Truck won't start.. VAFM?
#1
Registered User
Thread Starter
Join Date: Jul 2009
Location: HI
Posts: 97
Likes: 0
Received 0 Likes
on
0 Posts
Truck won't start.. VAFM?
I have another thread going with a little information on this here:
https://www.yotatech.com/forums/f116...g-woes-201317/
but that one was originally for my timing problem and now that the problem has changed I'm going to make another thread for this one...
Problem is the 4runner won't start unless I have the VAFM unplugged (Also known as the VAF or MAF (Mass Air Flow/Volume Air Flow Meter)) With the sensor plugged in it cranks and almost starts, but never starts. With it unplugged it starts and runs for 7 seconds before it loses fuel pressure and dies. So I got another sensor and intake tube from a friend who's parting his truck out, but when I stuck that in it did the same thing. Anyone know what's going wrong? Thanks
I'll try n post pictures/videos when I get home
https://www.yotatech.com/forums/f116...g-woes-201317/
but that one was originally for my timing problem and now that the problem has changed I'm going to make another thread for this one...
Problem is the 4runner won't start unless I have the VAFM unplugged (Also known as the VAF or MAF (Mass Air Flow/Volume Air Flow Meter)) With the sensor plugged in it cranks and almost starts, but never starts. With it unplugged it starts and runs for 7 seconds before it loses fuel pressure and dies. So I got another sensor and intake tube from a friend who's parting his truck out, but when I stuck that in it did the same thing. Anyone know what's going wrong? Thanks
I'll try n post pictures/videos when I get home
#2
Registered User
Thread Starter
Join Date: Jul 2009
Location: HI
Posts: 97
Likes: 0
Received 0 Likes
on
0 Posts
With VAFM plugged in:
http://s14.photobucket.com/albums/a3...t=DSCF2922.flv
http://s14.photobucket.com/albums/a3...t=DSCF2922.flv
Last edited by k808soljah; 01-20-2010 at 04:42 PM.
#3
Registered User
Thread Starter
Join Date: Jul 2009
Location: HI
Posts: 97
Likes: 0
Received 0 Likes
on
0 Posts
VAFM unplugged:
http://s14.photobucket.com/albums/a3...t=DSCF2924.flv
http://s14.photobucket.com/albums/a3...t=DSCF2924.flv
#4
Registered User
Thread Starter
Join Date: Jul 2009
Location: HI
Posts: 97
Likes: 0
Received 0 Likes
on
0 Posts
VAFM unplugged:
http://s14.photobucket.com/albums/a3...t=DSCF2925.flv
http://s14.photobucket.com/albums/a3...t=DSCF2925.flv
Trending Topics
#8
Registered User
Thread Starter
Join Date: Jul 2009
Location: HI
Posts: 97
Likes: 0
Received 0 Likes
on
0 Posts
No, I haven't.. I don't have a scanner and I can't get it to autozone since it isn't running...
Since I wouldn't use it much, I'm not sure if a scanner would be worth buying.
I'll go out and try to pull them manually now, I just found a link on how to do that.... sorry I'm a newb
Since I wouldn't use it much, I'm not sure if a scanner would be worth buying.
I'll go out and try to pull them manually now, I just found a link on how to do that.... sorry I'm a newb
Last edited by k808soljah; 01-20-2010 at 10:27 PM.
#9
Registered User
Its definately not worth buying! Just use a paper clip to get codes. It's real simple. Open your little diagnostic box, it should be gray and say diagnostic on it.
Locate the places marked e1 and te1
put one end of the paper clip in each terminal
get a piece of paper and a pen
get in your truck and watch the check engine light
turn the key to the on position
count the flashes
it will have a set of flashes then a pause then more flashes
7 flashes pause 3 flashes = code 73
i'm gonna post all the codes here to make it easy for you to figure out what's going on
Locate the places marked e1 and te1
put one end of the paper clip in each terminal
get a piece of paper and a pen
get in your truck and watch the check engine light
turn the key to the on position
count the flashes
it will have a set of flashes then a pause then more flashes
7 flashes pause 3 flashes = code 73
i'm gonna post all the codes here to make it easy for you to figure out what's going on
#10
Registered User
By the way the, there's a diagram under the diagnostic box that tells you where e1 and te1 are
Last edited by DeathCougar; 01-20-2010 at 11:03 PM. Reason: OBD2 codes are 96+ only
#12
2 pause 2 is 22, and 2 pause 4 is 24.
