Lets talk tests

HiLife said:
Hate for your to give up on this. But man you do have a frustrating issue with this one.
Did you confirm that the FPR inside bellows is not ripped inside and siphoning raw fuel through the vacuum hose?
Ever got a chance to read the STFT and LTFT?
There was another member on here that had that fast clicking iac that you got early on, flooded condition and a hard start or bad no start.
I'm not saying that this is what your going through but, it is a good read and to learn from.
Click to expand...

Been busy with work and time hasn't been on my side.
Im going to check that FPR for sure today.
The fast clicking IAC was replaced with new and hasn't done that since.

It hasn't stalled since the cleaned injectors but check engine light keeps coming on with engine misfire codes. Multiple cylinders. Usually everyone of them.

It runs its just not reliable yet.

I did read the other thread. I would hate to think about replacing the ECU after all of this. Thats not usually part of maitence items I was prepared to replace.
 
19963.4lsr5 said:
You put all the vacuum lines back on for the IAC bypass? Or they didn’t crack or fall off?


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Click to expand...

So
They are all on but... I started removing all of the vac lines to inspect and found the one on top of the upper intake split.

Then found most are less than ideal. Time to replace them.
But what why the misfire in all cylinders?
Vac Leakes should cause lean condition which I can figure is the lines cracking.
 
Question is what are all of the different sizes for vac lines? Looks like I should replace them all to get everything back up in order.

The FPR looks look based off of no fuel in vac line

Fuel pressure is steady at 45-46 psi under idle.
 

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So I fixed the broken vac line.
Cleared the codes then tested once again. Pending codes of misfire 1-2-3-4-6

Would the crankshaft position sensor cause me issues but not throw a code for it ??

Misfires in most cylinders ?
 
sweet88gt said:
https://www.toyota-4runner.org/atta...182d1589500365-lets-talk-tests-a1_170551d-jpg

If anyone ever stumbles across the crazy thread this picture may help for vac lines. Look like Toyota part numbers for each.
Click to expand...


When I rebuilt the engine I ordered all new coolant lines to delete the aux heater. As well as the vacuum lines from the IAC to the two injector rail vacuum ports.

The 171 code is system too lean which explains your missfire code. If you are just checking the fuel pressure leading up to the regulator it still leaves the question of what is your fuel pressure at the injectors.

Either you got a vacuum leak or a sensor that helps controls fuel management is not imputing correct data to the ECU or something is up with the injectors you just put in.


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19963.4lsr5 said:
When I rebuilt the engine I ordered all new coolant lines to delete the aux heater. As well as the vacuum lines from the IAC to the two injector rail vacuum ports.

The 171 code is system too lean which explains your missfire code. If you are just checking the fuel pressure leading up to the regulator it still leaves the question of what is your fuel pressure at the injectors.

Either you got a vacuum leak or a sensor that helps controls fuel management is not imputing correct data to the ECU or something is up with the injectors you just put in.


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Click to expand...

Im not sure but since the injectors I have no stall which was the original problem. Im sure I could have fixed one issue and now chasing another.

That lean code has now disappeared and my guess is that vac line fixed that issue. It was split length ways and was audible. It actually kept getting worse. I probably broke it in the injector replacement procedure.
 
So Im not even sure Im doing the datalog thing correctly or if I even have the correct PIDs listed.
I have the dash command app for iPhone and the wifi deal under the dash.

I need to look at STFT bank 1
LTFT bank 1
O2 voltage bank 1
coolant temp
MAF
rpm

Anything else?
Ill be back it tomorrow
 
So looks like I have come to a dead end. Im about out of my area of expertise on this.

Need to find a mechanic that has a good scanner and who can figure it out.

If anyone has an input on that catalog deal Im all ears.
 
sweet88gt said:
So looks like I have come to a dead end. Im about out of my area of expertise on this.

Need to find a mechanic that has a good scanner and who can figure it out.

If anyone has an input on that catalog deal Im all ears.
Click to expand...

you have checked for a vacuum leak and found nothing correct - I have heard you can spray brake cleaner / other flammable aerosols around the vacuum lines to check for this. Perhaps the O2 sensors are bad ( I don't think they are terribly expensive or hard to replace. Have you changed out the fuel filter? Just swining in the dark.
 
Last edited:
From another thread where the fuel filter apparently fixed an idle issue. Probably won't help, but at this point, if I am not mistaken you have already checked: Plugs, Wires, TPS, IAC, Fuel Pressure, Fuel Injectors?, vacuum hoses, MAF. May be worth it to see if its one of these weird gremlins ( O2 sensor, fuel filter), before moving on to ECU stuff.

I understand this is an old thread but i figured for the benefit of the next person that is searching for a solution, I'd add my insights here.

I had done a valve cover gasket job and replaced the air boot due to a tear. While I had the throttle body off I cleaned it along with IACV. I replaced the PCV as well. When I got it back together, my idle was high. It's been that way for about a year. Usually when the truck would warm up after driving it around, the idle would return to the normal range. I tried resetting the ECU multiple times. I replaced the MAF. Cleaned the MAF later. Replaced the air K&N air filter. Removed the throttle body and IAC again. Everything looked good. I checked the vacuum hoses looking for leaks. Nothing there either.

Today, i installed a new fuel filter and VOILA! No more high idle. Note I didn't even remove the battery ground to do this. I just unplugged the connection to the fuel pump, ran the fuel line dry (wouldn't start actually) and replaced the filter. Happy to report no high idle. If the problem should return, I will report back.

Hope this helps someone down the road
Click to expand...
 
Your LTFT for bank 1 is all over the place. Anywhere from 3 to almost 20. That’s your missfire and P0171 codes.

You replaced the injectors correct? If so you may have gotten a bum set or they aren’t seated in the intake correctly.

Or there is a sensor not providing proper data to the ECU.


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So I let this thing sit and walked away from it to clear my mind.

Test drive again and now no misfire codes in the 30 min ride with about 10 miles of driving. Start and stop let it sit in parking lot and such.

So no misfire codes
Just the P0171
I haven't done anything to try to fix. My guess now is a vacuum leak since I have had the intake off a few times.
I have cleaned MAF so Im hoping that is good.

Ran well with no stall. Check engine light only came on right before I shut the engine off when I got home.
 
19963.4lsr5 said:
Your LTFT for bank 1 is all over the place. Anywhere from 3 to almost 20. That’s your missfire and P0171 codes.

You replaced the injectors correct? If so you may have gotten a bum set or they aren’t seated in the intake correctly.

Or there is a sensor not providing proper data to the ECU.


Sent from my iPhone using Tapatalk
Click to expand...

I had a set of injectors cleaned and installed them.
 
Gull81 said:
From another thread where the fuel filter apparently fixed an idle issue. Probably won't help, but at this point, if I am not mistaken you have already checked: Plugs, Wires, TPS, IAC, Fuel Pressure, Fuel Injectors?, vacuum hoses, MAF. May be worth it to see if its one of these weird gremlins ( O2 sensor, fuel filter), before moving on to ECU stuff.
Click to expand...

Fuel filter was the first step.
 
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