FJ62 first would not run when hot. Now runs when cold, but dies when put in gear then will not start without ALOT of cranking. (1 Viewer)

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This car has 299k, but it had the engine replaced at some point, so don't know the engine mileage. Whoever replaced it did a crappy job.
About 1 -2 years ago, when it would get hot it would not idle - you would have to rev it to keep it going. This slowly got worse, and I really didn't want to go through the FSM to figure it out.
It got bad enough, it would not idle at any temp, but it would start OK and drive OK. I figured it was time to go through the FSM.
Found both temp sensors broken/not working. Replaced the one above the thermostat and the one directly below.
Then tried to drive it. Worked while it was cold, but once it warmed up, it would run about 2500, then die when put in gear. The first couple times, I WOT and it sortof ran. As long as it was in gear and foot on the throttle it mostly ran...The third time, it died and would not start. Got towed to a parking lot where I futzed with it, and finally got it to start.

Strong smell of gas, and once it started, it seemed like the plugs were pretty fouled. Finally got it home and am now going through the FSM more througly.

Found the hose from the cleaner to the throttle body had a massive hole, so I wrapped all that tight with bicycle innertube and taped the outside with electrical. No codes other than the ECU had the power removed (no CEL, short TE1/E1 have two slow blinks every 5 sec or so).

I thought the coil might be bad. Measures .5/11K - normal.
Put new Denso wires and plugs (gapped at .031).

Put a new fuel filter in not long ago. Filter might have 5k on it max.

I had voltage for the VT1/VT2, but no voltage swings, (sensor voltage .38V steady) so figure the O2 sensors might be bad. I disconnected both sensors, and it still has the same symptom:

It will start from cold and idle (idle is high, but I futzed with the idle speed setting early on), but when put in gear, dies and won't start after. When it is in this condition, the coil is sparking like it should and all the cylinders show lights from the timing light like the coil/igniter are doing their job.

I pulled a plug while it was in this state, and the plug looked black, but dry, which almost seems like it's not firing the injectors or pressure is low or something, but I don't know why it would run fine at 4000 if it was fuel supply issues. I will check the fuel pressure once I get a banjo fitting.

It is almost like the ECU looses it's mind and lights up the coil at the wrong time or something. I can crank it on a full battery and eventually it will start again.

If you pull the O2 sensors, I would think the ECU would think they were bad and just go into limp mode, but maybe it thinks there is no gas and just fills the cylinders with gas, but why does it idle OK?

Also, without it in gear, I can punch it and it sounds like it's missing/runs like crap until about 4K, at which point is smooths out and runs like it should.

One other data point. It wouldn't start after cranking for a while, so I pulled the bajo bolt on the fuel rail to measure it to put a longer one with another banjo for a gauge, forgot about it, went out and it started right up, fuel squirting everywhere. put the bolt back in, started, idled, put it in gear drove it back a few feet, left it in gear and revved it until, put it in neutral..did that a couple times, then wham, dies. I have a timing light hooked up with the trigger on so I can see the coil. Never misses I can tell. Won't start. I swear this is going to drive me crazy.

Pulled the bolt again, tried to start, no fuel spewing, so I finally have a place to look.

Anybody have any ideas? I'm not too far away from figuring out how to put a carburetor on this car.
 
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I’d go through and base line everything before going crazy.

You mentioned wires and plugs did you do cap and rotor also?

I’d take the time to do a valve clearance check and adjust.

Then check the timing

Do a compression test.

Look for missing or broken vacuum lines and holes in the intake hose.

Replace the air filter

Measure your fuel pressure

Once you got the basics covered then start going through the FSM diagnosis for ignition and efi
 

ChaserFJ60

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Found the hose from the cleaner to the throttle body had a massive hole, so I wrapped all that tight with bicycle innertube and taped the outside with electrical. No codes other than the ECU had the power removed (no CEL, short TE1/E1 have two slow blinks every 5 sec or so).
A hole after the MAF can cause all sorts of strange problems, Made my engine knock. I would revisit that and be 100% certain that the hose is air tight. Any vacuum or air line cracked will cause an issue.
 
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Although I agree I should set the valve clearance, it's not why it's doing it's weirdness. I've done the spray starter fluid on the vacuum lines with zero response. Air filter is not an issue since it's not closed. Cap was in sad shape - so worn it had worn the plastic off the dist side where the carbon brush is. I replaced it with a good used one but have new parts coming in. Also waiting on parts to measure the fuel pressure. I HAVE been going through the FSM. All weekend long, in fact.

I can't believe it ran at all with the intake hose in such sad shape. I have a silicon part coming I'm hoping will fit. The trouble with this vehicle is that I had bought it for parts, and when I found out there was nothing wrong with it other than a bad water pump, I replaced the pump and never went through it like I usually would.