Read this article: http://www.off-road.com/toyota/tech/codes/index.html
So, since you have an OBD1 system, codes read like this:
22:
WATER TEMPERATURE SENSOR SIGNAL--OPEN OR SHORT IN WATER TEMP. SENSOR SIGNAL
--WATER TEMPERATURE SENSOR CIRCUIT
--WATER TEMPERATURE SENSOR
--ECU
24:
INTAKE AIR TEMPERATURE SENSOR SIGNAL--OPEN OR SHORT IN INTAKE AIR TEMP. SIGNAL
--INTAKE AIR TEMPERATURE CIRCUIT
--INTAKE AIR TEMPERATURE SENSOR
--ECU
If the air flow meter isn't doing it, I would be looking at the cold start injector sensor, or the water temp switch which controls the IAC (intake air control) valve.
Read this article: http://www.off-road.com/toyota/tech/codes/index.html
So, since you have an OBD1 system, codes read like this:
22:
WATER TEMPERATURE SENSOR SIGNAL--OPEN OR SHORT IN WATER TEMP. SENSOR SIGNAL
--WATER TEMPERATURE SENSOR CIRCUIT
--WATER TEMPERATURE SENSOR
--ECU
24:
INTAKE AIR TEMPERATURE SENSOR SIGNAL--OPEN OR SHORT IN INTAKE AIR TEMP. SIGNAL
--INTAKE AIR TEMPERATURE CIRCUIT
--INTAKE AIR TEMPERATURE SENSOR
--ECU
If the air flow meter isn't doing it, I would be looking at the cold start injector sensor, or the water temp switch which controls the IAC (intake air control) valve.
#14
Registered User
--
11
LOSS OF POWER SUPPLY TO ECU
--IGNITION SWITCH/CIRCUIT
--MAIN RELAY/CIRCUIT
--ECU
6
12
RPM SIGNAL-NO SIGNAL TO ECU FROM DISTRIBUTOR ("Ne" OR "G") AFTER ENGINE HAS BEEN CRANKED
--DISTRIBUTOR/CIRCUIT
--STARTERSIGNAL CIRCUIT
--IGNITER/IGNITER CIRCUIT
--ECU
--
13
SAME AS ABOVE BUT AFTER ENGINE HAS RUN AT 1,000-1,500 RPM
--DISTRIBUTOR/DISTRIBUTOR CIRCUIT
--ECU
3
14
IGNITION SIGNAL--NO "IGF"SIGNAL TO ECU
--IGNITER/IGNITER CIRCUIT
--IGNITER AND IGNITION COIL/CIRCUIT
--ECU
5
21
OXYGEN SENSOR SIGNAL/OXYGEN SENSOR HEATER SIGNAL
OPEN OR SHORT IN OXYGEN SENSOR OR OXYGEN SENSOR SIGNAL
4
22
WATER TEMPERATURE SENSOR SIGNAL--OPEN OR SHORT IN WATER TEMP. SENSOR SIGNAL
--WATER TEMPERATURE SENSOR CIRCUIT
--WATER TEMPERATURE SENSOR
--ECU
8
24
INTAKE AIR TEMPERATURE SENSOR SIGNAL--OPEN OR SHORT IN INTAKE AIR TEMP. SIGNAL
--INTAKE AIR TEMPERATURE CIRCUIT
--INTAKE AIR TEMPERATURE SENSOR
--ECU
--
25
AIR/FUEL RATIO LEAN INDICATOR--LEAN SIGNAL SENT TO ECU FROM O2 SENSOR
--INJECTOR FAULT(S)
--FUEL PRESSURE
--OXYGEN SENSOR
--AIRFLOW METER OR MAP SENSOR
--IGNITION
--ECU
--
26
AIR/FUEL RATIO RICH INDICATOR
--SAME AS ABOVE
--COLD START INJECTOR
--
27
SUB-OXYGEN SENSOR CIRCUIT OR SUB-OXYGEN SENSOR HEATER CIRCUIT
--SUB OXYGEN SENSOR/HEATER/CIRCUIT
--ECU
--
28
No.2 OXYGEN SENSOR/OXYGEN SENSOR HEATER
--SAME AS CODE 21
2
31
MANIFOLD AND/OR AIRFLOW METER SENSOR SIGNAL CIRCUIT
--AIRFLOW METER/CIRCUIT
--MANIFOLD PRESSURE SENSOR/CIRCUIT
--ECU
--
32
AIRFLOW METER SIGNAL (VANE-TYPE)
--AIRFLOW METER./CIRCUIT
--ECU
14
34
TURBOCHARGER PRESSURE--ABNORMAL TURBOCHARGER PRESSURE
--TURBO CHARGER
--AIRFLOW METER/MANIFOLD/TURBOCHARGER PRESSURE SENSOR
--INTERCOOLER SYSTEM
--ECU
--
35
TURBOCHARGER PRESSURE SENSOR SIGNAL
--TURBOCHARGER PRESSURE SENSOR
--ECU
7
41
THROTTLE POSITION SENSOR SIGNAL--OPEN OR SHORT IN TPS SIGNAL
--TPS SENSOR
--TPS SIGNAL/CIRCUIT
--ECU
9
42
