SOLVED!!! FJ62 dies while idling but restarts (1 Viewer)

[Fieldtester96]

So last night while waiting at a light my FJ62 suddenly died while idling in drive. I figured it was a fuel flow problem, because it would start up again then die. So today I went through the fuel lines and have no leaks. I decided to clean the charcoal canister and clean the tank valve on it. Once I got everything back together it runs significantly smoother now, but after idling under load for about 20 minutes it died again. Though it started back up with no problem and ran, but now when I have it in reverse with the break on it dies when I turn on the AC. I still think that maybe there is some air in the fuel lines but If its not that I'm not sure what else to check.

 

[Randy88FJ62]

You may have a vacuum leak. Check your intake hose from air cleaner box to the MAF. That caused me similar issues.

 

[Fieldtester96]

You may have a vacuum leak. Check your intake hose from air cleaner box to the MAF. That caused me similar issues.

I've had issues with that before too so I've replaced those hoses. When I had those problems I could run it when I had my foot on the gas. This problem seems to happen regardless of the how high the rpms are. But ill check again just to make sure

 

[Seth S]

does it stall while idling in neutral as well?

 

[Fieldtester96]

does it stall while idling in neutral as well?

Only after it has stalled while in drive. I haven't gotten it to stall in neutral yet so I'll just let it idle for a while and see what happens.

 

[Fieldtester96]

I'm thinking it may be a fuel pump problem, but I'm not sure because it does run.

 

[Seth S]

doesn't sound like a fuel pump problem to me. Sounds like your rpm isnt kicking up to compensate for the added load of turning the AC on and maybe your transmission isn't slipping at idle like it should which is causing the engine and brakes to fight and stall. Have you checked your trans fluid level? when did you last do a trans fluid and filter change?

 

[Fieldtester96]

doesn't sound like a fuel pump problem to me. Sounds like your rpm isnt kicking up to compensate for the added load of turning the AC on and maybe your transmission isn't slipping at idle like it should which is causing the engine and brakes to fight and stall. Have you checked your trans fluid level? when did you last do a trans fluid and filter change?

Its been about 5 years, I check the trans level about a month ago and it was good. Though I do know the rpm does kick up when I turn the AC on because the stalling isn't immediate. I'll check the trans level again, im probably due for a flush.

 

[Fieldtester96]

doesn't sound like a fuel pump problem to me. Sounds like your rpm isnt kicking up to compensate for the added load of turning the AC on and maybe your transmission isn't slipping at idle like it should which is causing the engine and brakes to fight and stall. Have you checked your trans fluid level? when did you last do a trans fluid and filter change?

The transmission fluid is good, it is a bit dark so I probably need to replace it but its definitely not low.

 

[Seth S]

It sounds like your trans is loading the engine...hopefuly a 62 trans expert kicks in some more info. @OSS ?

 

[Fieldtester96]

It sounds like your trans is loading the engine...hopefuly a 62 trans expert kicks in some more info. @OSS ?

I think you might be right, I had it idling fine for about 15 minutes. Put it into reverse and it stalled again.

 

[Fieldtester96]

After doing some more digging i decided to try and back off the fuel pressure regulator screw to see if that makes any difference. So far I have it idling in reverse to see if it dies again, so far its holding strong. Hopefully this will fix it and all I need to do is buy a new one just to be safe.

 

[Fieldtester96]

Okay so I had it idling in reverse for about 8 minutes, it was holding fine with no signs of stumbling. When I put on the ac compressor it stalled again. All I did was back out the screw on the fuel pressure regulator. So is it safe to say thats the problem? I'm gonna keep running it in reverse to see if it will die again without the AC pump on, but i just need some opinions to make sure I'm not making a correlation where one isn't.

Edit: I miss spoke, it was the fuel pressure dampener

Update: it just stalled after 10 minutes of idling in reverse. With the screw backed out when I start it back up after stalling it will run for a few seconds longer before it dies again.

 

[Fieldtester96]

Okay so now I can idle in reverse with the AC on as long as i turn it on before I put it into reverse. I'm thinking its a fuel pressure issue now. If I feel like if it was something with the transmission it wouldn't idle for so long in reverse.

Update: so after talking with a buddy who had a similar issue where when he was idling he would turn on the lights and it would die. I discovered that when in reverse my cruiser would die with the lights on. His problem turned out to be the alternator not giving enough amps. I would check that on mine but it seems I broke my multimeter so I have no way to see how much amps my alternator is putting out.

