Crank Position Relearn Procedure [Archive] - GrandAmGT.com Forum

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GrandAmGTTT
08-09-2009, 07:52 PM
I need to perform the crank position relearn procedure...can someone please tell me what that procedure is...?

Mike Jung
08-09-2009, 08:04 PM
You need (IIRC) someone with a Tech II tool or HP Tuner, etc... to do it.

GrandAmGTTT
08-09-2009, 08:05 PM
i have DHP tuner

AaronGTR
08-10-2009, 12:14 AM
In that case, open up your scanner. Go to the top of the window and click where it says "real time controls". There is an option for CASE learn. Click it and it will give you all the directions automatically and tell you when you've successfully completed it. Make sure the car is fully warmed up before you do it.

curtpank
08-10-2009, 12:17 AM
i have DHP tuner

if you mean DHP Powertuner, then you can do it yourself. It's called a CASE Learn variation test.

connect the DHP scanner to the car while it's running. Do this exactly as if you are going to log data. Then, in the scanner window toolbar click on "real time controls". Then choose Crank case position or whatever it's called - I don't have my scanner in front of me right now.

then just follow the step-by-step instructions. It takes about 15 seconds. Most mechanics around here will charge over $80 to do it!

curtpank
08-10-2009, 12:18 AM
lol! Aaron - you and I replied at the exact same moment with the exact same info! It's true what they say about great minds...

aiixon
10-12-2009, 04:01 PM
how can this be done without tuning software

AaronGTR
10-12-2009, 04:47 PM
how can this be done without tuning software

It can't. You need some type of hardware and software... either a laptop and DHP or HP tuner, or an automotive diagnostic and scan tool with that option... that can interact with the cars computer and activate the protocol for the crank position learn. There is no other way to do it.

aiixon
10-12-2009, 07:41 PM
i have access to an OBDII scan tool tonight, ill see if it has that option. Im thinking that's what I need to do to correct the timing after doing the head gasket swap, its running really rough and has huge misfires with higher RPM's that sound like metal on metal. I'm really hoping the valves aren't smacking the pistons or my life is over...

350rs
10-12-2009, 10:53 PM
OBD scanners that you get from your local parts store wont do it.

aiixon
10-13-2009, 12:05 AM
k my friends dad neighbor has a snap on scanner tool that can do all this crap but it only goes up to 1999. we tried it and it doesnt work on my 2000. so ill ask my shop teacher if he has one that i could either borrow or tow my car in to use

AaronGTR
10-13-2009, 12:16 PM
i have access to an OBDII scan tool tonight, ill see if it has that option. Im thinking that's what I need to do to correct the timing after doing the head gasket swap, its running really rough and has huge misfires with higher RPM's that sound like metal on metal. I'm really hoping the valves aren't smacking the pistons or my life is over...


Head gasket change would have nothing to do with this at all. The only time you need to do a CASE learn is if you change the pcm, the crank sensor, the crank pulley, or replace the entire crank shaft or engine. You shouldn't need to do a case learn from doing top end work.


When you changed the head gaskets and put everything back together did you make sure to put all the push rods back in the right order?

Malaclypse
10-13-2009, 04:53 PM
When you changed the head gaskets and put everything back together did you make sure to put all the push rods back in the right order?

First thing that came to mind. Or leave any of the rocker arms loose?

aiixon
10-13-2009, 09:27 PM
everything is done right trust me. somehow my timing is off by 30 degrees.

aiixon
10-13-2009, 09:46 PM
I think my engine was running SOOO poorly before that it timed itself to run really bad and it should run so much better now that it is too far of an adjustment. As far as I know relearning things on the computer is the only way to mess with timing on this car. Well besides down at the camshaft or crank but I didn't get that far.

AaronGTR
10-13-2009, 11:56 PM
I think my engine was running SOOO poorly before that it timed itself to run really bad and it should run so much better now that it is too far of an adjustment. As far as I know relearning things on the computer is the only way to mess with timing on this car. Well besides down at the camshaft or crank but I didn't get that far.


Nope, the engine can't "time itself to run bad". I can't relearn anything to do with timing either. It doesn't "learn" anything. It does average some numbers and make adjustments to fuel trims and to shift pressures based on driving habits vs time for wear and tear. That's about the limit of it.

Your timing is what it is. There is no learning or adjustment to make outside of what is programmed in the pcm and what the pcm sees from certain sensors. Your timing can't be off by 30 degrees.

Malaclypse
10-14-2009, 07:03 PM
I think my engine was running SOOO poorly before that it timed itself to run really bad and it should run so much better now that it is too far of an adjustment. As far as I know relearning things on the computer is the only way to mess with timing on this car. Well besides down at the camshaft or crank but I didn't get that far.

Sounds like you were looking at the Spark advance parameter in the ECM. 30 degrees of spark advance is pretty normal.

As Aaron says, there's no way to adjust spark timing on this engine. You've got a mechanical issue somewhere if you're hearing metal on metal noises.

Also, I don't mean any offense, but just because you tell us the job was done properly doesn't make it so.

aiixon
10-14-2009, 08:38 PM
Alright well when I was using a diagnostic scanner it said my timing was 30 degrees advanced.

