Artemis Posted April 5, 2009 Report Share Posted April 5, 2009 Not my car, but my friend Mickey's 95 GTP. Car was running fine yesterday.... well, we had it running until it shut off by itself. Its getting spark, the engine is turning over, and its getting fuel (checked fuel rail for pressure). So we figured the only thing left would be that the injectors aren't firing. Checked all the fuses in the two front fuse panels under the hood, everything seems fine! We took them all out and checked them, even cleaned them. Any thoughts as to why the injectors wouldn't be firing? Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted April 5, 2009 Report Share Posted April 5, 2009 Have you pulled the rail and injectors out of the LIM(leaving the wiring and fuel lines attached), and tried turning over the car to visually see that the injectors in fact are or aren't firing? Quote Link to comment Share on other sites More sharing options...
Artemis Posted April 5, 2009 Author Report Share Posted April 5, 2009 Have you pulled the rail and injectors out of the LIM(leaving the wiring and fuel lines attached), and tried turning over the car to visually see that the injectors in fact are or aren't firing? nope, but if they were firing..... and its getting spark, wouldn't something happen? Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted April 5, 2009 Report Share Posted April 5, 2009 How did you confirm its getting spark? Quote Link to comment Share on other sites More sharing options...
Timm Posted April 5, 2009 Report Share Posted April 5, 2009 How did you confirm its getting spark? Lol, but yea, filling all the cylinders with gas wont do much good without spark. They don't call it a 4-cycle engine for nothin! Quote Link to comment Share on other sites More sharing options...
Artemis Posted April 6, 2009 Author Report Share Posted April 6, 2009 How did you confirm its getting spark? took the plug wires out, used a screw driver between the wire and metal and started turning the engine over. The plugs and wires have literally 3-5kms on them. Spark is there. Quote Link to comment Share on other sites More sharing options...
92supreme Posted April 6, 2009 Report Share Posted April 6, 2009 Correct if you wanted to check for fuel one of the easy ways is after comfirming fuel press use a noid light. if not noid light not available. check for power 12v to each injector and then connect test ligh to the positve side of the battery and hold it on the negitive wire on the injector connector (with injector disconnected) and have somebody crank it over for you. see if you have the test light flickering if so your injectors have pulse. Quote Link to comment Share on other sites More sharing options...
jtwmechanic Posted April 6, 2009 Report Share Posted April 6, 2009 spray a little starting fluid in throttle body see if it starts. Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted April 6, 2009 Report Share Posted April 6, 2009 You may be getting spark, but is it at the correct time? A bad Crankshaft Position Sensor may give you spark still, but not at the correct timing, making it not run. Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted April 6, 2009 Report Share Posted April 6, 2009 I thought a bad CPS would be no spark at all. Quote Link to comment Share on other sites More sharing options...
jtwmechanic Posted April 6, 2009 Report Share Posted April 6, 2009 just try squirting a little srarting fluid in the throttle body, see if it will start. if it does then you know you have fuel issues and not spark issues. noid lights will tell you if the injectors are getting a pulse,they can be bought at most autoparts stores. process of elimination, start with the basics. afuel pressure guage will help you also. just because you have fuel at the rail doesn't mean there is enough pressure! Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted April 6, 2009 Report Share Posted April 6, 2009 I thought a bad CPS would be no spark at all. When Kyle's (Krenzy) TGP died at my house, it had spark and the injectors were firing, but it wasn't at the correct time. The CKP sensor had died. We replaced it with a new one and the car ran perfectly. Quote Link to comment Share on other sites More sharing options...
MickeyV Posted April 10, 2009 Report Share Posted April 10, 2009 Where is the best place to access the Crankshaft Position Sensor from? I took a quick look from underneath and from on top and I couldn't seem to find it. As I understand it the sensor is bolted into the block near the exhaust manifold and the firewall, is this correct? Any insight as to how to replace this sensor would be greatly appreciated. Thanks -Mickey Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted April 10, 2009 Report Share Posted April 10, 2009 What engine do you have? Quote Link to comment Share on other sites More sharing options...
89GP_SE Posted April 10, 2009 Report Share Posted April 10, 2009 your crank sensor or cam sensor may be out Quote Link to comment Share on other sites More sharing options...
jtwmechanic Posted April 10, 2009 Report Share Posted April 10, 2009 using a timing light on #1 cyl to watch the timing mark on the balancer and a noid light on #1 fuel injector, are they pulsing at the same time? little trick i use instead of swapping parts or guessing. did you squirt some starting fluid in tb to see if it will start on it. Quote Link to comment Share on other sites More sharing options...
