Vitara 16v G16B 5 door JLX -94
the TPS must be calibrated. it's a tad tricky,, see my page on TPS cal? (it has the factory pages too)?/
http://www.fixkick.com/sensors/tests/TPS...html#MYWAY
if it dont close (idle switch), idle controls feature is disabled , if it opens late?, the ISC fights your right foot as you attempt to accelerate. (hesitations)
FailSafe.
http://www.fixkick.com/ECU/LimpHome/failsafe.html
Unplugging sensors, causes the ECU to drop to FailSafe mode, (rich,fuel, retarded spark timing , very ugly this mode is)
But ,most of these cars have 2 or more failures. and this can make fail safe , seem to make car run better. "relativity"
BTW, with TPS unplugged, the ECU uses, the MAF for the TPS, it takes MAF inputs and simulates a very very crude TPS sensor. this is how it works, and allows you to drive a car with dead sensors. see the CEL lamp blink on, that is the warning that the TPS is dead. (unplugged)
here is one case in point.
lets say, you have this failure (be it low fuel pressure?, or clogged injectors? or huge vacuum air leaks,?, the 16v MAF HATES AIR LEAKS )
RUNS LEAN.
the car has low power, because its lean all time time, (no scan tools for this car, so nobody notices the oxygen sensor stuck lean)
so you unplug the TPS, it goes to failsafe mode and goes richer , and like magic, gee this runs better.,
the classic,TWO WRONG ,Make a RIGHT. here . see that?
tool lean (failure ) + (too rich, failsafe) = is more close to normal... more close.
SCAN tool heaven.. (no more blind) way.
Now on my 1996, (or newer) we have a scan tool attached, I see CLOSED loop failed, hot idle, (BAD)
I replace my O2 sensor, and its still reading lean, no exhaust leaks.
i check fuel pressure and all sensors. all read correct. i find fuel pressure at 20 PSI, way too low. (oops wrong gas cap> missing vacuum breaker?)
or i find this huge vacuum leak in the intake plenum, oops all 4 injectors cushions are all cracked open, sucking air.
oops, the ISC air hose is cracked. (and lots more hoses, any and all MUST NOT SUCK AIR)
or like my 97, the main air pipe, on top the rear (unseen) mount broken, and the alum TUBE,had a huge hole in it, pinky sized.
in all cases closed loop failed, ISC had problems with idle (it can fix horrid lean) and the Long term fuel trim LTFT was stuck at +40% (adding tons of fuel and still cant get the 02 working right.)
the Typical, 1995 G16b , seen on the road.
has air leaks. all over, the plenum (MAF to intake valves)
the IAC my be stuck open (fast idle hot, or ISC hunting like mad because this IAC, NEVER closed at 150F.
the ISC may be sticking, most are. clean it.
A Bad TPS or not calibrated, or guessed at.?
Cracked #4 exhaust tube , sucking in fresh air, and now 02 sensor is reading way too lean forever.
Exhaust header (long tube) collector end, donut gasket, bad long long time ago. it's sucking fresh 20% oxygenated AIR all the time. O2 nuts again.
leaking or partial clogged injectors.
low fuel pressure. 36-43PSI running..is spec.. and regulates!. and FP regulator passes all tests in the FSM or my page.
http://www.fixkick.com/sensors/tests/FPress-reg1.html
the fuel pressure is not changing at idle. it must be steady, regulated. (if vacuum is steady the fuel pressure must be steady)
and must change pressure (drops) at wide open throttle. the REG is a 1:1 device, (fuel to vacuum)
1 PSI drop in plenum air pressure, nets a drop in fuel pressure of 1 psi. (or bar to bar pressure ,metric, or KPa to Kpa.)
