grinder11

iTrader: (1)

There are truly some very, VERY smart people on this forum. Not to flatter anyone, just the truth. I consider myself in this group, as well as some of the "tuner" company people I have spoken with. These include, but are not limited to, Kurt Urban, Billy Briggs and company at Wheel to Wheel Powertrain, Tony Mamo@ AFR, Andy@ A&A Corvette, the guys at Cartek, Jason@ Katech, LG Motorsports, Steve@ Race Engine, I think you get my point. I hope and pray that someone out there can help my car. Tony Mamo@ AFR suggested I try this route as maybe my last chance to fix this thing. I will condense as much as possible, as it's really long. We are all totally baffled as to what is causing my 2000 C5 to not run for more than 10 minutes!!!!! I bought a seasoned LS1 block from SDPC 2 years ago. Steve@ Race Engine installed Darton sleeves. W2W built the motor, and it has a Callies 4" stroke crank, making 427 cubes. Allan Futral custom ground a cam for it, and it has CNC'ed AFR 225's, It has the Callies/Compstar rods, Diamond forged pistons, Total Seal gapless rings, Cometic head gaskets, Smith Bros. pushrods from W2W- all good quality stuff. W2W had the car for over 6 months trying to fix/diagnose it and....they actually told me it is the first car they can't fix!! After about 10 minutes of running time, or a coolant temp of about 180-186 degrees, it throws a code, a p0336, if memory serves. What I DO REMEMBER FOR SURE is that according to my Diablosport hand held tuner/scan tool, it says a "Crank Sensor Circuit Failure". This motor ran fine until it hit the 30,000 mile mark. This happened with no prior trouble AT ALL!!!W2W tried a Big Stuff 3 w/it's own separate 12 volt power supply and wiring harness, isolating my C5's wiring totally. No change-after about 10 minutes, it tripped the same code again. As a last resort, they had some guys from G.M.'s Tech center come in, and they believed the problem was mechanical, NOT ELECTRICAL. That said, W2W hooked up an oscilliscope to the crank sensor circuit and fired the car up (it always starts and runs great- until the coolant reaches 180 degrees, or about 10 minutes). When the car threw the code (like it ALWAYS does-for the last 9 or 10 months, anyway), the oscilliscope's waves were NOT affected. After waiting until the next day, thereby letting the motor cool down completely, the hooked the oscilliscope up to the cam position sensor. When the car tripped the code again (Old Faithful-DAMN!!!!), BINGO-the scope went banannas!!!! Since new/different sensors were tried numerous times, they figured that it had to be something internal in the camshaft-thermal expansion related, somehow, someway. After they pulled the cam, it has one scored lobe-the very first one back from the timing gear. Everyone says that this SHOULD NOT be affecting this motor THIS DRASTICALLY. The bad lobe is but .005-.010 deep, and the lifter looks good. The oil pan was yanked to check the reluctor wheel positioning, but all was well (As a sidenote, W2W felt that IF the wheel was moving around, it wouldn't run as well as it does for the first 10 minutes!! And eventually, it would move enough to NOT run at all.) As long as the pan was off, they checked the crank thrust, as well. It checked O.K., too!!!!! I have ordered a new cam and lifters, and plan on, I hate to say it, re-install the problem. I am hoping that it is somehow the cam being scored, but I don't think this is it either. This block's an early LS1 block and Steve@ Race Engine says he has heard of a problem with some of the early LS1 blocks not having the crank sensor bore deep enough, thereby keeping the sensor too far from the reluctor wheel. But why did it run so great for 30 thou and all of a sudden-junk??!?! And the guys at W2W said it was the cam sensor that sent the oscilliscope berserk. HELP-I can't even drive my car, for the last 10 months!!! And I sure as hell can't/wouldn't sell it like this!!! Have any of you guys EVER heard of anything like this??? Guys, you are my last hope! Please help me. Even if someone does manage to help get it to run for longer than 10 minutes, can I ever trust it again?? It might go for 2 or 3 hours-then quit again. I had just got back from California when this happened to it about a month after getting home!!!! What if it happened while 2500 miles from home??!!! Words can't express how awful this whole thing has been. Please-if anybody can help, let me know. Thank you.

WizeAss

iTrader: (5)

location might help if someone is close by??

