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Sleepwalkr
03-16-2011, 09:53 PM
Does anyone have a diagram/drawing/pic of where might I find the Oil Pressure Sensor....... and same thing for the Cam Sensor.

Thank you

AaronGTR
03-17-2011, 03:45 PM
Oil pressure sensor does not exist. These cars do not have an actual pressure sensor for the oil. Just a pressure switch to activate the dummy light when the pressure gets dangerously low. That switch is screwed into the block right above the starter motor.

The cam position sensor is in the top of the block on the passenger side. It's kind of hidden behind the PS pump and the LIM, and is difficult to reach.

Sleepwalkr
03-17-2011, 08:10 PM
Cool. Thanks man.

BTW, do you think its possible that a bad pressure switch could be the reason that I'm not getting any spark and my car won't start? The computer my friend has narrowed it down to the oil pressure switch and a cam sensor....unless he's reading it wrong. I guess I'm just hoping I'm not gonna need new coils or a fuel pump. However, I can hear the fuel pump when I turn the key to "on".

bricooper78
03-17-2011, 08:22 PM
a quick and free test--pull the ignition module off, run into o'reilly auto parts and they have a tester for it. mine died out of the blue one day, never had any issues, it simply stopped. it was under a hundred for the new one, i'm thinking it was around 70 bucks, real easy switchout too.

AaronGTR
03-18-2011, 08:44 AM
Cool. Thanks man.

BTW, do you think its possible that a bad pressure switch could be the reason that I'm not getting any spark and my car won't start? The computer my friend has narrowed it down to the oil pressure switch and a cam sensor....unless he's reading it wrong. I guess I'm just hoping I'm not gonna need new coils or a fuel pump. However, I can hear the fuel pump when I turn the key to "on".


Nope. The switch has no function except to turn on the light. It has nothing to do with how the engine runs. Also the cam sensor won't stop it from getting spark. The PCM uses the cam signal to determine the position of the piston in cylinder #1 to initiate sequential fuel injection. It uses the 3x reference pulse from the ignition module to initiate injector pulses and control spark timing.

There is the 24x crank sensor, the 7x crank sensor, and the cam position sensor. All of those signals go through the ignition control module, and are used to control fuel injection and spark control. If any one of those signals is missing, it will use the other two as back ups. It may not run optimally since it will revert to a default timing map, and it may have trouble starting if the injector timing is off, but it should start eventually. Normally if the cam sensor isn't present, the PCM will run off the last known injector timing, with a 1 in 6 chance that it is correct.

The thing is, if any of those signals is missing, it will immediately set a DTC code and check engine light. Did you get either of those? And if two of those were missing or the ICM itself was bad, then the car wouldn't start because it wouldn't be getting any spark OR fuel. Again, that should set a DTC though.

Sleepwalkr
03-18-2011, 10:33 PM
Thanks again for the response.

Yes, I have gotten a check engine light kinda off and on for the last 6 months or so. It would come on for about a day and a half, then not come on again for 2 weeks, or even up to a month...then again come on for a day or two. I took it to Autozone after the second time the light came on, and their code said something about a small part in the engine, but it was for somehow "recycling the exaust"? I can't remember exactly. Unfortunately, I'm not very technically saavy when it come to motors and what parts are called. That particular part was like $75 and I should've just done it. However, would something like that cause the car not to start...or no spark?

This is not my car, but encircled in the part the guy at Autozone said was going bad.

AaronGTR
03-19-2011, 07:40 AM
Thanks again for the response.

Yes, I have gotten a check engine light kinda off and on for the last 6 months or so. It would come on for about a day and a half, then not come on again for 2 weeks, or even up to a month...then again come on for a day or two. I took it to Autozone after the second time the light came on, and their code said something about a small part in the engine, but it was for somehow "recycling the exaust"? I can't remember exactly. Unfortunately, I'm not very technically saavy when it come to motors and what parts are called. That particular part was like $75 and I should've just done it. However, would something like that cause the car not to start...or no spark?

This is not my car, but encircled in the part the guy at Autozone said was going bad.

Yeah, that's the EGR valve (exhaust gas recirculation). It has nothing to do at all with the car starting. It's mainly an emissions device. It allows a small amount of exhaust gas to enter the intake manifold under certain conditions to dilute the intake charge. Less oxygen to burn = less fuel required, plus it also helps control combustion temps, and reduces emissions by both methods.

