Stalls When cold
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From: North Gower. Ontario
Maybe we went to deep in this rabbit hole.
the problem is that the car stalls only when the engine temp is cold and then drives perfect.
so either i let it warm up on idle or I try to drive a couple of times until it runs and that's it.
the problem is that the car stalls only when the engine temp is cold and then drives perfect.
so either i let it warm up on idle or I try to drive a couple of times until it runs and that's it.
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No, it shouldn't stall when cold...period !!...now how long or what temp does it have to be before it conks out ??...did you ever look at ECT or IAT data PIDS under the OBD2 part of your scan tool and not going to GM, etc... ??...under OBD2 the PCM will not report a "substituted value" like I mentioned...it will show the temp the engine computer is seeing....and the engine has to sit overnight before looking at these temps...not a few hours.
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No, it shouldn't stall when cold...period !!...now how long or what temp does it have to be before it conks out ??...did you ever look at ECT or IAT data PIDS under the OBD2 part of your scan tool and not going to GM, etc... ??...under OBD2 the PCM will not report a "substituted value" like I mentioned...it will show the temp the engine computer is seeing....and the engine has to sit overnight before looking at these temps...not a few hours.
2. all the tests / pid checks were made under obdII mode ever since you showed me how.
3. the last ECT and IAT tests were in obdII mode and after sitting overnight (this morning)
the only faulty element was the o2 sensor that "came back to life", maybe because I disconnected and reconnected the boosters vacuum hose or maybe because the temp at the sensors housing was warm enough.
maybe we should wait for it cool down and see live data on obdII mode of temp and fuel?
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1. have to let the car cool down to check temp but it takes a few minutes to warm up before I can drive it.
2. all the tests / pid checks were made under obdII mode ever since you showed me how.
3. the last ECT and IAT tests were in obdII mode and after sitting overnight (this morning)
the only faulty element was the o2 sensor that "came back to life", maybe because I disconnected and reconnected the boosters vacuum hose or maybe because the temp at the sensors housing was warm enough.
maybe we should wait for it cool down and see live data on obdII mode of temp and fuel?
2. all the tests / pid checks were made under obdII mode ever since you showed me how.
3. the last ECT and IAT tests were in obdII mode and after sitting overnight (this morning)
the only faulty element was the o2 sensor that "came back to life", maybe because I disconnected and reconnected the boosters vacuum hose or maybe because the temp at the sensors housing was warm enough.
maybe we should wait for it cool down and see live data on obdII mode of temp and fuel?
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From: North Gower. Ontario
Really only needed to check the ECT and IAT in OBD2 with the key on and engine off...you can check your data on the "factory" side once you are ready to check again...what if you engage the E-brake and let the clutch out giving it just a little gas...will it stall ??...try to put a little load on the engine !!
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From: North Gower. Ontario
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From: Cape Coral, Florida
This may just be a column lock issue but you are not getting any messages associated with that…it’s strange it only happens with the engine cold…my issue happened with engine at operating temp and not…if that’s the case you can order an LMC5 from Amazon…I’ve never researched if there are more parameters needed other than the engine quitting at 2 MPH…wondering if you were on a hill and let it roll above 2 MPH if it would stall ??…mine would stall basically when my clutch was let out but I did receive the “pull key…” message.
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From: North Gower. Ontario
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From: Cape Coral, Florida
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From: North Gower. Ontario
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From: Cape Coral, Florida
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From: North Gower. Ontario
We have a crazy thunder storm here and tomorrow starts an even crazier work week...
I`ll have to put a pause on it..
Thank you for all the help. it is just amazing how much knowledge and will to help.
I`ll update next week when I can keep trying out all the tests (I`m having fun here)
I`ll have to put a pause on it..
Thank you for all the help. it is just amazing how much knowledge and will to help.
I`ll update next week when I can keep trying out all the tests (I`m having fun here)
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From: North Gower. Ontario
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Well it sounds like something electrical…if it’s fine when it’s warmed maybe an electrical connector is making better contact (expands when heated)…it may be a crank sensor or it’s connection or maybe the fuse box…I would scope a few things to see what’s dropping out…if this all happened after replacing the ignition switch I’d readdress that…I’d pull the switch and inspect all the contacts…the circuit that supplies power to the PCM (where the crank sensor gets its power) may be dropping out when it stalls…if you can monitor the fuse voltage somehow either at the PCM (back probing the wire) or at the fuse (if you have some very thin copper wire you can wrap it around the blade and reinstall the fuse)…you can try PCM fuse 16 because that circuit is always powered with the ignition key in ON or START.
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Joined: May 2021
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From: North Gower. Ontario
Well it sounds like something electrical…if it’s fine when it’s warmed maybe an electrical connector is making better contact (expands when heated)…it may be a crank sensor or it’s connection or maybe the fuse box…I would scope a few things to see what’s dropping out…if this all happened after replacing the ignition switch I’d readdress that…I’d pull the switch and inspect all the contacts…the circuit that supplies power to the PCM (where the crank sensor gets its power) may be dropping out when it stalls…if you can monitor the fuse voltage somehow either at the PCM (back probing the wire) or at the fuse (if you have some very thin copper wire you can wrap it around the blade and reinstall the fuse)…you can try PCM fuse 16 because that circuit is always powered with the ignition key in ON or START.
just thinking of taking apart all the panels to get to the switch again. omg..
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Joined: May 2021
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From: North Gower. Ontario
Well it sounds like something electrical…if it’s fine when it’s warmed maybe an electrical connector is making better contact (expands when heated)…it may be a crank sensor or it’s connection or maybe the fuse box…I would scope a few things to see what’s dropping out…if this all happened after replacing the ignition switch I’d readdress that…I’d pull the switch and inspect all the contacts…the circuit that supplies power to the PCM (where the crank sensor gets its power) may be dropping out when it stalls…if you can monitor the fuse voltage somehow either at the PCM (back probing the wire) or at the fuse (if you have some very thin copper wire you can wrap it around the blade and reinstall the fuse)…you can try PCM fuse 16 because that circuit is always powered with the ignition key in ON or START.
