Grrr hang in there. I have been through similar problems only to find chaffing on CAN wires.
LC not starting month 2 :-( Saga continues. EFI fuse?
- Thread starter jcmiro
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I am hoping it’s not something like that which is so hard to locate.
Wife’s key and remote start didn’t Work, but do help rule out immobilizer
Last couple times it’s been cranking and not catching as quickly. . .
maf cleaning or new sensor
Crank position sensor
Fuel pump
Fuel relay
Fuel Ecu
Are likely targets
I’m gonna get some throttle body cleaner or starting fluid and see if it will run on an alternate fuel source.
Your symptoms sounds like a fueling issue as a result of some sensor erroneous reading, rather than a hard sensor failure. The fact that it starts yet dies, without error codes, tells me this. This alone rules out quite a bit of electronics stuff as it wouldn't start otherwise if there were critical hard wire faults like a crank position sensor.
Sorry if my earlier post looks like a complete stab in the dark. I do have some experience debugging ECM's, having installed standalone and piggybacks back int he day.
Trust me on pulling the MAF. It's one of the primary diagnostic steps to disable the closed loop fueling strategy. The ECM will default to open loop baseline maps and it will not hurt a thing, other than to set an actual MAF CEL as it doesn't have readings for intake air temperature (IAT) and mass airflow (MAF). Both easily cleared by pulling the batt again, or clearing with a tool.
Give that a try and report back.
Sorry if my earlier post looks like a complete stab in the dark. I do have some experience debugging ECM's, having installed standalone and piggybacks back int he day.
Trust me on pulling the MAF. It's one of the primary diagnostic steps to disable the closed loop fueling strategy. The ECM will default to open loop baseline maps and it will not hurt a thing, other than to set an actual MAF CEL as it doesn't have readings for intake air temperature (IAT) and mass airflow (MAF). Both easily cleared by pulling the batt again, or clearing with a tool.
Give that a try and report back.
I've unplugged the MAF sensor.
I now have a VSC and 4LO flashing, which are likely indicative of expected codes from having the MAF unplugged.
Same behavior as before. Crank, catch, die.
I'm booting my ancient Techstream laptop now and should have the codes pulled shortly.
I now have a VSC and 4LO flashing, which are likely indicative of expected codes from having the MAF unplugged.
Same behavior as before. Crank, catch, die.
I'm booting my ancient Techstream laptop now and should have the codes pulled shortly.
I pulled and checked any fuse related to Ignition and EFI. I also swapped the EFI relay with another (the rear tow), just in case.
I also tried overamp fuses in the 20A and 25A EFI spots.
Here are all the codes:
Engine and ECT
P0102 Current and Pending and History
P0113 Current and Pending and History
ABS/VSC/TRAC
C1201 Current
C1268 Current
TPMS
C2144 History
AIR Con
B1421 Current (solar sensor - it was dark)
B1424 Current (solar sensor - it was dark)
Main Body
B1206 History
B2321 History
AES
B2412 History
B2413 History
Intuitive P/A
C1AED History
SRS Airbag
B1856 History
I think the only relevant are P0102 and P0113. These are also the only ones that show up in both the Advanced and Generic sections (Techstream vs OBD2).
P0102 - Mass Airflow Sensor Low (It is unplugged, so yeah)
P0113 - Intake Air temperature High (also due to MAF unplugged)
Still no start condition.
Left to check:
Top likelies:
Fuel pump
Fuel relay
Fuel Ecu
maf cleaning or new sensor (have unplugged sensor and still no start). The sensor is missed by the ECU, so I think the sensor is probably ok, but I'll probably get an aftermarket one anyway just in case, they're $20.
Crank position sensor (probably not this per @TeCKis300
Thanks again for the replies
I also tried overamp fuses in the 20A and 25A EFI spots.
Here are all the codes:
Engine and ECT
P0102 Current and Pending and History
P0113 Current and Pending and History
ABS/VSC/TRAC
C1201 Current
C1268 Current
TPMS
C2144 History
AIR Con
B1421 Current (solar sensor - it was dark)
B1424 Current (solar sensor - it was dark)
Main Body
B1206 History
B2321 History
AES
B2412 History
B2413 History
Intuitive P/A
C1AED History
SRS Airbag
B1856 History
I think the only relevant are P0102 and P0113. These are also the only ones that show up in both the Advanced and Generic sections (Techstream vs OBD2).
