15psi

The chain tensioners have to be loosened, to take some pressure off the chain and the bearing. If you don't loosen them, the bearing will move as seen in the picture as the cover is removed. Also much easier removing the cover with the tensioners loosened.

mmasse

I just finished the clutch/RMS/IMS job and when I turned the engine on the Check Engine Light went on. I checked the code and I get: code P0348 Camshaft Position Sensor "A" Circuit High.

I had checked the position of the cam after installing the new IMS cover (following the instructions above) and the position looked correct.

What could be the reason for the code? is the cam timing screwed?

Thanks in advance for your help
Thanks

Jake Raby

Yes, the tensioners MUST be removed before ANY IMS procedures can be accomplished without complication. You must also rotate the engine to TDC #1 and lock the crank to ensure the crank doesn't rotate during the procedures, thus altering the cam timing.

The reason why the IMS bearing becomes off center when the flange is removed is due to the forces being applied to it by the chain tensioners.

Now that the engine in question has had the IMS bearing flange pulled while the tensioners were in place I would verify the cam timing. I have done this in the past and experienced a 4 degree cam timing alteration on the 1-3 bank of cylinders. Never assume. Always verify. These engines have very tight piston/valve clearances and you don't want to experience what happens when things collide.

mmasse

Jake,
I understand I screw up. Now, I want to understand how much!!

For me it is clear that the timing has been affected, because I am getting the CEL and the mentioned code.

Now, I am stuck on how to proceed, or what the implications are. The engine starts and there seems not to be any noise. I drove the car around the block to test it for the clutch and there were no signals on anything wrong. So, I guess that the timing could have been affected by a small amount, because if not I should have destroyed the engine, right?

Is there any other way to check the timing other than to take it to a dealer?

Thanks again

Eharrison

I hope this turns out for the better buddy! That's got to be a sinking feeling.

mmasse

Well, it is clearly not nice, but there is some cost associated with learning...I am just happy it was not the full engine!!

Maybe I can now learn how to adjust the cam timing :-)

Jake Raby

I could rent you my cam timing tool and walk you through the procedures.
The dealer probably doesn't know how to do it. (seriously)
They are experts at changing engines out!

Dharn55

If Jake will rent you his Cam Timing tools that would be very helpful. You can also buy a tools for this, the Porsche tool is the 9612. The first link below has the exact tool that Porsche uses (or an exact replica) and the second is a ebay source for a tool that does the same thing. I think the Baum tools one is over $400, the other $216.

http://www.baumtools.com/pdf/porsche_timing_tools.pdf

http://cgi.ebay.com/ebaymotors/Tool-...motiveQ5fTools

The way these tools work is to lock the exhaust cam in place while you set it to the crankshaft/IMS. To do this you have to remove the green caps, one on the intake cam on the driven end of the cams (front of the engine/car on 1-3, and rear of the engine/car on 4-6) and two on the opposite ends of the cams. For 1-3 you lock the crank at TDC, you don't have to buy the tool for this, I use a torqueX wrench that is the same diameter of the tool that fits into the pully on the end of the crank. (if you don't have service manuals you might want to get a set) You can tell that 1-3 is at TDC by the grove on the drive end of the intake cam, it should be pointing to the outside of the engine, if not you need to rotate the crank 360 degrees. Then you have to remove the scavenger oil pump to get at the sprocket that drives the exhasut cam off the IMS by chain. There are four bolts that hold the sprocket to the end of the cam. You have to loosen these. Porsche says to use special pretensioners, that replace the tensioners (3) on the cam to IMS chains and the IMS to crank chains. But the actual tensioners should be sufficient for this unless they are bad.

Now the 9612 tool bolts onto the head at the non-drive end where the two caps were removed. Part of the tools fits into the head opening on the intake cam where the green cap was removed to help hold the tool in place. The other end of the tool fits into the grooves on this end of the exhaust cam. The grooves are slightly offset, and the smaller side is towards the outside on the engine. The tool, which is very heavy duty, allows you to rotate the exhaust cam and locks the grooves straight up and down. Remember that the rotation has to be done after the bolts holding the sprocket in place are loosened. Now once the camshaft is held in the proper position, with the grooves straight up and down, narrow side out, and with the crank at TDC, you retighten the sprocket bolts, and the cam timeing is set.

I tried to make a tool from a socket to fit into the grooves to do this. The socket fit, but there was no way I could get enough pressure on the socket to hold the tool on the end of the cam, the valve springs put alot of pressure on the cam rotating it.

