Solved: Slow start (Battery was the problem)

[djambazoff]

Hello 4runner-mates,

Has anyone dealt with a slow start?
SOLVED: Bad battery ( 1 year old)

 

[kennythewelder]

There os some much other garbage on vehicles these days who knows, but how fast does it spin over? Is this the same speed all the way through the starting cycle? Next question, have you checked the fuel pressure with a gauge. The battery need to be checked with a battery load tester. Almost any auto parts store will have a load tester, and a fuel pressure test kit that you can rent. It also could be a security issue with the BCM, or ECM whatever one the security system is in.

 

[djambazoff]

There os some much other garbage on vehicles these days who knows, but how fast does it spin over? Is this the same speed all the way through the starting cycle? Next question, have you checked the fuel pressure with a gauge. The battery need to be checked with a battery load tester. Almost any auto parts store will have a load tester, and a fuel pressure test kit that you can rent. It also could be a security issue with the BCM, or ECM whatever one the security system is in.

* The spin speed seems the same, but once It gets into the firing stage, it starts "coughing slowly". Probably the sound is similar to the sound made when not enough gasoline is reaching to the system.
* I will have to check the fuel pressure with a gauge, but still I thought that if I wait total of 30 secs (3 x10 secs ) with ignition on, the fuel pressure would be loaded.
* The battery is 1 year old (Costco) and I did try turning ON in parallel AC, windows heaters, and all the lights - the battery voltage did NOT move from 10.8 at the time of starting.
* If it is a security related issue, then I wonder whether I can turn off the security component. (But if it was a security related, it would do it every-time the car is locked/unlocked. In my case, it happens only when the car is left for few hours parked OR each morning at first start)

 

[kennythewelder]

From what you descrive, it sounds like its starving for fuel. IDK what the fuel pressure is at prestart, and once the engine is running. I do know this however week fuel pressure will make a vehicle hard to start. Fuel pumps get old and lose there ability to put out the correct fuel pressure. A low voltage condition can also cause low fuel pressure. The fuel pump cycles for about 2 seconds with the key on, prestart. This gives enough fuel pressure to start the engine as long as everything is as it should be. I hope this gives you a little insight to how the system works. Without running test, it is just to hard to say, its this or its that.

 

[kennythewelder]

You may or may not know this, but the starter is tied into the BCM. So when you turn the key, the BCM is what sends a signal to the starter and starts the engine. Once the engine starts, the BCM tell the starter that the engine is started and to turns off its power. What those paramators are IDK. I also have a 2004 4 runner. The BCM, and ECM communiate with each other during the starting process.

 

[djambazoff]

You may or may not know this, but the starter is tied into the BCM. So when you turn the key, the BCM is what sends a signal to the starter and starts the engine. Once the engine starts, the BCM tell the starter that the engine is started and to turns off its power. What those paramators are IDK. I also have a 2004 4 runner. The BCM, and ECM communiate with each other during the starting process.

I wasn't familiar with that. But yes, the process flow is quite complex, so seems like hundreds of potential root problems exists.
One thing I remembered is that the previous owner(I'm the second one) changed the water pump at about 60K (Now 125K). I still have a very very little coolant leak, which I sometimes feel(smell) when I open the hood. Why I'm saying that: It is possible the coolant to start leaking thru the spark location (a mechanic proved that on a 2004 4runner V6, in a youtube video), and that would also cause a misfire at the starting engine point.

Thanks for sharing all that info. I will start with
* a fuel pressure test,
* then do a coolant pressure test ( which might open more questions if it fails)
* then change the starter ( just to exclude improper communication between BCM & ECM)
* if all the above doesn't help in any way, will just wait until I got some kind of error code signal.( currently I have none)

 

[kennythewelder]

A blown head gasket is the most likely cause of coolant in the cylinder. Not to say that this is your issue. If you pull the spark plugs and look at them, and you have coolant leaking into any cylinder, then that plug will be very clean as the coolant washes away any deposits. There are a ton of charts on reading your spark plugs out there. This can give you insight in to what you engine is doing and why you have a miss fire.

 

[69FJ-2.4LTRTDIESEL]

When did you last change the fuel filter and have you tested the holding pressure of the fuel line from the tank to the engine? Had a fuel line that was dry-rotted/cracked that would let the fuel drain back to the tank after sitting a while. The fuel pressure check is where I would start as previously recommended. Have you tested the coil on plug packs & the wiring for grounding?

 

[djambazoff]

When did you last change the fuel filter and have you tested the holding pressure of the fuel line from the tank to the engine? Had a fuel line that was dry-rotted/cracked that would let the fuel drain back to the tank after sitting a while. The fuel pressure check is where I would start as previously recommended. Have you tested the coil on plug packs & the wiring for grounding?

* Nope, I haven't done the pressure test yet - this is the next step. ( together with testing the coil on plug packs & the wiring for grounding)
* As far as I know, the fuel filter is enclosed with the pump in the tank, so not really serviceable.

I just did the battery test yesterday, on a 1.5 years old battery(24F size), and the report showed bad battery. For a moment, I thought I got it solved, but then this morning same issue with the brand new battery

 

[69FJ-2.4LTRTDIESEL]

Yes it is in the tank and polymer tanks don't have the rust/sludge problems the old tanks did. My thinking was your statement that after sitting for a few hours or overnight the hard start problem occurs. "If" there is debris in the filter it would settle to the bottom of the filter and when you try to start it would rise to plug/restrict the flow. I would want to know the volume (GPM) it puts out on the first start and on the after it starts mode. The fuel stations in many locations receive bulk fuel and if the station is the last on the delivery list or their tanks are sub par you get trash/water/sludge etc. which stays in the filter. Not saying it is but for me I'd like to know before I go deep into the system. Pressure test tells you how much pressure but nothing about volume, just MHO.