P0102 - Mass Airflow Sensor Low (It is unplugged, so yeah)
P0113 - Intake Air temperature High (also due to MAF unplugged)
Still no start condition.
Left to check:
Top likelies:
Fuel pump
Fuel Ecu
maf cleaning or new sensor (have unplugged sensor and still no start). The sensor is missed by the ECU, so I think the sensor is probably ok, but I'll probably get an aftermarket one anyway just in case, they're $20.
Crank position sensor (probably not this per @TeCKis300
Thanks again for the replies
As a side note, when you find yourself pulling fuses, just replace them with LED fuses. Since I had a couple of gremlin problem years ago, I now prophylactically replace the fuses in every vehicle.
Useful. Even though pulling the MAF didn't result in any difference, we can now at least isolate that the problem is generally not on the intake track/intake sensor side (except throttle body?). Don't bother replacing the MAF. That is not it. Aftermarket ones are junk. Nor would I bother replacing fuses unless one is actually blown. It's just throwing money way as they either work or they don't.
Yes, I would expect those CEL codes once pulling the MAF. I would reset the ECU and start fresh after putting the MAF back.
Does throttling the car on startup make any change in keeping the car running? Or no difference?
For an engine to run, it's air/fuel/spark.
Air - we isolated some if it via the MAF. There's still others though. Have you serviced your car recently for whatever reason? Any chance you introduced a vacuum leak post throttle body? PCV valve? Can you pinch the hose going to the PCV valve to isolate if there is excess air coming from there for whatever reason? Check any other hoses post TB, to make sure there's not leaks.
Spark, since it starts but dies, I would suspect this is fine. It's possible there's a problem here but unlikely.
Fueling. Still suspect. But at least we know it's not the ECU trimming fuel wrong for whatever reason as we pulled the MAF, and you have reset the ECU to eliminate trims. Did you say you did some debugging here by changing the pump already? May need to test the pressure but that requires some specialized tools.
Yes, I would expect those CEL codes once pulling the MAF. I would reset the ECU and start fresh after putting the MAF back.
Does throttling the car on startup make any change in keeping the car running? Or no difference?
For an engine to run, it's air/fuel/spark.
Air - we isolated some if it via the MAF. There's still others though. Have you serviced your car recently for whatever reason? Any chance you introduced a vacuum leak post throttle body? PCV valve? Can you pinch the hose going to the PCV valve to isolate if there is excess air coming from there for whatever reason? Check any other hoses post TB, to make sure there's not leaks.
Spark, since it starts but dies, I would suspect this is fine. It's possible there's a problem here but unlikely.
Fueling. Still suspect. But at least we know it's not the ECU trimming fuel wrong for whatever reason as we pulled the MAF, and you have reset the ECU to eliminate trims. Did you say you did some debugging here by changing the pump already? May need to test the pressure but that requires some specialized tools.
Thanks @TeCKis300. I'll look into the air sources, but visual inspection today didn't reveal anything.
I have not replaced the fuel pump. I do intend to get some starter fluid tonight and try that tomorrow as an alternate fuel source.
The car will not stay running no matter how much accelerator pumping is done. On a 'cold' start (24 hours since last try), it'll catch, run up to 1500 rpm, then die. From then on out it cranks, fires, then dies.
No servicing of any kind recently. I did replace the front diff oil a few weeks ago. I haven't done anything new under the hood since the OBA install, which is a couple months ago.
It is confounding, as the rig drove perfect right into my usual parking spot. And was a non-start the next morning. No warning from anything - no fuel cut type issues as I'd expect from a clogged fuel filter (i know there isn't one, but still) or a pump going sideways.
Agree most likely at this point is fuel pump. I also watched a youtube video on a tundra last night which had fuel pump ecu as a cause.
I have not replaced the fuel pump. I do intend to get some starter fluid tonight and try that tomorrow as an alternate fuel source.
The car will not stay running no matter how much accelerator pumping is done. On a 'cold' start (24 hours since last try), it'll catch, run up to 1500 rpm, then die. From then on out it cranks, fires, then dies.
No servicing of any kind recently. I did replace the front diff oil a few weeks ago. I haven't done anything new under the hood since the OBA install, which is a couple months ago.
It is confounding, as the rig drove perfect right into my usual parking spot. And was a non-start the next morning. No warning from anything - no fuel cut type issues as I'd expect from a clogged fuel filter (i know there isn't one, but still) or a pump going sideways.
