp splice is made. 10-12 inches of these wires may need to be removed and replaced with new copper conductors. Both sets of conductors from the injectors are common, so you'll need to figure out how to properly connect the two leads from the ECU to the 4 leads from the injectors. In my case I trimmed the wire back until I had good continuity to both ends, and soldered new leads on, encasing them in 3M scothcote electrical coating and heat shrink insulated tubing.

My 87 4Runner runs like a charm. I still can't believe Toyota engineered it that way, but this fix is much cheaper than replacing igniters and ECU's. Hope this helps anyone/everyone. [Quote}

Jagman60

Hey, I have a similar problem I have been fighting for a while. Worked on it again today. I have spark, and engine will run on eather. I have good fuel pressure to the rail. The injectors do not fire. I have checked the injectors and the wiring. I can make the injectors click by touching a ground to the wire "no 10" and "no 20" coming off the ecu. It seems the ECU is not giving the signal to the injectors to fire. What tells the ECU to fire? Does it get a signal from the distributer? Or is there a flywheel position sensor someplace? I have been trying to locate another ECU but it seems I have a rare one, not same as any on Ebay. Can anyone help?

Kiroshu

Check Signal wire(s) running from Ignitor/coil assembly across exhaust manifold, over valve cover into the intake manfold wiring harness for an open/short to ground.

This will cause the injectors not to have any signal from ecu.

Check coolant temp sensor and cold start time switch connectors and make sure they are not "swapped" this will also cause a faulty injector to ecu signal.

Seeing the coolant code in the computer more than likely may be the problem...

^_^

Jagman60

I checked the coolant temp sensor and the cold start time switch, they are color coded, one is green and the other is black, they seem correct. As for the wires running across the engine, do you know which carries the signal and where I can check on the other end? This truck has been down for months.

ChefYota4x4

iTrader: (5)

Wow, OP, ....PROPS! My first post was 'YADDA YADDA, BLAH BLAH, ... HELP!', lol. I've leared a bit, since, and what Kiroshu and Terry have posted have seemed to be the most common causes(along with just simply forgetting to connect the "LONG" ignitor wire that Kiroshu described... Which is insulated, but CONSTANTLY laying over one of the hottest portions that wiring has to endure, including where it runs right over the exhaust manifold)...

Terry has me wanting to rip into my Harness just to be sure on some stuff that might explain an intermittent/erratic miss I have.... Others have me thinking I should also be looking, AGAIN, into the fuel pressure/CSI leakage possibility, etc.. GOTTA LOVE YOTATECH! Watching, and best wishes, man!

ChefYota4x4

iTrader: (5)

I went through some of this testing my troubleshooting thread/build thread.. but don't bother searching, they're BIBLICAL - LONG! lol. LOOKS like you went through that portion of the 'voltage testing at ECU', in the Ignition Section of the FSM? I THINK it's in the portion where IGN testing is done at the ECU. It's split up in the FSM, between Voltage and Resistance testing.... Obviously you can't test "while running" portions... But maybe if you can find 'that one' spot in the IGN FSM testing at the ECU where it's 'dead or questionable', HOPEFULLY you're onto something and you'll find it soon! Rooting for ya, JAG!

Jagman60

You mention a wire going from the igniter across the engine, is that how the ecu knows to fire the injectors? I am getting 4 healthy sparks so I know something is getting across. I will look some more at that portion of the harness. Problem is I received this truck in pieces with the engine in the bed, so I dont know if I am missing anything. Wife is kind of bitching about it sitting in the driveway. There are two sensors of some sort missing on the front end of the valve cover, the plugs are hanging there with nothing connected. Have not been able to figure that out ether. I tried shorting them to see if it would work but no luck.

ChefYota4x4

iTrader: (5)

Well, my buddy had torn down many times, etc., looking for 'gremlins'... and he'd forgotten to connect that wire to the ignitor/coil, across the engine..... Connected it, and VROOM! Obviously, you're being VERY thorough, but now, after reading your last post.... has me curious what might be 'off' or 'iffy' or 'missing' a connection, ya know?

