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Chevymanzz572
03-11-2011, 22:43
hi i have a 96 chevy with the 6.5 that ran good when i bought it, it ame with the number 9 resistor and a new pmd i installed a 3'' mandral bent downpipe and an intake and rerouted the blow by gasses and it ran fine for about a day then it started throwing the p 1214 tdc offset code i try to reset it with a gm tech 2 scan tool and im not quite shure how you would with the tech 2 does anyone know how with the tech 2? also i was wondering why it would all of the sudden start doing it when all i did was install these pieces and unhooked and rehooked a ground on the battery but made shure it was clean and had a good conection when i reinstalled it. i have tried the method where you hold the petal for 45 seconds then shut the key off for 30 and it doesnt work i have tried it at least 5 times following all the steps can anyone help me thanks

suburbanK-2500HD
03-11-2011, 23:51
Do you have an email adress, i can send you the prosedure.

Chevymanzz572
03-12-2011, 07:04
yes its cooter3890@yahoo.com

racer55
03-12-2011, 12:28
From what i have read and tried myself,the tech 2 has trouble with TDCO on the 96`s,select 98 or 2000 as the model year and it will work much better.

JohnC
03-13-2011, 08:45
If the TDC offset is wrong and you don't adjust the pump, it'll just continue to set the code each time you start it.

omoige
07-15-2014, 01:26
hi i have a 96 chevy with the 6.5 that ran good when i bought it, it ame with the number 9 resistor and a new pmd i installed a 3'' mandral bent downpipe and an intake and rerouted the blow by gasses and it ran fine for about a day then it started throwing the p 1214 tdc offset code i try to reset it with a gm tech 2 scan tool and im not quite shure how you would with the tech 2 does anyone know how with the tech 2? also i was wondering why it would all of the sudden start doing it when all i did was install these pieces and unhooked and rehooked a ground on the battery but made shure it was clean and had a good conection when i reinstalled it. i have tried the method where you hold the petal for 45 seconds then shut the key off for 30 and it doesnt work i have tried it at least 5 times following all the steps can anyone help me thanks


I am having this same problem right now and very confused as to what to do next. I changed my PMD to a brand new one with the #9 resistor. Located it outside of the engine. Car runs great but throws code 1214. Used Tech 2, it shows -2.46. I adjusted the IP all direction severally, no change. I am looking at possibly the Crank position Sensor. Please help. Mine is a 2002 Hummer H1 with 6.5TD. It smokes only when I had pedal. And it is black.

racer55
07-15-2014, 04:44
Every time the IP is moved the engine needs brought up to temp and a TDCO relearn needs to be done to find out the new IP timing location with the codes cleared.

Once you get the IP in the proper range the offset code will stop happening.

My suggestion would be to run a TDCO relearn again and adjust as needed.

omoige
07-15-2014, 11:01
I have done the relearn several times to no success. I am not sure I know what I am doing or something is wrong with my IP. Important question that I have is this: Will this damage anything if I keep driving the truck like that? The car runs excellent with know issues other than the Check Engine Light that is constantly on.

racer55
07-16-2014, 07:06
The codes must be cleared to get the relearn to take,so you must be very fast at clearing the code and starting the relearn before the code resets.
temp must be 170F +.

I am suspecting a faulty/aftermarket CPS is part of the trouble?

Kennedy
07-17-2014, 09:14
Start with a Time Set procedure that commands the timing to 0. It should be at or around 3.5° but of course will fluctuate.

Right now the pump is a bit advanced and is off the scale/out of range. It needs a very slight rotation to the passengers side. As mentioned above clear DTC and relearn. Relearn will NOT go if ECT drops below 170°f so you may think you are doing the learn, but it is not.


Another test for the stepper motor is to change engine speed so that desired increases above actual and verify that actual moves to follow. I'm not sure if it will do much of anything with a DTC present though.

omoige
07-17-2014, 10:31
Thanks guy, I will get in the engine bay this weekend and do the rotation toward the passenger side. Then I will try the relearn again. I want to know from you expert out there, Is it ok to drive it like this while I am still figuring out the solution? Or do I risk doing any damage to the engine by driving it like this? Thanks

racer55
07-17-2014, 11:31
not sure about any dammage?

Small movements of the IP make a big change so a 2mm movement towards the passenger side will likely get it back in range to get a valuable TDCO reading-adjust from there if required.