This ECU can not see fuel pressure, so it must be correct at all times. (very unlike newer cars, with no loop for fuel lines)
if the FP regulator fails, say , stuck low, the ECU will UNDER INJECT FUEL. (failsafe, mode, may hide this)
this is the weakness, in this very old Suzuki system.
how is that? do ask questions.
this tool can help. (the only one on earth, (cept maybe a used $2000 tek1 scan tool 20 years old)
http://www.rhinopower.org/diag/sdl_if.html
the TPS must be calibrated. it's a tad tricky,, see my page on TPS cal? (it has the factory pages too)?/
http://www.fixkick.com/sensors/tests/TPS...html#MYWAY
if it dont close (idle switch), idle controls feature is disabled , if it opens late?, the ISC fights your right foot as you attempt to accelerate. (hesitations)
FailSafe.
http://www.fixkick.com/ECU/LimpHome/failsafe.html
Unplugging sensors, causes the ECU to drop to FailSafe mode, (rich,fuel, retarded spark timing , very ugly this mode is)
But ,most of these cars have 2 or more failures. and this can make fail safe , seem to make car run better. "relativity"
BTW, with TPS unplugged, the ECU uses, the MAF for the TPS, it takes MAF inputs and simulates a very very crude TPS sensor. this is how it works, and allows you to drive a car with dead sensors. see the CEL lamp blink on, that is the warning that the TPS is dead. (unplugged)
here is one case in point.
lets say, you have this failure (be it low fuel pressure?, or clogged injectors? or huge vacuum air leaks,?, the 16v MAF HATES AIR LEAKS )
RUNS LEAN.
the car has low power, because its lean all time time, (no scan tools for this car, so nobody notices the oxygen sensor stuck lean)
so you unplug the TPS, it goes to failsafe mode and goes richer , and like magic, gee this runs better.,
the classic,TWO WRONG ,Make a RIGHT. here . see that?
tool lean (failure ) + (too rich, failsafe) = is more close to normal... more close.
SCAN tool heaven.. (no more blind) way.
Now on my 1996, (or newer) we have a scan tool attached, I see CLOSED loop failed, hot idle, (BAD)
I replace my O2 sensor, and its still reading lean, no exhaust leaks.
i check fuel pressure and all sensors. all read correct. i find fuel pressure at 20 PSI, way too low. (oops wrong gas cap> missing vacuum breaker?)
or i find this huge vacuum leak in the intake plenum, oops all 4 injectors cushions are all cracked open, sucking air.
oops, the ISC air hose is cracked. (and lots more hoses, any and all MUST NOT SUCK AIR)
or like my 97, the main air pipe, on top the rear (unseen) mount broken, and the alum TUBE,had a huge hole in it, pinky sized.
in all cases closed loop failed, ISC had problems with idle (it can fix horrid lean) and the Long term fuel trim LTFT was stuck at +40% (adding tons of fuel and still cant get the 02 working right.)
the Typical, 1995 G16b , seen on the road.
has air leaks. all over, the plenum (MAF to intake valves)
the IAC my be stuck open (fast idle hot, or ISC hunting like mad because this IAC, NEVER closed at 150F.
the ISC may be sticking, most are. clean it.
A Bad TPS or not calibrated, or guessed at.?
Cracked #4 exhaust tube , sucking in fresh air, and now 02 sensor is reading way too lean forever.
Exhaust header (long tube) collector end, donut gasket, bad long long time ago. it's sucking fresh 20% oxygenated AIR all the time. O2 nuts again.
leaking or partial clogged injectors.
low fuel pressure. 36-43PSI running..is spec.. and regulates!. and FP regulator passes all tests in the FSM or my page.
http://www.fixkick.com/sensors/tests/FPress-reg1.html
the fuel pressure is not changing at idle. it must be steady, regulated. (if vacuum is steady the fuel pressure must be steady)
and must change pressure (drops) at wide open throttle. the REG is a 1:1 device, (fuel to vacuum)
1 PSI drop in plenum air pressure, nets a drop in fuel pressure of 1 psi. (or bar to bar pressure ,metric, or KPa to Kpa.)
This ECU can not see fuel pressure, so it must be correct at all times. (very unlike newer cars, with no loop for fuel lines)
if the FP regulator fails, say , stuck low, the ECU will UNDER INJECT FUEL. (failsafe, mode, may hide this)
this is the weakness, in this very old Suzuki system.
how is that? do ask questions.
this tool can help. (the only one on earth, (cept maybe a used $2000 tek1 scan tool 20 years old)
http://www.rhinopower.org/diag/sdl_if.html
http://www.fixkick.com