VEHICLE SPEED SENSOR SIGNAL CIRCUIT--NO SPD. SIGNAL FOR SEVERLA SECONDS
WHILE VEHICLE IS OPERATED UNDER HEAVY LOAD (TPS/MAP/AIR FLOW INPUTS)
--SPEED SENSOR/CIRCUIT
--ECU
10
43
STARTER SIGNAL--NO "STA" SIGNAL TO ECU UNTIL ENGINE SPEED EXCEEDS 800RPM
--IGNITION SWITCH/CIRCUIT
--ECU
11
51
SWITCH SIGNALS
IDL (tps) CONTACTS OFF, NEUTRAL START SWITCH OFF, A/C SWITCH "ON" SIGNAL TO ECU
WITH DIAGNOSTIC CHECK CONNECTOR SHORTED
--A/C SWITCH/CIRCUIT
--A/C AMPLIFIER
--TPS/CIRCUIT
--NEUTRAL START SWITCH/CIRCUIT
--ECU
12
52
KNOCK SENSOR SIGNAL--OPEN OR SHORT IN KNOCK SENSOR SIGNAL
--KNOCK SENSOR/CIRCUIT
ECU
13
53
KNOCK CONTROL SIGNAL IN ECU
--ECU
--
71
EGR VALVE MALFUNCTION--EXHAUST GAS TEMPEATURE BELOW SPEC. FOR EGR CONTROL
--EGR SYSTEM
--EGR GAS TEMPERATURE SENSOR/CIRCUIT
- -
72
AIR CONDITIONER COMPRESSOR RELAY/RELAY SIGNAL
--A/C COMPRESSOR RELAY/CIRCUIT
--ECU
11
LOSS OF POWER SUPPLY TO ECU
--IGNITION SWITCH/CIRCUIT
--MAIN RELAY/CIRCUIT
--ECU
6
12
RPM SIGNAL-NO SIGNAL TO ECU FROM DISTRIBUTOR ("Ne" OR "G") AFTER ENGINE HAS BEEN CRANKED
--DISTRIBUTOR/CIRCUIT
--STARTERSIGNAL CIRCUIT
--IGNITER/IGNITER CIRCUIT
--ECU
--
13
SAME AS ABOVE BUT AFTER ENGINE HAS RUN AT 1,000-1,500 RPM
--DISTRIBUTOR/DISTRIBUTOR CIRCUIT
--ECU
3
14
IGNITION SIGNAL--NO "IGF"SIGNAL TO ECU
--IGNITER/IGNITER CIRCUIT
--IGNITER AND IGNITION COIL/CIRCUIT
--ECU
5
21
OXYGEN SENSOR SIGNAL/OXYGEN SENSOR HEATER SIGNAL
OPEN OR SHORT IN OXYGEN SENSOR OR OXYGEN SENSOR SIGNAL
4
22
WATER TEMPERATURE SENSOR SIGNAL--OPEN OR SHORT IN WATER TEMP. SENSOR SIGNAL
--WATER TEMPERATURE SENSOR CIRCUIT
--WATER TEMPERATURE SENSOR
--ECU
8
24
INTAKE AIR TEMPERATURE SENSOR SIGNAL--OPEN OR SHORT IN INTAKE AIR TEMP. SIGNAL
--INTAKE AIR TEMPERATURE CIRCUIT
--INTAKE AIR TEMPERATURE SENSOR
--ECU
--
25
AIR/FUEL RATIO LEAN INDICATOR--LEAN SIGNAL SENT TO ECU FROM O2 SENSOR
--INJECTOR FAULT(S)
--FUEL PRESSURE
--OXYGEN SENSOR
--AIRFLOW METER OR MAP SENSOR
--IGNITION
--ECU
--
26
AIR/FUEL RATIO RICH INDICATOR
--SAME AS ABOVE
--COLD START INJECTOR
--
27
SUB-OXYGEN SENSOR CIRCUIT OR SUB-OXYGEN SENSOR HEATER CIRCUIT
--SUB OXYGEN SENSOR/HEATER/CIRCUIT
--ECU
--
28
No.2 OXYGEN SENSOR/OXYGEN SENSOR HEATER
--SAME AS CODE 21
2
31
MANIFOLD AND/OR AIRFLOW METER SENSOR SIGNAL CIRCUIT
--AIRFLOW METER/CIRCUIT
--MANIFOLD PRESSURE SENSOR/CIRCUIT
--ECU
--
32
AIRFLOW METER SIGNAL (VANE-TYPE)
--AIRFLOW METER./CIRCUIT
--ECU
14
34
TURBOCHARGER PRESSURE--ABNORMAL TURBOCHARGER PRESSURE
--TURBO CHARGER
--AIRFLOW METER/MANIFOLD/TURBOCHARGER PRESSURE SENSOR
--INTERCOOLER SYSTEM
--ECU
--
35
TURBOCHARGER PRESSURE SENSOR SIGNAL
--TURBOCHARGER PRESSURE SENSOR
--ECU
7
41
THROTTLE POSITION SENSOR SIGNAL--OPEN OR SHORT IN TPS SIGNAL
--TPS SENSOR
--TPS SIGNAL/CIRCUIT
--ECU
9
42
VEHICLE SPEED SENSOR SIGNAL CIRCUIT--NO SPD. SIGNAL FOR SEVERLA SECONDS
WHILE VEHICLE IS OPERATED UNDER HEAVY LOAD (TPS/MAP/AIR FLOW INPUTS)
--SPEED SENSOR/CIRCUIT
--ECU
10
43
STARTER SIGNAL--NO "STA" SIGNAL TO ECU UNTIL ENGINE SPEED EXCEEDS 800RPM
--IGNITION SWITCH/CIRCUIT
--ECU
11
51
SWITCH SIGNALS
IDL (tps) CONTACTS OFF, NEUTRAL START SWITCH OFF, A/C SWITCH "ON" SIGNAL TO ECU
WITH DIAGNOSTIC CHECK CONNECTOR SHORTED
