Cold Hard start
11-24-2008, 08:39 AM
#1
Contributing Member
Thread Starter
iTrader: (2)
Join Date: Jun 2006
Location: Miami, FL
Posts: 2,312
Cold Hard start
do you guys think having a bad o2 sensor or removing the o2 sensor would make my SR have a cols start problem..
i cant think of anything else right now it runs perfect even have very good air fuel ratio it only goes a little rich after i let go of the gas but thats expected because of my blow off valve.
but yea the colder it is the harder it is to start when the engine is warm or has been running already it will start right up. but i just hope its not an 02 problem right im hard on money cant spend money on a new 02 sensor...
but the only reason i wouldnt think its an 02 sensor is cause my KA had a bad o2 and it always started fine
i cant think of anything else right now it runs perfect even have very good air fuel ratio it only goes a little rich after i let go of the gas but thats expected because of my blow off valve.
but yea the colder it is the harder it is to start when the engine is warm or has been running already it will start right up. but i just hope its not an 02 problem right im hard on money cant spend money on a new 02 sensor...
but the only reason i wouldnt think its an 02 sensor is cause my KA had a bad o2 and it always started fine
11-25-2008, 08:38 AM
#6
no that doesn't sound normal at all. when i temporally removed the canister from my car it took about 3 or 4 seconds for it to start and that was a long time to me. other than the usual lose or dirty connections on the alternator, battery, and ignition components there is one thing that i can think of.
your battery may not have enough amps to start cold but after the engine starts and the alternator takes over it may retain enough amps to start initially after being turned off but not after it sits for a while. that or a leaky injector, now i'm just guessing thought.
your battery may not have enough amps to start cold but after the engine starts and the alternator takes over it may retain enough amps to start initially after being turned off but not after it sits for a while. that or a leaky injector, now i'm just guessing thought.
11-25-2008, 09:45 AM
#7
Contributing Member
Thread Starter
iTrader: (2)
Join Date: Jun 2006
Location: Miami, FL
Posts: 2,312
nah i know its not the battery cause this battery never had a problem starting the SR. and i mean hard start i have to crank 30-40 seconds somtimes or more. could be leaky injector but wouldnt that make the car run funny?
but now that you said charcoal canister i never blocked off the line from the canister to the hard line its just open it may be that i will block it off now and how that goes
but now that you said charcoal canister i never blocked off the line from the canister to the hard line its just open it may be that i will block it off now and how that goes
11-25-2008, 11:34 AM
#8
yeah a leaky injector could cause it to run funny if it's staying open at start up. after than you may not notice it. it's happened to me on two separate occasions with two different cars so it's possible. i'm still leaning toward the charcoal canister though.
11-27-2008, 10:48 AM
#9
I have the exact same problem with my SR.
I don't know what it is either.
Takes about 20 secs to start, havent drained a battery though.
I have to hit the gas to get it to start.
Starts right up when the engine is hot.
I don't think its the injectors, because i've had leaky injectors in my KA.
I don't have a carbon canister either.
I don't know what it is either.
Takes about 20 secs to start, havent drained a battery though.
I have to hit the gas to get it to start.
Starts right up when the engine is hot.
I don't think its the injectors, because i've had leaky injectors in my KA.
I don't have a carbon canister either.
11-27-2008, 06:33 PM
#10
Registered User
Join Date: Jun 2008
Location: Ky
Posts: 33
Check ECT(engine coolant temperature) sensors under cold starts the PCM uses this as the high authority sensor until O2 is at operating temp then it goes into closed loop. Until it goes into closed loop you PCM is reading this and using short term fuel trim to decide how much fuel to add also called open loop you will run rich at this time.
There are some other possible causes I'll check back
There are some other possible causes I'll check back
11-28-2008, 09:14 AM
#12
Check ECT(engine coolant temperature) sensors under cold starts the PCM uses this as the high authority sensor until O2 is at operating temp then it goes into closed loop. Until it goes into closed loop you PCM is reading this and using short term fuel trim to decide how much fuel to add also called open loop you will run rich at this time.
There are some other possible causes I'll check back
There are some other possible causes I'll check back
you may have something there but i'm not sure this holds true with heated o2 sensors.
11-28-2008, 04:30 PM
#13
Registered User
Join Date: Jun 2008
Location: Ky
Posts: 33
Even with the heated O2 the vehicle will still run in open loop until the PCM reads the voltage signal usually 2 cycles of rich and then lean. O2 sensor works off 1 volt switching. Above .800v you have a rich mixture and below .200v you have a lean mixture. Let me know if you have any other problems.
11-28-2008, 05:46 PM
#14
Contributing Member
Thread Starter
iTrader: (2)
Join Date: Jun 2006
Location: Miami, FL
Posts: 2,312
well only reason i dont think its the o2 sensor is cause my obd2 KA had a bad o2 sensor and never had a problem starting it just ran rich. now my SR has a problem starting yet has and almost perfect AFR (yes i have a wideband) it only goes a little rich when i let off the gas but thats to be expected because of my Blow off valve.
anyway not sure how to test the ECU temp sensor a new one isnt bad though $30 can just get one from an auto parts store the 91-94 s13 KA temp sensors work.
anyway not sure how to test the ECU temp sensor a new one isnt bad though $30 can just get one from an auto parts store the 91-94 s13 KA temp sensors work.
11-28-2008, 09:20 PM
#15
Registered User
Join Date: Jun 2008
Location: Ky
Posts: 33
The richness after throttle is not due to blow off valve. Any vehicle will run rich after throttle NA and Forced Induction, the throttle plate is closed not allowing air to pass by. At the same time The PCM has not changed the pulse width of the injector. Soon as O2 sees the rich mixture PCM reads that and changes the pulse width. Therefore after throttle you should see a rich signal, what your wide band is showing you.
To test you ECT sensor with it still in the vehicle you measure voltage with a DVOM ( Digital volt ohms meter). Get some T-pins and back probe the sensor plug and. With you meter lead connected to reference wire on Ka's it's light orange( don't remember what the Sr color is). and your negative lead to good ground source. Start your vehicle and as you vehicle warms up and gets up to operating temp the voltage should increase cause resistance decreases as temp goes up. If the meter you would be using is not auto ranging, set to 20vDC
The sensor is not a pricey one but to rule it out I would check it first
To test you ECT sensor with it still in the vehicle you measure voltage with a DVOM ( Digital volt ohms meter). Get some T-pins and back probe the sensor plug and. With you meter lead connected to reference wire on Ka's it's light orange( don't remember what the Sr color is). and your negative lead to good ground source. Start your vehicle and as you vehicle warms up and gets up to operating temp the voltage should increase cause resistance decreases as temp goes up. If the meter you would be using is not auto ranging, set to 20vDC
The sensor is not a pricey one but to rule it out I would check it first