Crazy K Posted April 10, 2009 Report Share Posted April 10, 2009 using a timing light on #1 cyl to watch the timing mark on the balancer and a noid light on #1 fuel injector, are they pulsing at the same time? little trick i use instead of swapping parts or guessing. did you squirt some starting fluid in tb to see if it will start on it. uh.... on a 3.1 MPFI they might NOT pulse at the same time since they are batch fired... do they even pulse at the same time on SFI car????? try some starting fluid if you have have spark... Quote Link to comment Share on other sites More sharing options...
jtwmechanic Posted April 10, 2009 Report Share Posted April 10, 2009 actually this is something i used on 3.8 4.2 4.6 ect. ford motors to get the cam sensor timed with the crank trigger. ford says you need a "special tool",instead of redesigning a engine they just adapted the distributor orfice to use a cam sensor set up, you can adjust the cam sensor manually on these(kinda like advancing or retarding a distributor). not that 60*v6's are anything like fords, but i figure the pulses should be close. my methods, my madness, my not work for you Quote Link to comment Share on other sites More sharing options...
Artemis Posted April 10, 2009 Author Report Share Posted April 10, 2009 Its an LQ1 he has. Im guessing he didn't get around to trying anything. But this weekend the weather will be decent, so if we have time when we're not taking apart my 3rd gen f-body.... Quote Link to comment Share on other sites More sharing options...
MickeyV Posted April 12, 2009 Report Share Posted April 12, 2009 As far as removing that sensor, any tips you guys might have? Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted April 12, 2009 Report Share Posted April 12, 2009 Be careful! You don't want that sensor snapping off in the block, so you will want to spray some PB (or lube of your choice) on it beforehand and then pull it out evenly. Some come out easily, and some can be a PITA. The original in my TGP took a good half hour of working it before it came out. Quote Link to comment Share on other sites More sharing options...
Artemis Posted April 25, 2009 Author Report Share Posted April 25, 2009 So Mickey and I replaced the Crank Position Sensor today. Same thing, injectors are getting 6-7volts when we crank them over... or so says the multimeter. Any reason why it wouldn't get the 12volts its supposed to? We really think its gotta be something simple like a fuse, but we can't figure it out. Any thoughts? Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted April 26, 2009 Report Share Posted April 26, 2009 Are both of your injector fuses good? Quote Link to comment Share on other sites More sharing options...
Crazy K Posted April 26, 2009 Report Share Posted April 26, 2009 So Mickey and I replaced the Crank Position Sensor today. Same thing, injectors are getting 6-7volts when we crank them over... or so says the multimeter. Any reason why it wouldn't get the 12volts its supposed to? We really think its gotta be something simple like a fuse, but we can't figure it out. Any thoughts? grab a small bulb, like the one used to light the glovebox or ashtray ( a bulb with a blade base about 1/2 inch wide) and bend out the wires and stick em into the injector harness. it should flash when cranked. a multimeter would interpret the on/off/on/off to an average value, instead of the max value seen. Have you checked for fuel? have you tried starting fluid? Quote Link to comment Share on other sites More sharing options...
Artemis Posted April 26, 2009 Author Report Share Posted April 26, 2009 Are both of your injector fuses good? If you mean the small 15-20amp fuses, then yes, we've checked and replaced them. Unless there's 2 other fuses that are larger we dont know about..... So Mickey and I replaced the Crank Position Sensor today. Same thing, injectors are getting 6-7volts when we crank them over... or so says the multimeter. Any reason why it wouldn't get the 12volts its supposed to? We really think its gotta be something simple like a fuse, but we can't figure it out. Any thoughts? grab a small bulb, like the one used to light the glovebox or ashtray ( a bulb with a blade base about 1/2 inch wide) and bend out the wires and stick em into the injector harness. it should flash when cranked. a multimeter would interpret the on/off/on/off to an average value, instead of the max value seen. Have you checked for fuel? have you tried starting fluid? I've checked the fuel line for fuel, its there, sprays out furiously if you press in the testing nozzle. We haven't tried starting fluid yet... I guess we should've picked some up at Canadian Tire when we were there yesterday. Quote Link to comment Share on other sites More sharing options...
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