Agree most likely at this point is fuel pump. I also watched a youtube video on a tundra last night which had fuel pump ecu as a cause.
I'll add the tank is near the reserve light, my range is currently 3 miles. That should leave about 4 gallons in the tank at this point.
I didn't suggest replacing fuses with same regular fuses. That would be stupid. But indicator fuses show the blown fuse with a glance. Very helpful.
Carry on!
Carry on!
@Sedalia , I was more commenting on the overamp fuses.
@grinchy , do you have a propane torch? It can be used in place of the starter fuel. Just open the airbox and put the unlit torch input there. Std caution applies in risk of an intake backfire.
Curious about the low fuel level. While I generally trust the gauge, it may very well be just out of fuel?? Are you parked on a slope?
@grinchy , do you have a propane torch? It can be used in place of the starter fuel. Just open the airbox and put the unlit torch input there. Std caution applies in risk of an intake backfire.
Curious about the low fuel level. While I generally trust the gauge, it may very well be just out of fuel?? Are you parked on a slope?
I have a box of mini fuses (non LED) to use. I wasn't replacing, just pulling, verifying continuity, and putting them back. I did swap in 'bigger' fuses to EFI (that is from the 100 forum as a potential fix). This didn't change anything. At the moment the original fuses are back.
I did find one that a 15 was in instead of a 10. I did put a 10 in that spot. It wasn't an EFI fuse . . .
I am also 'missing' a couple of fuses labeled R/R AC. One mini size and one of the square 25A. Not sure if this is because I don't have RR AC, or perhaps previous owner had an issue and just pulled those fuses (rather than do whatever was necessary to fix). It isn't related to this issue. I didn't put fuses in for this, that is a fix for a later time.
I did find one that a 15 was in instead of a 10. I did put a 10 in that spot. It wasn't an EFI fuse . . .
I am also 'missing' a couple of fuses labeled R/R AC. One mini size and one of the square 25A. Not sure if this is because I don't have RR AC, or perhaps previous owner had an issue and just pulled those fuses (rather than do whatever was necessary to fix). It isn't related to this issue. I didn't put fuses in for this, that is a fix for a later time.
Not parked on a slope. Have considered adding a couple gallons. Note I don't have a 'low fuel' warning atm.
You never want to put a larger amperage fuse in place of an original fuse. Especially in the case of a short to ground. That is a good way of smoking a wire harness or ECU. They are designed for that purpose.
Here is the wire diagram for your cruiser. Was it the efi main fuse or efi2 fuse that is blowing?
Here is the wire diagram for your cruiser. Was it the efi main fuse or efi2 fuse that is blowing?
@Crab Sack
I have discovered no 'burnt' fuses. I initially (and still kinda) think it's an immobilizer issue. In the 100 forum (and on a couple 200s), using a 'larger' EFI fuse (or a short, like a paperclip) has resolved longterm the immobilizer, which cuts off the fuel pump. The core issue on the 100 is that fuse box had a manufacturing quirk that led to loose or missing connections. The real fix was a new fusebox.
Also one of the other members mentioned I should check all the fuses. So I did that today (I pulled all the EFI related fuses and relays and verified they were fine).
I agree that using an incorrect fuse size should only be for troubleshooting, as it's just a bandaid in best of times, and can lead to real harm in some situations.
I have discovered no 'burnt' fuses. I initially (and still kinda) think it's an immobilizer issue. In the 100 forum (and on a couple 200s), using a 'larger' EFI fuse (or a short, like a paperclip) has resolved longterm the immobilizer, which cuts off the fuel pump. The core issue on the 100 is that fuse box had a manufacturing quirk that led to loose or missing connections. The real fix was a new fusebox.
Also one of the other members mentioned I should check all the fuses. So I did that today (I pulled all the EFI related fuses and relays and verified they were fine).
I agree that using an incorrect fuse size should only be for troubleshooting, as it's just a bandaid in best of times, and can lead to real harm in some situations.
Gotcha, an immobilizer issue would throw codes that I do not see, also it would start briefly and then shut off. I would crack a fuel line to see if you have fuel pressure while cranking it over. If no, then I would suggest going after checking power and ground to the fuel pump. I have seen failures of fuel pumps, Fuel pump ECUs and also Engine ECUs not sending a fuel signal to the fuel pump ecu. Let me know what you find
Fuel pump is around $300. Still probably less than a bad ecu