Kennedy
07-17-2014, 12:09
To the best of my recollection when the TDC offset is out of range it sets the DTC and puts the timing into a pretty flat and safe range.

omoige
07-17-2014, 20:48
Interesting Kennedy. Thanks for the peace of mind information. It is relaxing to know that. I will get to work tomorrow and let you know how far.

omoige
07-20-2014, 12:32
Ok guys, I think I got it fixed. I moved the IP toward the passenger. I checked Tech 2, it came up with error code P0219 while TDC Offset was at 2.46 at this time. Then everything went haywire. Smokes all over the place. Now it is no longer black smoke, but bluish white. I didn't even try try the relearn process. I quickly shut the engine and loosen things up again. I returned the IP halfway from where it was. Then, the code went away, but Tech 2 gave an offset of 1.46. I wasn't sure what was going on. All the same, I tried the relearn process. For the first time, my Tech 2 actually made me happy for the money spent. The TDC is now at .97. No more codes. Is this acceptable guys?

Kennedy
07-21-2014, 13:33
Depends how good you want it to be. If you could nudge the pump ever so slightly to the drivers side and relearn should get you closer. Repeat until you hit -1.94

Once you have the hang of it the task is quite simple. I forget how many I did out at Bigley's during the 2000? Rendezvous but it was multiple.

omoige
07-21-2014, 19:03
Depends how good you want it to be. If you could nudge the pump ever so slightly to the drivers side and relearn should get you closer. Repeat until you hit -1.94



Now I am a little confused. Am I shooting to get the TDC to -1.94 before the relearn? Or is that my final destination after the relearn?

DmaxMaverick
07-21-2014, 22:57
Now I am a little confused. Am I shooting to get the TDC to -1.94 before the relearn? Or is that my final destination after the relearn?
-1.94 is the final destination. After the final relearn.

omoige
07-22-2014, 01:58
Thanks, Now I know what I am shooting for

omoige
07-22-2014, 10:46
Hey guys, this is frustrating. I kept adjusting and adjusting back and forth. It kept bouncing back and forth between numbers. My final best result so far is at -1.41, Is this okay to leave it alone. I have tried more than 50 times, this is the closest I got. Or is there an easy way to getting on the mark of -1.94? Please help.

DmaxMaverick
07-22-2014, 12:30
-1.41 is fine. Some engines aren't able to reliably set -1.94, often due to a sloppy valve train. Easy to get with a gear set or new timing set, and/or new pump, not so much with worn chain/sprockets or a well-used pump.

omoige
07-22-2014, 12:56
DmaxMaverick, your response is a breath of fresh air, so relaxing. Thanks so much. I am almost tearing off my hair.

I am still having black smoke though. Will this clear away with time now that I am somewhat close to the engine running perfectly. I mean, the engine is so smooth running I could drive with my coffee mug on the hood without spilling it. so far, running at idle without smoke, but when I step on it, it puffs smoke, though not as bad as when I started out when it was -2.46 TDC

DmaxMaverick
07-22-2014, 13:57
A puff of black smoke on hard acceleration is normal. The 6.5L fuel delivery, unlike later Diesel engine designs (Duramax, etc.) are not dependent on air volume. If the smoke continues after the turbo spools up, you may need to look a bit closer at that end of it. A fouled air cleaner will also cause the same thing.

Kennedy
07-22-2014, 14:19
Once you are close you can keep on initiating the process until it hits on your number. To get to -1.94 you'll need a c-hair of a nudge though.

You're OK where you are though too.

omoige
07-22-2014, 18:31
Thanks a lot Kennedy. I am just going to leave it here since you guys, in you prowess of knowledge, have assured me that this is just fine. It took me endless trials to get to this point.

All the same, I will try using the Tech 2 to keep trying to relearn to see if I can get lucky to get it there. I am so grateful for your contributions here. I wouldn't know what to do not for this forum.

omoige
07-30-2014, 14:46
Once you are close you can keep on initiating the process until it hits on your number. To get to -1.94 you'll need a c-hair of a nudge though.



Hey what do you know. I kept re-initiating the re learn process. I am now at -1.58.
Please guys, explain something to me. When I am driving this hummer, usually go about 60 miles average, the temperature is always on the third quarter borderline line. That is the next after the middle line. However, once I either slow down or standing still, idling, it goes down to just a notch to the other side of the middle line. Since there is no number on this temperature gauge like my Japanese cars, I am not sure if this is ok or running hot. Please educate me.

DmaxMaverick
07-30-2014, 15:02
Hey what do you know. I kept re-initiating the re learn process. I am now at -1.58.
Please guys, explain something to me. When I am driving this hummer, usually go about 60 miles average, the temperature is always on the third quarter borderline line. That is the next after the middle line. However, once I either slow down or standing still, idling, it goes down to just a notch to the other side of the middle line. Since there is no number on this temperature gauge like my Japanese cars, I am not sure if this is ok or running hot. Please educate me.

