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Thread ID: 117652	2011-04-27 21:53:00	Motor question	beetle (243)	PC World Chat

Post ID	Timestamp	Content	User
1197832	2011-04-28 16:12:00	the iron no longer looks to be the nice symetrical shape its supposed to be. but it did fly sorta well considering its shape and everything......... Did I not see a Linux screensaver like this once?	SurferJoe46 (51)
1197833	2011-04-28 22:38:00	Dunno... the "After Dark" screensavers from Berkeley Systems had flying toasters... There might be a clone for Linux that uses clothes irons instead...	Agent_24 (57)
1197834	2011-04-29 06:02:00	It gets mind boggling after a while. Got it, Thanks SJ. It is mind boggling. I read in Nissan Forums, some US drivers, "remap"/download codes for their ECU's. I guess a quick fix or more personalized driving parameters.	kahawai chaser (3545)
1197835	2011-04-29 10:47:00	I always thought that if a warning light showed, you took the bulb out which cured the problem.	gradebdan (2186)
1197836	2011-04-30 13:09:00	The fuel tank has an aneroid sensor in it (piezzo device, really and to save inventory, most manufacturers just uses another BARO sensor here) that when the ECM doesn't see a small vacuum created in the tank after a set time factor, it will light the CEL . It really has nothing to do with the fuel pressure after the pump - which is in the tank . There are times when the engine will be running with less than a full control situation from the ECM . It can default to a 'limp-home' condition in the worst of cases - but that's so rare that we never really see that in the shops . Limp-home is a condition where the engine cannot maintain certain prescribed parameters of it's emission related design and it will/will not allow some or all of the following: 1) 2nd gear (forward) only with normal Park, Reverse and Neutral . But there are lots more Neutrals to limit road speed and force the operator to seek qualified repairs . This is most times a transmission situation though . 2) Loss of full advance in the ignition to retard the timing and the operator knows that the engine is running badly and seeks help . 3) Modified fuel injection event or ON FUEL millisecond trim command time to diminish performance to cause the driver to seek professional help . NOTE::: this INJECTOR TRIM is expressed in milliseconds and actually a HIGHER number indicates that the ECM is attempting to lower the total fuel expressed by the injector to lean-out the cylinder, whereas a shorter TRIM value turns the fuel UP or increases the time the injector is ON and admitting fuel into the cylinder . Digitally expressed TRIM is a negative value, not a positive one . These OF COURSE are hard-failures and a bright red CEL will be lit or have been lit for an extended period of time . Fuel mileage and performance is severely curtailed to get the operator's attention . Don't ignore the little red light . In some owner's cases there should be a little hammer that comes out of the head rest to get the driver's attention . SOME vehicles use an ORANGE or AMBER CEL to tell the driver that a SOFT failure is happening and should be investigate ASAP - but if it turns RED it is always BAD! I've seen black tape covering a persistent CEL that the driver didn't want to notice or didn't care or just thought it was some sort of gimmick . BELIEVE THE RED CEL LIGHT - IT'S TALKING TO YOU!!! IF there is a problem - even a mundane one like a spark plug that is not firing correctly - the ECM will know (trust me - it does) and the CEL will come on and stay on until the condition is rectified . Remember that any difficulty that the ECM sensors see and report are all emission related really - and things like a bad plug wire (or in the case of Coil-On-Plug or COP ignition that the whole individual coil is bad) or low fuel pressure or a defective catalytic convertor or a failure to attain normal operating temperatures after a designated period of time or even a mechanical condition such as a burnt valve, faulty injector or broken exhaust pipe before the cat - these will all trip the CEL and it will not go out until either: A) a scan tool is used to erase the fault code or B) in SOME cases the soft fault has rectified itself . Don't count on B (above) to work for you though - this is a rare situation and is usually reserved just for the fuel cap which is out of the explicit control of the ECM (dumb humans drive ECMs crazy) . The sensors are looking for values that affect their voltage - either in their ability to flow current through them eg: the MAF sensor, TPS,, CTS thermistors OR they are sending voltage that they themselves generate eg: piezzo devices in BARO or digital signals from assorted tone-wheels in the Cam Position Sensor (CMP) or the Crankshaft Position Sensor (CPS) or the Vehicle Speed Sensor (VSS) and even the tone wheel generators at each brake rotor/drum that tell the ECM and/or the TCM the actual RPM of each wheel . BTW: TCM = Transmission Control Module whereas ECM = Engine Control Module . There are also BCM and DCMs to consider, Body Control Modules and Driver's Control Modules - these latter ones are for zone HVAC and seat memories . radio station presets, even pedal heights and sensitivities . SIDEBAR::: GM had an original idea in their Climate Control System (CCS) that would not allow chilled air from the AC to blow from under the dash onto a driver's legs until the temperature could be controlled with sufficient engine heat in the cooling system to offset the extreme cold of chilled air . The reason? To keep women's legs from getting a cold shot of air up under their skirts until the temperature could actually be moderated by the Climate Control settings with heated air mixed into the cold . Modern ECMs have a 'learned response' to the driver whereas it can read the chip on the ignition key of a driver (some at a distance of over 30 feet away) and know the driving characteristics of that person and create a driver's profile to maximize what it deigns as a best-response to their driving style . But as another key chip was brought near the vehicle, it's digital code was read to reset the parameter to that driver, so two different drivers had their own personal driving profile memorized by the ECM and it can act accordingly, giving each driver what they want while driving the vehicle . Like I said - these are sometimes capable of pre-adjusting mirrors, interior temperatures, seat positions, aggressiveness of shifting in the transmission, engine performance parameters, resetting the radio or CD or MP3 playlist, vehicle overall ride height and whether 'Sport' or 'Boulevard' driving profiles were needed by that particular driver via their personal digital chip code . Kinda neat - huh? One more interesting point to consider::: In some vehicles - the individual spark plugs are also used as sensors too . Let me explain . AFTER the plug has been fired to ignite the fuel charge at the appropriate time, the ICM (Ignition Control Module) 'sees' the ion stream that still exists across the electrodes of the spark plug during the 'waste cycle' or when the exhaust valve is open and the spent gasses are going out through the open exhaust valve . IF this ion semi-conductive stream is weak and easily gets 'blown away' or sheared and therefor acts as a strong resistor to ion flow, or if it is very strong and passes an electrical charge readily to ground the ECM knows that this individual cylinder's fuel charge-to-air ratio is wrong and can correct the individual injector to compensate for whatever condition exists . It gets mind boggling after a while . . Yeah that's what happened to me, i have a 2004 Suzuki Grand Vitara, . 2 . 0 turbo Diesel . and one day the engine light came on, as i was driving to a friends place, well when i went to leave the engine light went off like normal, and for a couple weeks, it would randomly come on while driving, or not turn off once the car started, and then later it would turn off, then eventually it would stay on continuously . and also while driving it would randomly limit the revs so it wouldn't rev over 3000 RPM, so i would have to turn the car off then start it and it would be back to reving properly . so i thought it might have been the fuel filter, so i put a new one in, and it fixed the revving problem, but the light was still on . so i went and took it to a mechanic friend and sent it to get it plugged in to the Diagnostics machine, and it was a fuel sensor, that had been tripped, and didn't reset itself after i changed the filter, and they reset it, Problem fixed . Car electronics can be a wonderful thing, no more trying to guess where the problem is, just plug it in and the car will tell you, -) Amazing	stevensaaron (6348)
1197837	2011-04-30 14:27:00	Yeah that's what happened to me, i have a 2004 Suzuki Grand Vitara,. 2.0 turbo Diesel. and one day the engine light came on, as i was driving to a friends place, well when i went to leave the engine light went off like normal, and for a couple weeks, it would randomly come on while driving, or not turn off once the car started, and then later it would turn off, then eventually it would stay on continuously. and also while driving it would randomly limit the revs so it wouldn't rev over 3000 RPM, so i would have to turn the car off then start it and it would be back to reving properly. so i thought it might have been the fuel filter, so i put a new one in, and it fixed the revving problem, but the light was still on. so i went and took it to a mechanic friend and sent it to get it plugged in to the Diagnostics machine, and it was a fuel sensor, that had been tripped, and didn't reset itself after i changed the filter, and they reset it, Problem fixed. Car electronics can be a wonderful thing, no more trying to guess where the problem is, just plug it in and the car will tell you, -) Amazing The ECM just KNOWS! In what I call: 'The Punishment Factor' - some of the newer vehicles will make life so hard that you've GOT to get it scanned or you'll shoot it between the headlights. I started in the trade as alternators were making their presence felt and disk brakes were in their infancy. We figgured that they'd go back to the old ways when they found out they didn't work well - but we wuz wrong.	SurferJoe46 (51)
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