I took it all apart, checked everything before I put it back together and all the parts were fine, juts normal wear. I took the heads to a machine shop and they were severely warped, but were salvaged and they were taken down to only 2 or 3 thousandths. When I put the engine back together I put all the gaskets on correctly and used RTV in the places it was needed. I used new head bolts. Everything was torqued to spec, and the push rods were in the right places. I put all the longer ones matched up with the exhaust valves and the shorter ones with the intakes. All hoses and connections, etc. were properly put back together. All wires and connections were connected.
The spark plug wires are in the right places, I checked 5 times. I didn't touch anything on the block.

What could be throwing the timing off?

2000 GT Coupe
10-14-2009, 10:51 PM
Alright well when I was using a diagnostic scanner it said my timing was 30 degrees advanced.

I took it all apart, checked everything before I put it back together and all the parts were fine, juts normal wear. I took the heads to a machine shop and they were severely warped, but were salvaged and they were taken down to only 2 or 3 thousandths. When I put the engine back together I put all the gaskets on correctly and used RTV in the places it was needed. I used new head bolts. Everything was torqued to spec, and the push rods were in the right places. I put all the longer ones matched up with the exhaust valves and the shorter ones with the intakes. All hoses and connections, etc. were properly put back together. All wires and connections were connected.
The spark plug wires are in the right places, I checked 5 times. I didn't touch anything on the block.

What could be throwing the timing off?
I am not sure it is as critical on this engine, though I would think so, each push rod needs to go back to the same valve as before, just having all exhaust ones going to exhaust and so on is not the same.

Malaclypse
10-14-2009, 11:26 PM
Alright well when I was using a diagnostic scanner it said my timing was 30 degrees advanced.

...

What could be throwing the timing off?

Missing the point. That's normal operation. You're supposed to have advanced timing when the engine is running. I've seen up to 40 degrees of ignition advance before under the right conditions.

Think of it this way. A distributor can have either a vacuum or mechanical timing advance which is dependant on engine speed and load. Eliminate the distributor and the ECM has to take over these functions.

So there's base timing for cranking and just after starting. Then there's ignition advance which is PCM controlled during all other conditions. This operates the same way as a distributor without all the mess. So base timing cannot be changed unless you start moving the reluctor wheel on the crankshaft or reprogram the computer.

The Spark advance parameter in a scan tool is just spark timing before TDC. It does not need to be 0 in an engine without a distributor.

Edit: OP's age is 14?! That explains alot....

aiixon
10-15-2009, 12:51 AM
I'm not 14 why do I always have to say that... But anyways about the pushrods, that's incorrect. It doesn't matter if they go back in the same order at all. They just need to be matched up correctly.

Okay so then why is my engine running so rough? I guess everything I figured out was wrong so I'm starting over from scratch.

aiixon
10-15-2009, 12:53 AM
post in other thread.

2000 GT Coupe
10-15-2009, 12:55 AM
I'm not 14 why do I always have to say that... But anyways about the pushrods, that's incorrect. It doesn't matter if they go back in the same order at all. They just need to be matched up correctly.

Okay so then why is my engine running so rough? I guess everything I figured out was wrong so I'm starting over from scratch.

Because that is what your age stats say. If it is incorrect you need to edit your personal info.

AaronGTR
10-15-2009, 09:46 AM
I am not sure it is as critical on this engine, though I would think so, each push rod needs to go back to the same valve as before, just having all exhaust ones going to exhaust and so on is not the same.


That is not correct. They need to go back to either intake or exhaust valve depending on their length, but they do NOT have to go back to the exact same valve they came off of. We use hydraulic lifters with pre-load predetermined by the rocker pedestal and the pushrods should all be the same length (or close enough within tolerances) for either intake or exhaust, so it does not matter.



As Malaclypse said 30 degrees of advance is common at certain times when the engine is running, so I don't think there's anything wrong with your timing either. The problem is somewhere else.


edit: and yeah, why don't you go in the user CP and edit your personal details already so it shows your correct age?

HighlyBoosted66
01-20-2010, 03:46 PM
so i changed my crank pulley and crank sensor(21x) that means i need a CASE relearn? the car runs fine until it gets fully warmed up and i let it sit for 10 mins at idle. thats what i dont get.

AaronGTR
01-20-2010, 09:43 PM
it's a 24x sensor, and yes you should get the case learn done. There is a very small chance that it won't need it, but 95% of the time if you change the crank pulley with the sensor ring in it, or change the pcm, it needs to be done. The engine will run without doing it yes... but it will run better after. Without the learn it defaults to base ignition timing. After the learn you should get a better idle and more low end engine response because it will be able to accurately read the crank position and adjust ignition timing for it under 3000rpm.

realestdriver
07-15-2010, 10:27 PM
didn't want to start a new thread, but I wanted to ask if 23-25* of spark advance at idle(warmed up) is normal? My 04' gagt only has about 16* but these two have become very different machines. I went to get a crank relearn today, but the snap on tool needed to be updated or something else. Tried to purchase a dhp tuner but guy never emailed me back, so I'm still looking for a place that can do it