are you sure that if the camshaft position sensor is bad the engine wont run. ... want to know
- posted
17 years ago
are you sure that if the camshaft position sensor is bad the engine wont run. ... want to know
99% of the time when the cam or crank sensor fails, the engine won't run. All those sensors do is tell the ECU when either the cam or the crank has rotated. It does that by sending a pulse (a zero or 1 if you will) at each rotation. They normally don't fail in a "sometimes it works, sometimes it doesn't" fashion. It either works or it doesn't. Without that signal, the engine shouldn't start.
Cheers,
thanks ritz one more quesstion hope you dont mind . are you a auto mechanic. IS EVERYONE HERE AUTO MECHANIC EXCEPT OF COURSE THE ONE THAT HAVE A PROBLEM:)
Yes, I am, though I don't do it for a living anymore. I'm certified by ASE (which is pretty Mickey Mouse), Audi, VW, and Porche. My knowledge of Fords comes from being a long-term Mustang enthusiast.
Cheers,
As mentioned before Saturn 1.9's dont have a cam sensor.
Actually most can run without the cam sensor but not without the crank sensor.
bla bla hi again i went today to saturn dealer and show them what i learn from you they dont want to listen they want me to spend money. you told me there is no camshaft position sensor on saturn SL1 1996 1.9 they said they have its 163.35 dollar . im tryin so hard to go easy way . i went to another shop they told me the same way they told me they well order it for me take 2 days i need to bring at least 300.00 for the part n labor. waht do i need to do only got 30 days
Huhhhhhhhh? I went to advanceautoparts.com and found NOTHING under cam sensors. I went to AutoZones website and a cam sensor actually did pop up in the search for about $13 bucks... What is it they have for 13 bucks??? What is it the dealership has for $163 bucks??? I haven't a clue because I found NO information on installing or testing a cam sensor in my "GM Service Information" program.
What I did find is the following if you want to print it out and slap it down on the counter for them to read. Far be it from me to tell a Saturn Dealership how to work on Saturns... So I'll let the GM Manual Making Gods do it.
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------------------ 1996-98 Saturn S-Series -----------------------------
------------------------------------------------------------------------ MIL Service Engine Soon Telltale On with DTCs P0340 and/or P0341, Cam Sensor Circuit Performance #98-T-49A - (01/06/2003) (MIL) SERVICE ENGINE SOON Telltale On with Diagnostic Trouble Codes (DTCs) P0340 and/or P0341, Cam Sensor Circuit Performance (Diagnose and Repair as Necessary using Updated Diagnostic Information Contained in this Bulletin) This bulletin has been revised to incorporate the ignition coil assembly (P/N 1616773) as a service part and supercedes bulletin 98-T-49, which should be discarded.
1996-1998 Saturn S-Series vehicles ConditionVehicle may experience the (MIL) SERVICE ENGINE SOON telltale On with DTCs P0340 and/or P0341. Cause
DTCs P0340 and P0341 may be caused by incorrect resistance in the secondary ignition system. This incorrect resistance can cause the EI Module to incorrectly signal the cam position to the PCM.
Correction
The diagnostic information for DTCs P0340 and P0341 has been updated to included inspection of various secondary ignition components.
Object Number: 886114 Size: MF Click here for detailed picture of above image. CMP SENSOR CIRCUIT PERFORMANCE (Chart 1 of 2)
For complete description of circuit operation, refer to Circuit Description on page 6 of this bulletin.
DIAGNOSTIC AIDS
Important
A cam pulse signal error may not effect engine operation.
Notes on Diagnostic Chart 1:
Important
After saltwater spray test is complete, engine compartment must be rinses thoroughly with clean water. 3. Use a 10 percent saltwater solution for best results. Start misting the EI module and spark plug terminals at the EI module first, then mist each spark plug wire from the EI module to the plug. flow chart missing
Object Number: 886114 Size: MF Click here for detailed picture of above image. CMP SENSOR CIRCUIT PERFORMANCE (Chart 2 of 2)
For complete description of circuit operation, refer to Circuit Description on page 6 of this bulletin.
DIAGNOSTIC AIDS
Important
A cam pulse signal error may not effect engine operation.
Notes on Diagnostic Chart 2:
Object Number: 886114 Size: MF Click here for detailed picture of above image.