 

[djambazoff]

Yes it is in the tank and polymer tanks don't have the rust/sludge problems the old tanks did. My thinking was your statement that after sitting for a few hours or overnight the hard start problem occurs. "If" there is debris in the filter it would settle to the bottom of the filter and when you try to start it would rise to plug/restrict the flow. I would want to know the volume (GPM) it puts out on the first start and on the after it starts mode. The fuel stations in many locations receive bulk fuel and if the station is the last on the delivery list or their tanks are sub par you get trash/water/sludge etc. which stays in the filter. Not saying it is but for me I'd like to know before I go deep into the system. Pressure test tells you how much pressure but nothing about volume, just MHO.

Hm, that's very probable. Now I wonder how I can check the GPM fuel it delivers. Would toyata's techstream catch such a reading?

 

[69FJ-2.4LTRTDIESEL]

I am old school, I would take the line off at the fuel rail, add a piece of clear hose to the fuel pipe and put it into a glass jar (large small neck clear liquor/vodka bottle) turn on the key, note the flow, then I'd then try to cold start and see what amount it put out in say 15 seconds. Put it back together and get it started and functioning correctly. Stop the engine and perform the same test. Should be pretty evident if it delivers twice the amount of fuel with a warm engine. Be mindful it is gas & flammable so get help to do the start tests so you can control & monitor in real time. Just me, but I'm sure there is a piece of test equipment out there too.

 

[Bradley40504]

when you say slow, Im imagining the motor turns over very slowly like a weak battery? or do you mean its cranking but takes a long time to start? to me I call it cranking when you turn the key to start and the engine is turned by the starter, right? so that sound before it starts is cranking. if it cranks and takes long to start instead of 2 seconds? the options are gas, spark or engine damage. thats it right? so since it runs fine when hot, the engine is likely not damaged. how do the plugs look? are they the right heat range? here, you'd have to remove each plug and set it on some table thing in order so you can see if one cylinder is different? I had a problem like this and it was the fuel pump, but I spent weeks thinking oh, its some computer signal or some sensor or the most complex thing? Nope, it was the fuel pump. If your starter cranks the engine at normal speed, it should be fine. Id just replace the fuel pump. Its a miserable job and expensive but you could have this problem like me in some part of Los Angeles and not be able to start and be stuck at a McDonalds all night sleeping in the truck and people walk up and look in the window? Some gal did that and I sat up, scaring her she screamed and ran and said theres a guy in there! I said a little prayer, tried it and it started and was able to drive away like 2am. you dont want that. Id suggest doing the pump while you can, its a once every 10 years kind of thing. Fuel pressure is very high, so it will spray out, but not be enough to run right. Another time in LA I had my Chevy, flat tire, no jack and a Ford tire tool thats 13/16 and GM is 3/4. had to smash and bend a couple pennies on some rocks to fit in there and loosen/replace lug nuts. had a block of wood, was able to push it on the axle housing then back up and it lifted that wheel off the ground, all late at night. took probably an hour. It makes one think to the maintenance in your house

 

[69FJ-2.4LTRTDIESEL]

Did you get it figured out?

 

[djambazoff]

Did you get it figured out?

I went to a shop, they checked the fuel pump and also told me that the initial pressure was fine.
Then we went to a snow park with the kid, and I decided to do another test: The car stayed for about 3 hours within 25 F', I started the engine and waited about 2 minutes, observing the temperature meter not to start getting up. Then I turned it off, waited 10 secs and started again. The issue was still there, probably a bit less noticeable. Left the engine running for about 5 minutes, and the temperature went half to the middle, then I turned OFF. In about 15 secs started again - no issue at all, like new.
In short, the issue seems to be temperature dependent. ( I'm driving with 10w30, but don't think the oil is that thick in order to cause such a slow start)
Let me know if something else comes to your mind which would be temp sensitive.

 

[69FJ-2.4LTRTDIESEL]

The only thing that comes to my mind is maybe water in the tank?? I've been told that if you pour rubbing alcohol (I think that was the type alcohol) it will get the water out, I never tried it by they make off the shelf things that do also. I wish all the tanks had drain plugs so you could drain to find out, water is heavier than gas so the gas sits on top. When I fly part of the walk around inspection of the plane I drain fluid from each tank to see if water is present, why not cars too?? Electronics side I don't have a clue but I'm gonna research
& if I see something I'll get back. Let us know if you find the problem. Good luck.

 

[jimmyjim]

so, how old is the fuel filler cap? now i have a completely different truck. 85 2wd 22r carb. but all these trucks have a vacume vapor release prevention gas tank and fuel system. if the seal on the gas cap is old and allows vacume to leak down then that can make the engine hard to start. i replaced mine, along with the fuel filter, so i dont know which fixed it, but it starts easy now. my son swears by seafoam, it cleans the lines and the injectors. other issues i have had include the ignition timing wires getting brittle and cracking inside the insulation where you cant see it. the engine timing chain streched so ignition timing is a little spotty. a faulty electronic ignition module.
in short, all that everybody dreads is this kind of problem. do check timing, and spark. and let us know what you figure out.