--A/C SWITCH/CIRCUIT
--A/C AMPLIFIER
--TPS/CIRCUIT
--NEUTRAL START SWITCH/CIRCUIT
--ECU
12
52
KNOCK SENSOR SIGNAL--OPEN OR SHORT IN KNOCK SENSOR SIGNAL
--KNOCK SENSOR/CIRCUIT
ECU
13
53
KNOCK CONTROL SIGNAL IN ECU
--ECU
--
71
EGR VALVE MALFUNCTION--EXHAUST GAS TEMPEATURE BELOW SPEC. FOR EGR CONTROL
--EGR SYSTEM
--EGR GAS TEMPERATURE SENSOR/CIRCUIT
- -
72
AIR CONDITIONER COMPRESSOR RELAY/RELAY SIGNAL
--A/C COMPRESSOR RELAY/CIRCUIT
--ECU
#16
Registered User
Thread Starter
Join Date: Jul 2009
Location: HI
Posts: 97
Likes: 0
Received 0 Likes
on
0 Posts
#17
Registered User
22=water temp sensor - behind the intake, the closest plug to the drivers side, not to be confused with the cheaper "sender". About $30-40 bucks.
24=intake air temp sensor. It's built into your VAFM, and would naturally throw a code if you try to start it unplugged. Plug the VAFM back in, and clear your codes, try to start it again and then read the codes again. If it's still throwing a "24", then you have to replace the VAFM.
The cold start injector is on the passenger side of the intake with a gas line running to it. You can ubolt it off the intake, and then wrap it or jar it and watch to see if it squirts while you are cranking. There wasn't a code about that, though.
24=intake air temp sensor. It's built into your VAFM, and would naturally throw a code if you try to start it unplugged. Plug the VAFM back in, and clear your codes, try to start it again and then read the codes again. If it's still throwing a "24", then you have to replace the VAFM.
The cold start injector is on the passenger side of the intake with a gas line running to it. You can ubolt it off the intake, and then wrap it or jar it and watch to see if it squirts while you are cranking. There wasn't a code about that, though.
Last edited by DJ99; 01-21-2010 at 05:51 AM.
#18
Registered User
Thread Starter
Join Date: Jul 2009
Location: HI
Posts: 97
Likes: 0
Received 0 Likes
on
0 Posts
ECT/engine coolant temp sensor = water temp sensor, correct? Here's the fsm page for the ECT: http://personal.utulsa.edu/~nathan-b...98engineco.pdf Do you have a picture of the sensor so I know for sure which one to check w/the ohmmeter?
And if the I get code 24 with both of the VAFM's I have then they're both bad? Thanks
And if the I get code 24 with both of the VAFM's I have then they're both bad? Thanks
#19
Registered User
I have no picture of the coolant temp sensor. It's the closest one to the driver side in the little water manifold on the back side of the intake.
You can do a simple ohm measurement on the intake temp sensor. It's also in the FSM. If it's good, then it's the wires between there and the ECM.
You can do a simple ohm measurement on the intake temp sensor. It's also in the FSM. If it's good, then it's the wires between there and the ECM.
#20
Registered User
Thread Starter
Join Date: Jul 2009
Location: HI
Posts: 97
Likes: 0
Received 0 Likes
on
0 Posts
Got an ohmmeter from a friend so I'll be checking the resistance this afternoon. I don't know how to read this chart though: http://personal.utulsa.edu/~nathan-b...98engineco.pdf