It's hard to say. In order for a gage to be accurate, it must use the sender it was originally designed to be paired with, and it has to be accurate to whatever standard accepted at the time. Having numbers on a gage will not make it any more accurate than a gage without, unless you know what the needle positions actually mean, and many aren't even linear, or are only accurate within a very specific range. Ford's historical H-C gage is actually better in this regard, in that it only indicates an operating range, and not some obscure number that means nothing to the vast majority of the population. Ultimately, instrumentation is only effective for tracking trends. Once you know what is hot enough, and not too hot, you only need to watch that it doesn't exceed those limits. The same applies to any other instrumentation.

Solution....
Install a new mechanical temp gage and watch it, and compare it to the OEM gage. Anything less will tell you nothing more than you already know.

omoige
07-30-2014, 15:15
[QUOTE=
Solution....
Install a new mechanical temp gage and watch it, and compare it to the OEM gage. Anything less will tell you nothing more than you already know.[/QUOTE]



That's a great idea. I never thought of that. I will shop around to get a VERY good mechanical gauge and see how it differs. However, because this is my first diesel truck, and a a hummer H1 for that matter, I have no idea what is the normal operating range on this needle style gauge. If I have to relate it to my Toyota FJ Cruiser or my Porsche Cayenne S for instance, it is already over-heating. What gave me peace of mind was the last time that I connected my Tech 2 after just coming back from one a hell of a grueling ride in the jungles. While I was thinking that the engine has seen some serious abuse, the Tech 2 reported that my temperature was too low to do a relearn. I have driven this car for the past 5 hours through grueling coastal jungle and I thought I have overheated it at some point. Anyways, I am learning as I am going along. And with all the experienced hands in this forum, I have GREAT mentors to fall back on. I am beginning to like the sound produced by my diesel too.

DmaxMaverick
07-30-2014, 15:49
You don't need to know, yet, what the normal operating range is for that gage. That is what the mechanical gage will tell you. You will also need to know what temp the thermostat is, to determine if it is doing its job. Replace it with new, if you don't know. Get a new stat from the dealership (Delco ONLY), or from Kennedy. Any others are substandard junk that won't work if you work your truck hard. To round off the equation, you'll also need to know if the fan clutch is engaging, and holding, when it should. A lazy fan clutch will make all your efforts moot, having no way to manage high load temps. Your Hummer H1 may have a hydraulic fan clutch, which allows for much more flexibility. If not, installing one would be a significant upgrade.

omoige
07-30-2014, 22:31
Hmmm, must have done something wrong. I just ordered new set of thermostats from Rock Auto. They should be arriving in a day or two. They are the Motorad brand. My Hummer uses 2 in a row. Do I have to return them? For the fan clutch, when the engine temp gets up, I know it works because the sound changes to something heavier from under the hood. And as soon as the temp goes down, it goes quieter.

Also, I noticed something that is rather strange (to me, of course)earlier today when I was cleaning the engine. I removed the PSD with the #9 resistor and put one without the resistor. I started the engine. At first it was running great, then suddenly, it started to accelerate weirdly up and down. Then I put the old one with the resistor back. Everything went back to normal. Then I removed the resistor from the old one and connected it back, it started running weird again. As soon as I inserted the resistor back and connected it, everything went back to smooth idling. Is this normal? Does that mean it must have the resistor to run? Or is this resulting from the relearn process I initiated, because I did the relearn with the resistor in the PSD. PLEASE educate me.

DmaxMaverick
07-30-2014, 23:02
The resistor is necessary, or the PCM will have a fit. The #9 may be your problem, as some PCM's don't like it, or don't like it in combination with your pump, more appropriately. The resistor is a "calibration resistor", which does nothing more than communicate to the PCM the calibration range of the pump, and some are out of range with a #9. In any case, increasing the resistor number can increase power, but you'd really need a dyno to notice it. It isn't like turbo boost on KITT. I'd be very surprised if you were able to do a TDCO learn with it removed. The Sol-D is the only FSD I know of that doesn't require a resistor, and they aren't common lately.

The dual thermostat is an excellent option, and probably not part of any of your problems if they are working. The pair you got from RA is probably OK, if they're the correct temp (2x 195, or 195 + 205), lower is not better, if the rest of the system is healthy, but the high capacity water pump is necessary to take full advantage of it. Cooler stats doesn't do anything but lower your threshold, and won't allow for more loading. Just something to keep in mind. The cycling fan clutch is good, as it indicates it's active when it should be. The stat(s) control when the fan clutch engages, most people don't know that. The hydraulic clutch, if you have one, or a Kennedy clutch is ideal, as they engage more positively (aggressive), when they are engaged.

omoige
08-01-2014, 01:36
The resistor is necessary, or the PCM will have a fit. The #9 may be your problem, as some PCM's don't like it, or don't like it in combination with your pump, more appropriately.