I either have a bad fuel pump or one of those relays is jacked. I bet good money on a relay going on the blink. I had the same thing happen with my 78 Corona - fuel pump was fine but the relay would disconnect while I was driving or other random times. I jumpered it and has been driving fine ever since.
 
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Although I agree I should set the valve clearance, it's not why it's doing it's weirdness. I've done the spray starter fluid on the vacuum lines with zero response. Air filter is not an issue since it's not closed. Cap was in sad shape - so worn it had worn the plastic off the dist side where the carbon brush is. I replaced it with a good used one but have new parts coming in. Also waiting on parts to measure the fuel pressure. I HAVE been going through the FSM. All weekend long, in fact.

I can't believe it ran at all with the intake hose in such sad shape. I have a silicon part coming I'm hoping will fit. The trouble with this vehicle is that I had bought it for parts, and when I found out there was nothing wrong with it other than a bad water pump, I replaced the pump and never went through it like I usually would.

I either have a bad fuel pump or one of those relays is jacked. I bet good money on a relay going on the blink. I had the same thing happen with my 78 Corona - fuel pump was fine but the relay would disconnect while I was driving or other random times. I jumpered it and has been driving fine ever since.
Did ya figure it out?
 
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No, still haven't figured it out. It is still sitting in my driveway looking sad. The update is that I pulled both O2 sensors, then I put a timing light on the coil and put the fuel pressure on the rail, and I have both spark and pressure when it all goes south. Still have spark/pressure, but the stupid thing will not run.

I will pull the TPS off and check it - it isn't loose, but if you had something similar it is worth eliminating. When you say loose, what do you mean?

I just bought a 1uZ-FE motor to turbo for use in my dream sleeper --- a 1978 toyota corona with a CD00A behind it and a FJ40 rear axle, and the relavant piece of that info is that in a very short order I got the $170 Speeduino ECU to run that motor, and since the diagnostics from the 3FE ECU are nil in this case, I'm thinking a speeduino conversion will at least tell me what is going on. I have new O2 sensors, but the darn thing should run without them (very rich, yes), but it should run.

I do know I can convert this thing to a carburetor. The dist makes it easy. I just want to pull my hair out.
 
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@Seth S posted a good list of things to check, including the timing, did you do that? What is it set to? Everything else is a waste of time if you haven't first confirmed the timing is correct. Maybe you did this - but you haven't specifically mentioned it in this thread. All you said is basically "the timing light fires", which isn't really confirming the timing is correct.

I also had a high idle issue, here is my post on that: FJ62 engine miss at idle (3fe) where to start? - https://forum.ih8mud.com/threads/fj62-engine-miss-at-idle-3fe-where-to-start.983467/#post-12047670
 
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I pulled out the ECU and connecting wires, nothing is pinched or looks damanged. I plugged it in, it starts right up. It idles right where it should, I can punch it and it revs like it should. Seemed to run fine in the driveway and I was thinking, maybe it was just oxidation on a connector. Drove it up a really steep subdivision hill next to me - it's running great. I can punch it and it responds like it should. I get to the top and just before the end, it dies. Same crap as before. I use the momentum to turn around and coast back down, then start while coasting in gear. It catches, but it will not run below about 2500. Above that RPM it runs fine. I still have the fuel pressure gauge on, and it's running 38-40, even while this is happening.

So at least I can confirm it runs fine while cold, and since all this started after fixing the broken temp sensor, I'm going to pull all temp related sensing (all 5 of them) and disable/disconnect. The sensor that had failed failed at 56 ohms which would have placed the temp of the engine around 1500 degrees:) I think operating range is around 1400 ohms, not 56. But I can sure play with that while it's running.

BTW, this is all with the O2 sensors still disconnected, since according to the FSM they are not functional anyway. It's killin' me. And no, I have not checked the timing because I cannot see the mark back in that dark cave. I did the jumper and tried. I think there is grease or something on the mark, but it is always hard to see that mark with these engines. It doesn't help that it's at a perfect distance to not see well without glassed and not well with glasses either.

I'm 99% sure it is not the timing, since it runs fine until it doesn't. The valve clearance will help it run better, but valve clearance will not stop a running engine. I know the clearance is not bad on the loose side because you can hear it when they are. If they are tight, you don't hear that little clack. I do have three FJ60s that I've set clearance on multiple times as well as a 78 Corona with the 20R - all have a similar cam. If they are tight, it will lose power and do other bad things, but it will not keep it from running if it is already running.

@toy_tek, your description just reminded me of some other maintenance I need to do as well.
 
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So I finally disconnected the temperature sensor and it now runs. I suspect the ECU is bad, but since I've discovered Speeduinos, I will likely just convert. There are too many parts on this vehicle that are no longer made related to the ECU.
 

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