Are you speaking of the 'VSV's' on the top of the valve cover? One in front is for AC... the other(should be at the rear most portion of the top of the V-cover, is the Fuel Pressure Regulator VSV. I'm not sure, but I doubt either of those would prevent you starting. Roger/4Crawler has deleted his FPR - VSV, he runs just fine connecting the FPR directly to the Plenum. the AC vsv? REALLY doubt that would cause a no-start. They're not really sensors as much as 'Vacuum Switching Valves'... But they DO have a total of 4 vacuum lines running to and from them, combined.(AC has 2 that run to plenum and VSV-FRP has 2, one from plenum and one to FPR).

The longer wire running up through the plenum, out of the harness that runs over the motor and to the Ignitor... that is CRITICAL... but I'm not certain if you can still have spark without it connected... What I THINK is possible, however, is that IF it does 'SPARK' without it connected(or some compromise), then it has a crucial relationship with the injectors as in 'when to fire', along with the Dizzy, etc. Your Dizzy is obviously connected, otherwise you'd not have "4 hot sparks" as you said. I'd definitely look into the ignitor wiring to be CERTAIN it's not compromised. I mean, can't LOSE anything making sure, right?

PS> A buddy of mine had his Dizzy in 180* off... it would spark like a shorted socket, ....but NO FUEL. He flipped it along with replacing the wiring Terry had explained, above... Purrs like a kitten now. Even in the FSM, there is a diagram/picture of a guy wiggling that horseshoe portion/thick portion/ of the harness. I believe they're looking for causes of 'missing'/'trouble' within there... But OBVIOUSLY, you can't be SURE there's no corrosion, etc., without ripping into it, right? I'd test everything mentioned, first, before tearing into that. BUT, since you've spent monthsssssss with this down... What's a day or two tracking down wiring, right? lol.

ChefYota4x4

iTrader: (5)

PS> As I said, I'm not sure if you can get spark with a 'compromised' ignitor/ignitor wiring/...... So yeah, I'd have to double check on that one. BUT, the coil and dizzy are what relate the spark from one to another, in the most basic way(Not the same as a "POINTS" dizzy, but when the dizzy point on the shaft hits the contact(secondary?), then through the secondary coil, etc., the coil fires back to the dizzy cap, etc. RIGHT? lol.. the ignitor, IIRC, DOES, INDEED have lots to do/maybe everything to do/ with when the injectors are to fire. Then, the solenoid resistor has it's part, etc., etc., right?

Just thinking out loud.. been a while since I dug into the ECU stuff. (might be having to again, soon, just like you! lol)

ChefYota4x4

iTrader: (5)

OK, VSV to Fuel Pressure Regulator(back/driver side of Valve Cover)....


AC VSV(toward front/driver side of valve cover).........


Ignitor Wire(end of LONG wire and it's connector to the ignitor...


One end of 'wire to ignitor from dizzy'...


Other end, Ignitor side of 'wire from ignitor to dizzy'...


The longer wire travels over the valve cover to the ignitor, from the harness..... It's all related and works together to determine 'spark timing', but I believe the ignitor also 'relays' the message to the ECU as to 'when to fire the injectors' in relation to the spark timing... ????

Kiroshu

^-- Yes ignitor signals injectors.

I know this from personal exp.

About 2 years ago i would be driving my truck regularly as i always and all of the sudden i was sitting at a traffic light and it just cut off....

Atempted to re-start it numerous times while sitting at a green light with 5 car horns behind me blazzing... after about the 15th crank it started and was fine all the way home(20 miles).

It then happened a few weeks later my school parking lot and it would not re-start at all... i had to have a guy in a ford f-250 drag me over to my shop >_<

Very emberassing....

After the truck sat for 4 hours it re-started and was fine for a few months...