Now I get it!! I am on my 3rd FSD. The truck came with the Standard FSD. Because the car was running rough, I bought a used Stanadyne PMD. It didn't help the situation. They I bought the brand new grey Stanadyne with all the relocation kit. That one came with the #9 resistor. He gave me the option of either #5 or #9 when I was buying it after I explained my problems. As soon as I installed, it was running great. Then the code P1214 came up. But since I cleared the codes with helps from this forum, I have been having fun as the car has been a great runner with the exception of trying to get it on the -1.94 dot. Should I change the resistor to #5 then?




The dual thermostat is an excellent option, and probably not part of any of your problems if they are working. The pair you got from RA is probably OK, if they're the correct temp (2x 195, or 195 + 205), lower is not better, if the rest of the system is healthy, but the high capacity water pump is necessary to take full advantage of it. Cooler stats doesn't do anything but lower your threshold, and won't allow for more loading. Just something to keep in mind.

Dmax, please elaborate on 2 points you raised for me here. You wrote that "lower is not better" I may be wrong, I usually think that lower means lower operating temperature. Have I been wrong all the while? By the way, stats I ordered are both 195s. Secondly, How do I know if my truck has the high capacity pump? Doesn't this model come with it anyway, since the 2 thermostats are factory installed to correct overheating problem from previous models. Thanks again for your responses. They are really educating me.

DmaxMaverick
08-01-2014, 10:52
Now I get it!! I am on my 3rd FSD. The truck came with the Standard FSD. Because the car was running rough, I bought a used Stanadyne PMD. It didn't help the situation. They I bought the brand new grey Stanadyne with all the relocation kit. That one came with the #9 resistor. He gave me the option of either #5 or #9 when I was buying it after I explained my problems. As soon as I installed, it was running great. Then the code P1214 came up. But since I cleared the codes with helps from this forum, I have been having fun as the car has been a great runner with the exception of trying to get it on the -1.94 dot. Should I change the resistor to #5 then?

The P1214 isn't related to the resistor. Just a note, but the resistor is located in the PMD connector for no reason other than convenience. It has nothing to do with the PMD. Stanadyne put it there, apparently, because it was just as good a place as any. The purpose of the "calibration resistor" is to compensate for slight variations from pump to pump. The PCM only reads (checks) the resistor periodically, so if it's one it doesn't like, or is missing, it may be several warmup cycles before it actually notices. P1214 is the PCM complaining that it can't compensate the TDCO, because the pump is out of physical range (in your case), or some other reason. Even if you manage to get it at -1.94, the PCM may fault at a later time due to valve train variations (sloppiness), usually more common on higher mileage engines.



Dmax, please elaborate on 2 points you raised for me here. You wrote that "lower is not better" I may be wrong, I usually think that lower means lower operating temperature. Have I been wrong all the while? By the way, stats I ordered are both 195s. Secondly, How do I know if my truck has the high capacity pump? Doesn't this model come with it anyway, since the 2 thermostats are factory installed to correct overheating problem from previous models. Thanks again for your responses. They are really educating me.

Lower is not better, in that, a reduced operating temp (below OEM) is not, necessarily, better.
If your engine is stock with the dual stats, it will (should) have the high volume water pump. A pair of 195 stats is good. A lower operating temp is not good, as it reduces combustion quality, and metallurgic variations are less consistent. The only reason to lower the operating temp, by any means, is to compensate for an inadequate cooling system. If your system is healthy and able to manage high load temp ranges, higher is better. Most cooling systems are very good when new, not so much as age and miles add up. Unfortunately most of the time, engineers don't design too far down the road. Regular maintenance is the key to keeping a system healthy.

omoige
08-01-2014, 15:28
I am glad I discovered this forum. I am a great example of how what you don't know can hurt you. I was already thinking on researching how to get the 6.5L Turbo Diesel engine in my H1 to run cooler.

Thanks for all these priceless information.

DmaxMaverick
08-01-2014, 15:56
I am glad I discovered this forum. I am a great example of how what you don't know can hurt you. I was already thinking on researching how to get the 6.5L Turbo Diesel engine in my H1 to run cooler.

Thanks for all these priceless information.

Well, there are several schools on this. A reason to want to reduce the operating temp, as I said before, is an inadequate system. A system inadequate for any number of reasons, including old, failing and in need of significant repair, or added load on an already marginal system. The solutions are simple, although often not inexpensive: Repair/replace as necessary; or increase cooling capacity and/or efficiency. If you aren't having uncontrollable overheat issues, what's to worry? If it ain't broke, don't fix it.

omoige
08-01-2014, 17:44
If you aren't having uncontrollable overheat issues, what's to worry? If it ain't broke, don't fix it.


You got that right buddy. Truck has only 66,000 miles on the odometer and runs like a champ. I'll just keep it that way for now. Once I learnt more tricks from guys like you in this forum, I may stat to alter things.