car wont start
Originally Posted by LS1-450
Got your PM. If the crank reluctor is from the same model year, it should be ok. Fuel, spark, crank, cam can be confirmed @ the PCM. Get a pin out sheet for your model year PCM & have a look. Can also check spark by pulling a plug wire & cranking (might crack a plug). I don't know what to say about having no MAF. Are you using an after market PCM?
If she cranks & won't start, there's most likely a spark or fuel issue. If the PCM is getting power (confirmed by that fact that you can connect to it through the OBDII port), then it's likely an external electrical issue. Check fuel pressure once fuel pump relay & fuse power have been confirmed. Quadrouple check your grounds or that no in-line fuses were added somewhere that could be adding to the problem.
I have also gone through this **** for four months & know how frustrating it can be. Mine turned out to be a wiring issue related to combining Mazda & GM wiring. Bottom line was no fuel or spark.
If she cranks & won't start, there's most likely a spark or fuel issue. If the PCM is getting power (confirmed by that fact that you can connect to it through the OBDII port), then it's likely an external electrical issue. Check fuel pressure once fuel pump relay & fuse power have been confirmed. Quadrouple check your grounds or that no in-line fuses were added somewhere that could be adding to the problem.
I have also gone through this **** for four months & know how frustrating it can be. Mine turned out to be a wiring issue related to combining Mazda & GM wiring. Bottom line was no fuel or spark.
already took out a plug and check if it spark and it did, friend said it was kinda week but it was because the ground sensors were connected together in the back of the head, well at least what i think..
no maf because i was running open loop tuning, then when the motor took a dump it was getting tuned for sd tuning which doesnt require maf either..
im going to check all grounds again and check m fuses one more time. but any other suggestions
Teching In
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I've run into this before... I worked at a GM dealership for a long time... anyway, this sounds like there is a theft system problem. That usually stops the fuel injector pulse. The esaiest way to seel if the PCM is comanding fuel inj pulse is with a "Noid Light". They are 5-10$. If you have a Harbor freight store arround it is 7$ for a whole kit of 6 of them. As far as checking spark, use a spare plug, and plud it into one of the wires to the coil, and hold the threaded body of the plug ot the motor, (heads or something to complete the ground or else you are going to get one hell of a shock... it hurts) and then have someone crank the motor. you should have spark, and the noid light should flash each time the PCM comands spark.
As far as the new crank sensor, you will need a relearn, I don't know if aftermarket scanners can do this, but we always did it with a tech2. The same thing goes for the cam position sensor.
Does your check engine light come on when you turn the key on, but not far enough to start it?
As far as the new crank sensor, you will need a relearn, I don't know if aftermarket scanners can do this, but we always did it with a tech2. The same thing goes for the cam position sensor.
Does your check engine light come on when you turn the key on, but not far enough to start it?
Originally Posted by allgood57
I've run into this before... I worked at a GM dealership for a long time... anyway, this sounds like there is a theft system problem. That usually stops the fuel injector pulse. The esaiest way to seel if the PCM is comanding fuel inj pulse is with a "Noid Light". They are 5-10$. If you have a Harbor freight store arround it is 7$ for a whole kit of 6 of them. As far as checking spark, use a spare plug, and plud it into one of the wires to the coil, and hold the threaded body of the plug ot the motor, (heads or something to complete the ground or else you are going to get one hell of a shock... it hurts) and then have someone crank the motor. you should have spark, and the noid light should flash each time the PCM comands spark.
As far as the new crank sensor, you will need a relearn, I don't know if aftermarket scanners can do this, but we always did it with a tech2. The same thing goes for the cam position sensor.
Does your check engine light come on when you turn the key on, but not far enough to start it?
As far as the new crank sensor, you will need a relearn, I don't know if aftermarket scanners can do this, but we always did it with a tech2. The same thing goes for the cam position sensor.
Does your check engine light come on when you turn the key on, but not far enough to start it?
i did check spark before and saw it..
the light does stay on but i checked it with a machine that my friend has handheld and it plugs into the computer plug in thing in the car and no codes show up when it scans??
Last edited by pewter 01 SS; Sep 13, 2006 at 02:03 PM.