It's not super critical, but you should fix it if you have the chance. If it's intermittent it could just need to be cleaned, but the valve itself could just be going bad too. You could try taking off the valve and the tube and spraying some carb cleaner through them to clean out the carbon deposits and see if that works. If not, replace it.

Sleepwalkr
03-19-2011, 02:11 PM
.

Sleepwalkr
03-19-2011, 02:11 PM
a quick and free test--pull the ignition module off, run into o'reilly auto parts and they have a tester for it. mine died out of the blue one day, never had any issues, it simply stopped. it was under a hundred for the new one, i'm thinking it was around 70 bucks, real easy switchout too.

I heard it was located under the coil packs. Is this true, and what kind of tools do I need to get it out of there?

AaronGTR
03-19-2011, 06:31 PM
Yes, it the thin black plastic thing that the coils sit on top of. It's got two plugs on the right and one on the left. Basically you just unplug everything, unbolt the coils and remove them, and it will pull right off.

Sleepwalkr
03-20-2011, 09:32 AM
Alright cool. Thanks again. Ok, I pulled off the coils, then the ignition module. Only took like 10 minutes. So I took it down to Autozone and they tested it. It came up as being ok. I was actually bummed, hoping it came up bad so I could just buy another one and spend 10 minutes putting it in and voila, car fixed.

So I talked to the guy there and he said pretty much the same thing you did about removing the Cam position sensor & the crankshaft position sensor. So, thats my chore for the day. I'm looking all over the internet for a nice drawing/diagram/pic of these 2 things. I think I'm gonna remove the front passenger side wheel and splash guard and try to get to them that way. Hopefully I can do it and fix the issue. These, I thin are my last 2 options before it starts to get kind of expensive.

Sleepwalkr
03-23-2011, 09:48 PM
Ok, so I have a mechanic buddy of mine who's been over twice this week with his scope and even he can't quite figure it out. We replaced the crankshaft position sensor; nothing. I had my ignition module tested; its fine. The cars' computer is fine. We're still not sure. but he's bound & determined to figure out my car for me. Any other suggestions?

bricooper78
03-24-2011, 08:52 AM
are you sure you have no spark?

have you put a gauge on the fuel rail to see if you have enough fuel pressure?

A weak pump will still make noise, but won't supply enough power to let the thing run.

IIRC you want around 55lbs of pressure, I know that 50 or lower was bad, but I can't remember the actual number.....Aaron??

AaronGTR
03-24-2011, 10:24 PM
55psi at WOT, or with the ignition on, engine off, and vacuum tube off the regulator (basically a no vacuum state, same as WOT). This should equate to around 48psi at idle on most cars, dependent on how much vacuum you are pulling. Higher vacuum=lower pressure.

Sleepwalkr
03-25-2011, 08:41 PM
are you sure you have no spark?

have you put a gauge on the fuel rail to see if you have enough fuel pressure?

A weak pump will still make noise, but won't supply enough power to let the thing run.

IIRC you want around 55lbs of pressure, I know that 50 or lower was bad, but I can't remember the actual number.....Aaron??

We pulled the caps off of the coils and held them down to the rods coming off the coils and there was nothing. According to my mechanic buddy, the fuel pump has "plenty of power". I wasn't there when he did it, but he told me that he took off a hose or something and the fuel shot out pretty strong.

Anyways, we're taking my car down to another shop owned by a good friend of my father-in-law tomorrow morning, and he's gonna hook it up to a machine that I guess costs $15k and will "diagnose" the problem. Heres to hoping huh?

bricooper78
03-26-2011, 06:44 PM
yea man, keep us updated. it could just be some little dumb gremlin, or i'll hope for ya it is at least

Sleepwalkr
03-31-2011, 07:06 PM
UPDATE;

Ok, so the mechanic friend of my father-in-law fixed my car. Guess what it was?....... the damn ignition module. Yes, the same one that I pulled out and had tested at Autozone and they said was just fine. So question; What good is having something tested at Autozone if it doesn't come up bad...when it IS bad? Anyways, now I owe the guy $200 when I could've gotten away with spending $90 on the part and doing it myself in like 20 minutes. Oh well, at least its running again. I'm gonna go pick it up Saturday morning.

