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car won't start Please HELP! any ideas will help
I had unfortunately been involved in an accident in the rear which isn't so bad bent the crash bar and where the trunk latch is but anyways there was a four inch section of wiring harness in the trunk that was pinched and worn through and making my brakes operate the stereo so I had patched that back together and meanwhile the car wasn't starting so I had hoped that this simple fix would fix the starting issue but in fact it didn't. so I got the codes checked and they came back as P2122 P2138 P1229 P0452 which all lead back to the throttle position sensor except for one for the catalytic converter. So I got a replacement from a parts car and that still didn't fix it I have also replaced the starter and battery with a higher cranking amperage I'm stumped and sick of throwing money at dead ends if anyone has any ideas they would be much appreciated.
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Is there gas in the car?
Is there spark? From reading your post you appear to have a lack of logical troubleshooting skills. Just throwing parts from a questionable vehicle and guessing is only going to make things worse. You never mention using a multi-meter or even having a OBDll reader. My advice Tow it to a dealer for a proper diagnosis Telcoman |
Originally Posted by telcoman
(Post 7130355)
Is there gas in the car?
Is there spark? From reading your post you appear to have a lack of logical troubleshooting skills. Just throwing parts from a questionable vehicle and guessing is only going to make things worse. You never mention using a multi-meter or even having a OBDll reader. My advice Tow it to a dealer for a proper diagnosis Telcoman In my post I said I have got the codes checked then listed them I have an obdII scanner and I have spark and I have gas |
Originally Posted by Conner Butler
(Post 7130358)
In my post I said I have got the codes checked then listed them I have an obdII scanner and I have spark and I have gas http://www.nicoclub.com/service-manu.../Sedan/2008/EC You never mentioned the year and model of your vehicle. See page EC-428 DTC No. Trouble diagnosis name DTC detecting condition Possible cause P2122 Accelerator pedal position sensor 1 circuit low input An excessively low voltage from the APP sensor 1 is sent to ECM. • Harness or connectors (APP sensor 1 circuit is open or shorted.) • Accelerator pedal position sensor (APP sensor 1) P2123 Accelerator pedal position sensor 1 circuit high input An excessively high voltage from the APP sensor 1 is sent to ECM. You may have a wiring harness issue? When first replaced the battery did the original starter crank the engine? When you removed the original starter did you ever test it by applying 12v to it? Did you ever perform a compression test? Did you ever test for fuel pump pressure? Telcoman |
Originally Posted by telcoman
(Post 7130360)
Have you followed the troubleshooting steps in the FSM?
http://www.nicoclub.com/service-manu.../Sedan/2008/EC You never mentioned the year and model of your vehicle. See page EC-428 DTC No. Trouble diagnosis name DTC detecting condition Possible cause P2122 Accelerator pedal position sensor 1 circuit low input An excessively low voltage from the APP sensor 1 is sent to ECM. • Harness or connectors (APP sensor 1 circuit is open or shorted.) • Accelerator pedal position sensor (APP sensor 1) P2123 Accelerator pedal position sensor 1 circuit high input An excessively high voltage from the APP sensor 1 is sent to ECM. You may have a wiring harness issue? When first replaced the battery did the original starter crank the engine? When you removed the original starter did you ever test it by applying 12v to it? Did you ever perform a compression test? Did you ever test for fuel pump pressure? Telcoman the original starter was compleletly fried from trying to start is to many times. I haven’t tried testing compression or the fuel pressure and I can take another look at the wiring harness in the trunk again the car is a 2005 g35x Sedan. |
How exactly did you check for spark, you SAW IT WITH YOUR OWN EYES yes? How much gas is physically in the tank, not just "how much gas does the instrument cluster say" since the gauge is notorious for failing.
P2122, P2138 is not the throttle position sensor it's the physical gas pedal (Accelerator Pedal Position, which is actually a switch, no linkage). P1229 just means that part of the accelerator sensor circuit (pedal, tb, throttle position, etc) is shorted out, usually a pinched wire. Probably related to the APP position switch. P0425 is the EVAP controller (located in the rear of the vehicle near the gas cap area) which is likely part of that damaged wiring that was *fixed*. I would definitely re-inspect the wiring that you patched, if it wasn't SOLDERED and HEAT SHRINKED then either get the tools to do a proper repair or have someone else do it, you will absolutely have problems again in the future if you just used some crappy double-end butt splices and *** wrap. As for actual repair/troubleshoot order I would start with the P0425 by inspecting the EVAP controller harness it might be broken from impact, inspect/fix the obviously pinched wiring while you're there and verify there isn't any OTHER damage to it. Next tackle the accelerator pedal, it's easy to unbolt and unplug the gas pedal, when you poke your head under the dash you'll see it comes off very easily. There is a wiring schematic in the FSM but basically it's two separate rheostat switches, you can rig up a test for it with the assembly removed and use a 3x AA battery holder to supply the roughly 5vdc to the lead side of the switch and use a digital multimeter to verify the voltage smoothly scales from 0.3 - 4.7 volts on the output side from no throttle to wide open throttle, the exact voltagesare in the FSM and are designed to be read with Consult - II but the battery trick works good, just make sure to test BOTH switches. If the switch is bad it can be individually replaced for about $35, don't need to buy the entire APP assembly for $150, use google and you'll find it. Fuel pressure is a pita because there isn't a factory test port, fortunately the folks at Z1 made a sandwich adaptor that goes between the fuel pressure damper on the passenger side and you can either permanently install a gauge (my recommendation) or install a test port. Be aware you need to purchase your own fuel gauge, if you want a recommendation just call Z1 and order over the phone, you usually get a better discount if you actually talk to them but you didn't hear that from me... >.> https://www.z1motorsports.com/z1-pro...rt-p-9160.html |
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