 

[Fieldtester96]

So my thought now is that the altenator is not pushing out enough amps. Which is causing the fuel pump to loose power, which is then causing fuel starvation in the engine causing it to die. I may be talking out of my ass, but logically it makes sense. I do know that crazy things happen when the altenator goes bad, so I'm gonna clean all the connections. If that doesn't work ill take it to get the alternator tested and go from there.

Feel free to tell me if I'm wrong on my assumptions.

 

[Fieldtester96]

Well im almost positive now that its the altenator. I can kill my car when its idling in park if I hold the window down button past when it's down. So I guess I'll just need to buy a new altenator and hope it fixes it

 

[Fieldtester96]

Okay last update, I got my hands on a multimeter and tested the voltage coming from the alternator. When In park with and without all accessories on it puts out 13.8v. When I put it into reverse and test it, it puts out 12.8 and then dies. So its definitely got to be the alternator, or something in my wiring system is really messed up.

So my plan now is to get a cheap reman alternator and see if that works. If it does ill get my Toyota alt rebuilt and keep the cheap alternator as a spare if this happens again.

 

[Seth S]

If you increase the rpms with all the accessories on does the voltage come up? I’m betting your alternator is fine and it’s just that at idle rpm it’s unable to output enough voltage to maintain the demand. Most alternators are not setup for max charging at idle. 12.8v is still charging.

I think your engine dies when you turn on electrical accessories because your alternator puts a load on the engine and either your efi or your ignition isn’t compensating for the increased load and it’s stalling.

 

[Fieldtester96]

If you increase the rpms with all the accessories on does the voltage come up? I’m betting your alternator is fine and it’s just that at idle rpm it’s unable to output enough voltage to maintain the demand. Most alternators are not setup for max charging at idle. 12.8v is still charging.

I think your engine dies when you turn on electrical accessories because your alternator puts a load on the engine and either your efi or your ignition isn’t compensating for the increased load and it’s stalling.

The problem is that the idle isn't lower than 800 when in drive while idling. I can run a load on it and be fine for a while but then It just cuts out randomly. It's like some turned the key off than the rpm dropping until it dies.

From what I read intermittent stalling is a symptom of a bad alternator, where only 2 of the 3 phases work. It will still charge but can't meet the amperage demand of the fuel injectors and stalls the car. Which matches my symptoms the best.

From what I understand extra load from lights and windows shouldn't cause the efi to bump up rpms because there is no extra load from the alt. The alt just has a constant torque needed and doesn't go up or down like when the AC kicks on. I may be wrong but even on carbed engines there is no compensator for loads being put on the Alt. Its the voltage regulator that tells the alt to put out more volts, because alts are supposed to keep around 14.2 volts no mater what rpm.

 

[Seth S]

Consider this: You don't need an alternator at all to run. If your battery is healthy your truck should be able to drive at least 50 miles without all the accessories on. My FJ60 recently drove over 100 miles and still started fine after I discovered the alternator wasn't charging as it should....even ended up driving about 25 miles with the headlights on and didn't stall.

So Alternator issues do cause problems but you have a battery for a reason. The battery is your power reservoir and it will run a car....even a modern car for quite a long time if the alternator has died. The only thing I think is happening with your alternator is that you are putting a load on it and a loaded alternator gets harder to turn and requires more horsepower. It sounds a lot like your fuel system isn't compensating for your various loads on the engine and thats causing a stall. This could be due to an unfound vacuum leak or a bad sensor, a dirty ground, or one of your main EFI components going bad...due to age, cleanliness, etc.

Alternators usually fail due to the brushes i the voltage regulator wearing out and or the contact surfaces the brushes riding on wearing. At which point the alternator stops charging or intermittently charges. I am sure that windings do fail now and then but I can honestly say that it the 27 years I have worked on and been around cars I have never seen an alternator fail due to a winding issue. Also if you are seeing 12.8v at idle with all the accessories on and over 13v with none on then you your alternator is charging fine. if you had a bad winding you wouldn't be seeing that.

"From what I understand extra load from lights and windows shouldn't cause the efi to bump up rpms because there is no extra load from the alt. The alt just has a constant torque needed and doesn't go up or down like when the AC kicks on. I may be wrong but even on carbed engines there is no compensator for loads being put on the Alt. Its the voltage regulator that tells the alt to put out more volts, because alts are supposed to keep around 14.2 volts no mater what rpm. "

I can assure you that when you put more load on the alternator the amount of torque needed to turn it does increase. A carbed engine will react to the increased load and the carb will do its best to maintain its idle speed but often the idle speed will in fact drop due to alternator loading if there is no other idle up switch. Alternators are not designed to output 14.2 volts regardless of the rpm. They are are designed to output max voltage at a certain rpm and if that rpm is say 2000 rpm you are not going to see 14v at idle