So now, at some point, apparently I need a new water pump as well. Its leaking coolant...not bad, but leaking. I can keep coolant in it for a while, but as soon as I have the money, I'm gonna need to replace it. I already know thats gonna be even more fun.

Anyway, thanks guys for the info and your time.

Sleepwalkr
10-16-2011, 09:23 PM
I hate to bring up this thread again.....

My car won't start again. Its doing the exact same thing where it cranks and cranks, but won't start up. I bought a new Ignition Control Module; that didn't work. I replaced one of the coil packs that one of the prongs sticking up looked bad; that didn't work. I replaced the 3 front spark plug wires (2,4,6); that didn't work. I checked all IGN fuses; they're fine. My fuel pump is working fine and I replaced the fuel filter less than a year ago. Car just won't start and it bummed me out big time today. Even my daughter came up and gave me a hug. hehe. Car ran perfectly fine until the other morning when it wouldn't start... so if I can get it started, it runs ok.

Any more ideas why she won't start this time guys?

Thanks.

icecats87
10-16-2011, 09:37 PM
I hate to bring up this thread again.....

My car won't start again. Its doing the exact same thing where it cranks and cranks, but won't start up. I bought a new Ignition Control Module; that didn't work. I replaced one of the coil packs that one of the prongs sticking up looked bad; that didn't work. I replaced the 3 front spark plug wires (2,4,6); that didn't work. I checked all IGN fuses; they're fine. My fuel pump is working fine and I replaced the fuel filter less than a year ago. Car just won't start and it bummed me out big time today. Even my daughter came up and gave me a hug. hehe. Car ran perfectly fine until the other morning when it wouldn't start... so if I can get it started, it runs ok.

Any more ideas why she won't start this time guys?

Thanks.

Is the security light flashing? Does it just crank and crank and crank just not turn over? And how olds the battery?

If security light is flashing it needs to do a re learn for the pass-lock. Make sure the battery is fully charged. Try to crank the car it wont start leave it in the "on" position for about 10 min or so, it might take longer or shorter but the security light will go out or stay solid. Once it does turn the key off for 10 seconds and then it should start.

My car did this a few weeks ago, was working fine then out of no where it would crank and crank and crank, battery was dead and the security light was blinking so i did this, and no problems since.

[ChaosweaveR]
10-16-2011, 09:57 PM
I'd go after the fuel pressure. Possible bad pump by the sound of it.

And come on, dude...only changing three plugs? Running on mismatched/old/new plugs certainly isn't going to help your issue. I'd replace the wires, too.

Sleepwalkr
10-17-2011, 07:42 PM
Is the security light flashing? Does it just crank and crank and crank just not turn over? And how olds the battery?

If security light is flashing it needs to do a re learn for the pass-lock. Make sure the battery is fully charged. Try to crank the car it wont start leave it in the "on" position for about 10 min or so, it might take longer or shorter but the security light will go out or stay solid. Once it does turn the key off for 10 seconds and then it should start.

My car did this a few weeks ago, was working fine then out of no where it would crank and crank and crank, battery was dead and the security light was blinking so i did this, and no problems since.

I'm pretty sure its not the Security issue. I had that happen to me a couple times, a year or so ago and I knew what to do then...but its not the same this time. Plus, no, the Security light is not flashing. Thanks though.

Plus, about 3 weeks ago, my security light came on while I was driving. I looked it up in the manual, and it stated that the PassLock was not functioning properly. My car has started fine and run fine since then, with no security light. Besides, wouldn't all that mean is that it wouldn't do the 10 minute re-learn things anyways?

Sleepwalkr
10-17-2011, 08:08 PM
;1165559']I'd go after the fuel pressure. Possible bad pump by the sound of it.

And come on, dude...only changing three plugs? Running on mismatched/old/new plugs certainly isn't going to help your issue. I'd replace the wires, too.

Yes, I know I need to replace the back 3 plugs and wires as well, but I was trying some stuff while I had time over the weekend. I think my fuel pressure is fine... though I'm not 100% convinced of it. I guess I'll probably end up looking in that direction eventually. Unfortunately, I'm running out of the "cheaper" idea's.