I do have a shade tree mechanic approach that accomplished the same thing without the tool. Not sure if Jake would approve, but here it is. After I reinstalled my head after having a crack fixed I also had a cam timing error. So I set 1-3 at TDC as described above and removed the green cap on the driven end of the intake cam to be able to see the groove on it, and only the green cap on the exhaust cam on the other end (remember that you will have to get new caps as they are hard to get out without damaging them, and they go for about $9.00@). The cam appeared to be 10-20 degrees off. So I loosened the bolts on the sprocket and then took out the pin on the crank pulley and used a socket to rotate the crank in the appropriate direction, you have to figure this out by which way the cam is off. Guesstimated how much to rotate the crank, retightned the bolts on the sprocket, returned the carnk to TDC and checked the end of the cam to see if the grooves wer straight up and down.

On the 1-3 side I got it about a perfect as possible on the first try. When I went to do the 4-6 side it took two or three tries to get it just right. Obviously the tool is simpler, but this worked and I did not have to buy the tool.

So if Jake will rent you the tool, and it is available when you need it that is the best bet. Or buy a tool. But you can get them set with my method.

By the way, the dealer near me had the tools, and said they had not used it in several years. A mechanic showed me the tool so I could see exactly how it worked. He said he would like to let me borrow it, but the dealer would fire him if they found out.

mmasse

Jake, Dharn55

THANKS A LOT for your inputs.

Jake, it would be great if you could rent me the tools. I could give you a deposit for the total value while I have them. I will send you a PM with my email and phone.


Dharn55, I do have the service manuals, but I have normally found that unless you have done the procedures at least ones, the manual is difficult to follow. So, once I have the tools, I will rely on you and Jake to do it.

Today I reset the code to see if it came back on, and indeed it did. I also got the following info from the scantool, but it only give me info on the cam on Cyl #1, which I guess is not very helpful.

But, I guess I will now learn how to set the timing

Dharn55

mmasse - What is the Scantool that you are showing? I have the Durametric, but yours seems to show alot more info than my Durametric.

porsche52

Now, now Jake... Not all the techs in the dealer network are retarded!!!! Some are, but not all. I get your point, but I also take offense, because I am at a dealer and know how to time all our engines.

Kudos to you guys and your IMS products. We have installed several, very nice product.

porsche52

Quick question. Is the cam position sensor plugged in. The fault description you wrote down is incomplete, Circuit High..... high what? resistance? "open circuit". "Above limit value" With your scan tool, can you look at camshaft deviation? If the cam timing is off, you will see it with this value. All the values in your screen shots are of no help. What year is this 996???

mmasse

I am using a a reader from ScanTool.net

What I posted is all the info i get. There are some other pages but the data would show as N/A

Porsche52, where are the sensors you refer to...anyway after my scrw up in taking out the IMS cover, it should be no surprise that the timing is of, I guess.

porsche52

This is the fault printout and diagnosis steps for fault code P0348. Special tool 9637 is a electrical pin-out box. Special tool at Dealer, maybe some indy's have one too. My guess is you have a faulty bank 2 cam sensor and or the signal wire from the sensor to the DME control is indeed shorted to B+. The camshaft position sensors are located next to the green cam plugs you removed to check camshaft timing. They are a two pin sensor, monitor intake camshaft position for each bank. Bank 2 sensor would be on the transmission side of the motor, next to green cam plugs.
P0348
Camshaft Position Sensor 2 – Above Limit
Diagnosis conditions
• Engine running
Possible fault cause
♦ Short circuit to B+
♦ If both CMP sensor signals are missing, the start will take at
least 10 seconds.
♦ For safety reasons, the ignition timing is retarded.
Affected terminals
Terminal III/18
Diagnosis/Troubleshooting
Note!
Work instruction Display OK If not OK
1 Check signal wire from
DME control module,
Pin III/18, to CMP sensor
for short to B+
♦ Connect special tool 9637 to
wiring harness (DME control
module plug).
♦ Remove connector of CMP sensor
2
♦ Switch on the ignition.
♦ Measure voltage between special
tool 9637 pin III/18 and
ground.
0 V Repair wiring harness
→ End. → End.

mmasse

Porsche52,

Why are you guessing the issue is on Bank 2 (passenger side, right?), is there anything on the default code that tells you that.

From your previous post I get that the fault description is incomplete, but unfortunately its all I get.

Btw, my car is a '02 C4S.

I wiil check the sensor just in case.

Best