The cam signal is a 5 volt signal (circuit 633) that is pulled to ground to inform the PCM that #4 cylinder has fired on compression. A much higher voltage is needed to fire a cylinder that is on the compression stroke. The EI module monitors this firing voltage on the #1--4 coil to determine if cylinder #1 or cylinder #4 is firing. This signal, along with the double pulse received from the CKP sensor, synchronizes fuel timing.
Under normal operation, the 7X (CMP RESYNC) COUNTER continuously counts the notches in the crankshaft as it rotates, and resets to zero each time the CMP sensor detects the #4 cylinder firing. Therefore, the 7X (CMP RESYNC) COUNTER should continuously count from 0 to 14 with each two crankshaft revolutions. If the cam signal is missing, the 7X COUNTER will count to 255 and stay fixed and P0340 will set. If the cam signal is present too often, the counter will not reach 14 and a P0341 will set.
If the ignition secondary (coil, pair of spark plugs wires) has incorrect resistance, open or corrosion in the circuit that influences firing voltage, the EI module can incorrectly interpret these voltages and cause codes P0340 and/or P0341 to set. Procedures
Parts Requirement
DOHC (LL0) Engines
21024465 Wire Asm - Splg (Cylinders 1 & 4)21024466 Wire Asm - Splg (Cylinder 2)
21024467 Wire Asm - Splg (Cylinder 3)SOHC (L24) Engines
21024472 Wire Asm - Splg (Cylinders 1 & 4)21024473 Wire Asm - Splg (Cylinder 2)
21024474 Wire Asm - Splg (Cylinder 3)All Engines
21024473 Module Asm - Elec Ign Cont16167763 Coil Asm - Ign
Important On 1996 vehicles, if spark plugs are replaced, and vehicle was equipped with 0.060 in gap plugs, all four spark plugs and "Vehicle Emissions Control Information Label" must be replaced. Refer to Technical Information Bulletin 96-T-25, "Engine Cranks but will not Start, or Engine Stalls Immediately After Start Followed by Extended Cranking, and/or Ignition Misfire Resulting in DTCs P0300, P0301, P0302, P0303, P0304." Claim Information
To receive credit for this repair during the warranty coverage period, submit a claim through the Saturn Dealer System for one of the following depending on repair performed:
Case Type Description Labor Operation Code Time VW Wires, Spark Plug - Replace one or two J4206
0.3 hrs Add: A. To replace all spark plug wires 0.1 hrs VW Module, Electronic Ignition (DIS) - Replace J4343 0.6 hrs Add: A. To replace all spark plug wires 0.1 hrs VW Coil, Electronic Ignition Module - Replace J4345-- Add: A. To replace each additional coil
0.2 hrs B. To replace all spark plug wires 0.1 hrs------------------------------------------------------------------------
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Here's one more thing you can print out for them.
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------------------------------------------------------------------------ COMPRESSION SENSE IGNITION
Both the SOHC and DOHC engines utilize Compression Sense Ignition, which eliminates the need for a camshaft position sensor. The EI module has sensing circuitry that detects when cylinder #4 has fired on its compression stroke and relays this information to the PCM. The PCM can then correctly synchronize the fuel injectors for sequential fuel injection.
The EI module uses capacitive pickup plates located under the 1/4 coil to determine when cylinder #4 has fired on compression. These plates are used to differentiate the polarity and voltage amplitude difference between the 1/4 secondary ignition circuits. Since each coil tower is of opposite polarity and the waste spark (2-4 kV) generally fires before the compression spark (10-25 kV), the module can determine cylinder #4 compression. When the EI module detects a positive to negative polarity sequence and a high negative voltage spike, it will pull the PCM 5-volt cam signal circuit to ground. The PCM knows that cylinder #4 had just fired on its compression stroke when this transition occurs.
The EI module, however, cannot always detect when cylinder #4 has fired on compression. These occurrences include the following:
Too few cam pulses (cam signal circuit not being pulled to ground) are a result of decreased cylinder #4 secondary resistance or increased cylinder #1 secondary resistance. Too many cam pulses, cam signal circuit being pulled to ground too often, are a result of decreased cylinder #1 secondary resistance or increased cylinder #4 secondary resistance.
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thanks bla ba im gonna try again:) its kind a hard to go back again to saturn dealership they wanna sell me a car:) can anybody do this job? i mean can i buy a spark plugs then buy wires? let auto zone check or advanced auto check the wires make sure its 15ohms or i need to go to dealership to get it tested
one more thing bla bla do you have by chance have a image of the saturn ingine were the coil are and what they look like. if not its ok you already help me me enough .. thanks to you
whats knock sensor
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