I figured it was... an intermidate connection problem somewhere and since it was doing fine i didn't bother...

However after a few months... it happened again... only this time i was going about 65mph on I-95... the truck lost all power and bogged down completely and finally cut off... so i rolled to the side of the interstate... and in my head i kept thinking it was the AFM.

I had a few tools and my haynes manual with me so... with it being 9:00 at night and raining on the side of I-95 i proceeded to find the problem...

The truck this time would not re-start... i spun that life time warranty starter over 30 times...

The AFM tested good along with many other numerous sensors...

the truck would start off an alterative fuel sprayed into the intake but of course being 10miles from the house i couldn't exactlly do this all the way home...

So i let the truck sit there till the morning... had to walk home in the rain... >_<

Next morning i got my step dad and his truck to go out with me to get it and pull me home... we tried to start it then and i would not crank still....

The truck would still not crank after a few days of investgating......

I knew all the physical sensors, motors, fuel pump, and engine were all healthy...

I knew it was a fuel problem and proceeded the 6 hour begining of tracing wire(s)...

Sure enough i found that the wire that chef is pointing to in his 3rd picture was broken/cut right were it rubs on the edge of the valve cover....

Reconnected the wires and VROOM VROOM. Fixed and haven't had a problem since...

Sorry for the long posting >_< hope this helps...

ChefYota4x4

iTrader: (5)

Woot!

Now THAT'S a crummy adventure through 'GREMLINVILLE'! lol.

Jagman60

OK, Checked some more stuff, There is a plug going to the igniter from the harness. It has five wires, a black, black/red, black blue, black/yellow and black/brown. The blue, brown and yellow go to the ecu, all have perfect continuity and no ground. The black/red is a little heavier gage, it comes out over near the ecu in another plug over on the right side passenger. I unplugged it and tetsed, it has perfect continuity but a 25 Meg Ohm to ground, thats weird. When it is plugged in it has 73 ohms to ground. As for the last wire plainblack, I am still looking. No ground. And I am going out to get some beer. (couldn't hurt)

Jagman60

OK guys, I have it running. First I found a weak ground going to the block, after I fixed that she started firing, I got the distributer roughly in the right place but she was missing really bad. Found one and two cylinders not firing. I pulled the injectors on those two and tested them outside the engine, they were bad. Have new injectors on order, I will let you know how it goes. Thanks to all for the help.

ChefYota4x4

iTrader: (5)

WHICH injectors weren't firing? I ask, because, well, I'm not CERTAIN I have this right.... But fairly sure that the No.10 and No.20 pins in the ECU, which EACH feed power to ONE wire that splits into a pair for injectors #1 and #3 and the other pair splits to feed injectors #2 and #4.... I'm just curious if you found one of those pairs not working.... If so, 2 things could have happened(or I could be totally wrong, lol)....

1. The pin on the ECU for No.10 or No.20 could have come out the back of the connector....

2. OR MORE OFTEN as is the case, 'the Y-Connection where the power wire splits into 2 for 2 injectors has busted loose on the solder or become so corroded that it's not often feeding those injectors. (When the motor comes out, the harness is usually twisted and such out of the way onto the fender and that wiring in there is VERY delicate in some cases.... even corroded or compromised in some way/or if it wasn't, it then would be, lol. Doesn't even OFTEN happen.. but it does happen.) That's what I'm not sure on....

.... GUYS, ...if one "Y" connection is compromised.... do ALL the injectors shut down? Cuz if that's the case, well, then this wouldn't apply to his situation. Just mentioning all this to keep Jagman on his toes and thinking before spending 200$ on reconditioned Injectors, ya know?

PS> If you have them out, why not send the other 2 off to be cleaned, even if they don't SEEM that bad? See, that's why this "2 injectors went out" thing is making me suspicious". lol

Jagman60

No, it was cylinders one and two. Also I tested those two injectors by powering them from the battery with a wire, one does not click and one makes a weak click. They sound different from the other two which do work.