Z28FirefighterI1

iTrader: (16)

Hey just had the same problem with my new motor but mine only ran good the first 25 miles after that if it was cold, it would run great till the temp hit 180 it would throw a p0336 code and run like ****. Let it cool down all the way and it wound run good again. I tried everything and six weeks later I pulled the motor. My motor builder found the crank had walked. After he rebuilt it again the motors in and running great. Try pulling your balancer back and forth, if it moves at all somethings needs to be checked out. I think it needs only like 4 - 7 thousandths crank play. Good luck...

WS6NIGHTMARE

iTrader: (7)

Man this sucks! I dont really have a suggestion for this problem. Im just going to subscribe in the hopes I learn something new here.

cablebandit

iTrader: (37)

relucter wheel is only allowed .020 runout i think it is

Stang's Bane

iTrader: (22)

I think this may be your problem. Once your block heats up and expands it moves the sensor to far from the crank.

Just a stab in the dark.

Also it may be a combination of problems not just one.
Like I said, just a shot in the dark.

helicoil

iTrader: (104)

If that is the case, you should see the CKP waveform drop out right before the car dies.
Honestly, if it is occuring that regular this should not be that difficult to fix. Someone with a good DSO that can capture the 'die out' should be able to pinpoint WHY it is dying. Now the cause could be a little more difficult.
Do yourself a favor and get a factory service manual and look up the DTC P0336 and look at the conditions to set. Then focus in on these areas.

It could be something such as too big of an air gap at the CKP reluctor on the crank due to block expansion, it would be unusual, but possible.

Also, CKP reluctor run-out should be checked. Not an easy thing to do, but with the code and all of the aftermarket stuff - a DEIFINITE.

The 12 volt reference and ground should also be checked to the CMP and CKP. Be sure and check them under a load, not just for OPEN circuit voltage, or potential.

Try and take some clay and smash it between the CKP and the reluctor wheel when the block is hot to get an accurate air gap measurement. You may have to modify the CKP to get it to sit deeper in the block.

If the CKP reluctor has excessive runout, this should be able to be seen on the CKP waveform with the DSO hooked up to it. It wouldn't be as easy as with a VRS/magnetic pulse generator but should still be there with the MR/ magneto resistive sensors.

I'll do a little searching through my folders, I did some write ups on this Gen III ignition years ago. They are all the same until the LS7 stuff rolled out.

Good Luck, get the service info, golden!

helicoil

iTrader: (104)

Going from memory a DTC P1336 means the Crankshaft Position Variation ReLearn has not taken place. This must be a Scan Tool initiated command to tell the PCM to learn the relationship of all the NEW components. It normally consists of a rev to fuel cut-out in Park alowing the PCM to learn the characteristics of the CKP on decel. Fuel-cut can be 4500RPM or higher if I remember, never liked doing them on Brand NEW engines, but a must to avoid a P1336 (1 represents a manufacturers code). Is it there?

Have you searched for GM TSB's (Technical Service Bulletins) and does your PCM have the latest GM calibration in it for your vehicle?

quikz

iTrader: (7)

Here is some info for people to view to help diagnose. I bolded an interesting cause for this code. Is it possible the engine is stalling and the code is not the cause for the stall but rather a byproduct of it? I realize the car may not be stalling as described in bold but if something weird is causing the stall this could still possibly happen. Is the stall quick or more violent(engine shaking badly)?


The following conditions may cause this DTC to set:

- Poor connections Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
- Crankshaft reluctor wheel damage or improper installation
- The sensor coming in contact with the reluctor wheel
- The engine running out of fuel
- If the crankshaft rotates backwards, this DTC sets. This condition is only with vehicles equipped with a manual transmission. This condition occurs when a vehicle is on an incline and the clutch is released and an engine stall occurs.
• Excess crankshaft end play will cause the CKP sensor reluctor wheel to move out of alignment with the CKP sensor. This could result in any one of the following:
- A no start
- A start and stall
- Erratic performance
• An improperly installed propeller shaft could cause excess crankshaft end play.

Visually/Physically inspect all circuits going to the Crankshaft Position sensor for the following:
- Routed too close to secondary ignition wires or components
- Routed too close to after-market add on electrical equipment
- Routed too close to solenoids, relays and motors

Vertical lines across the face of the sensor could indicate foreign material passing between the CKP sensor and the reluctor wheel. Non vertical lines across the face of the sensor may indicate a crack in the CKP sensor. Either of these conditions causes this DTC to set.

Stang's Bane

iTrader: (22)

I am going to have to take your word for it, because I have no idea what the hell you are talking about