Originally Posted by allgood57
I've run into this before... I worked at a GM dealership for a long time... anyway, this sounds like there is a theft system problem. That usually stops the fuel injector pulse. The esaiest way to seel if the PCM is comanding fuel inj pulse is with a "Noid Light". They are 5-10$. If you have a Harbor freight store arround it is 7$ for a whole kit of 6 of them. As far as checking spark, use a spare plug, and plud it into one of the wires to the coil, and hold the threaded body of the plug ot the motor, (heads or something to complete the ground or else you are going to get one hell of a shock... it hurts) and then have someone crank the motor. you should have spark, and the noid light should flash each time the PCM comands spark.
As far as the new crank sensor, you will need a relearn, I don't know if aftermarket scanners can do this, but we always did it with a tech2. The same thing goes for the cam position sensor.
Does your check engine light come on when you turn the key on, but not far enough to start it?
As far as the new crank sensor, you will need a relearn, I don't know if aftermarket scanners can do this, but we always did it with a tech2. The same thing goes for the cam position sensor.
Does your check engine light come on when you turn the key on, but not far enough to start it?
allgood57 makes a good point regarding VATS (vehicle anti theft system). I hadn't thought about VATS. Easiest thing for you to do is to ask your tuner if VATS is causing the problem. It can be disabled if you like or @ least verified as being the cause of the problem.
Originally Posted by LS1-450
allgood57 makes a good point regarding VATS (vehicle anti theft system). I hadn't thought about VATS. Easiest thing for you to do is to ask your tuner if VATS is causing the problem. It can be disabled if you like or @ least verified as being the cause of the problem.
thats exactly what imgoing to do..i rechecked everything and it was fine so since i bought a cam sensor and cant return it im going to install it and take it to the shop so he can see if VATS or injector pulse is causing the problem. i just hope it is something elec or wire prom that he can find and not the reluctor....
You can't relearn the crank or cam if the engine doesn't run. The crank relearn requires you to rev the motor to around 4000rpm. I'm battling a similar issue right now. Car is only running on 4 cylinders, won't rev above 1000rpm, DTC P0336(Crank position sensor range/performance). I've determined that the reluctor wheel was installed incorrectly by the professionals. I'm having them fix it on Monday and hopefully it will run.
Originally Posted by Ferocity02
You can't relearn the crank or cam if the engine doesn't run. The crank relearn requires you to rev the motor to around 4000rpm. I'm battling a similar issue right now. Car is only running on 4 cylinders, won't rev above 1000rpm, DTC P0336(Crank position sensor range/performance). I've determined that the reluctor wheel was installed incorrectly by the professionals. I'm having them fix it on Monday and hopefully it will run.
how did they determine that?? did they have to take out the motor to see that? to fix it the motor has to be pulled right??
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Verdad Gallardo I took pictures of the motor as I was building it. I then compared the pics of the reluctor wheel to the one on my stock crank and it wasn't even close. I've already dropped the motor and will have the crank out in a couple hours, then I'm going to take it to them tomarrow so they can fix it.
Originally Posted by pewter 01 SS
how did they determine that?? did they have to take out the motor to see that? to fix it the motor has to be pulled right??
Have you confirmed that VATS is not the problem?
Originally Posted by LS1-450
Have you confirmed that VATS is not the problem?
not yet the guy who im taking my car to was not available on friday so im taking it, hopefully tomorrow and leaving it there.. hes going to check VATS, pulse in the injectors and all the problems that you suggested.. thnx for the help guys, ill keep an update in the next few days.
Whats the lastest? I am having a similar problem. One thing I will add is that the car will run with a bad cam sensor. The crank sensor is the one that has to be right for the car to start. Post up.
no updates yet, i took it to a shop that was more knowledge and havent heard anything yet. i was told the reluctor wheel was checked and it is good so now im just waiting to see if its something else.
Originally Posted by 67SS&99Z28
When you go to crank your car, and you turn it on to let the fuel pump prime, does the security light go out? VATS is usually the issue when this light stays on.
the only light i remember staying on is the check engine but when i go and scan it nothing comes up. but on the other hand im using a scanner from auto zone, maybe its not good enough
Originally Posted by Lafngas98Z
Usually when the VATS is kicking in the car will start then die. This is what I have learned from my research.
interesting good find.. my car doesnt even start..
just got some news, talked to the shop that is working on my shop and they said they still cant find the problem, they checked, spark,fuel, compression test, re flased the computer and still doesnt want to start. he said that maybe was put in incorrectly but since the machine shop put it in i would of figure they put in correctly.. i remember piston 1 being all the way up and the dots allined..