need help on 99 5.7 timing and p1345

I changed the intake gaskets and I got the distributor in exactly as the book says. Engine runs but reports P1345.

Scan tool shows timing advance at 22 degrees and engine idles nicely after an initial correction.

I don't think the distributor is off a tooth because the rotor aligned with the "8" which is also number 1 tower and moving one tooth would change the timing over 40 degrees.

I have the Dyno-Scan by Auterra and I cannot read the camshaft retard offset adjustment. Should any consumer scan tool pick this value up? I'm disappointed that the dyno-scan doesn't.

Do you think I'm close enough where I just need an adjustment? or is the distributor in wrong? I don't see how I could be a tooth off and the engine run so nicely.

Thanks in advance for help.

skimmer

Reply to
News Skimmer
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Bummer...

The P1345 has absolutely nothing to do with ignition timing.

The code definition for P1345 is; cam position sensor is not correlated with the crankshaft position sensor. IOWs, it is not synched as close as it should be. I DO think the distributor is off one or more teeth, and no, changing the distributor will NOT change the ignition timing one degree or 40 degrees. The distributor only performs two jobs;

1) It distributes the ignition secondary to the proper plug wire 2) It holds the camshaft position sensor whose job is to sequence the fuel injectors and has no role in ignition timing. The camshaft position sensor does not function as a set of breaker points or a pole piece/timer core -used to-.

Don't know whether consumer grade scan tools will or won't read camshaft sensor offset. Best thing would be to call Auterras' tech support and ask them if it can and where that PID is located in their menu.

No way to tell until you can actually read the number of degrees the CPS is offset. And, until you know how many degrees plus or minus, you will not know which way to turn the distributor to get it synched back up. Be advised, the engine RPM -has- to be raised above 1000 RPM for the CPS offset PID to update.

Only two things are effected if the distributor is installed a tooth off;

1) cam position offset (which shows up as a P1345) 2) Rotor to cap air gap (which can only be detected/observed by scoping the ignition secondary)

The other thing I would do is; get a small mirror and flash light and check the terminals in the plug on the camshaft position sensor to see if any have been bent over, I've seen this more than once...

Reply to
aarcuda69062

There is no cam posotion sensor per say. THey have simply renamed the magnetic pickup in the distributor the CMP. It is not any where near the camshaft otherwiise (distributor is driven by cam). A P1345 usually can point to a bad CKP (crank position sensor) which provides baseline timing referance together with CMP. CMP or distributor pickup errors are usually a P0340 or P0341. If either of these sensors are eratic it can cause timing issues. BTW, 22 BTDC idling warm is quite normal so do not make a big deal out of it.

----------------- TheSnoMan.com

Reply to
SnoMan

Cuda...thanks for your help. I know it takes time to respond.

I'm going to look into the Auterra biz. I'm not satisfied with that thing at all. Will contact Actron as well.

One thing I will try tonight is running the engine above 1000 rpm. I've been starting the truck from the passenger side and have never pressed the throttle. Maybe it just needs to reset....but probably not.

Will also check the plug as you say...but will have to wait until tomorrow.

skimmer

Reply to
News Skimmer

You probably should have informed GM of their error 10+ years ago.

It *is* a camshaft position sensor, that is why GM, Ford, Chrysler et al call them camshaft position sensors.

Being as it's output function is totally different than what was previously used, that is not a very accurate statement.

It doesn't -have- to be anywhere near the camshaft in order to be a camshaft position sensor.

Fuck context, eh? The OP just had the distributor out and the intake manifold off. If he had a failing CKP sensor causing a P1345, it would most likely have been there before he started working on the truck. Geez, you like to go off on tangents.

Again answering questions that were never asked...

Reply to
aarcuda69062

Auto Enginuity is also a PC based scan tool that I know for a fact will read the cam offset PID. The base program plus enhanced GM coverage will run you about $400 for hardware and software and is probably double what you paid for the Auterra, but it works well and has pretty good bi-directional command capabilities to boot. New basic Tech 2's can be gotten off e-bay for about $2700.00

Reply to
aarcuda69062

No it is not. Maybe you can call it a distributor cam sensor but there are other vehicles that have cam and crank sensors that do actualy monitor positions directly. Heck you could even call it a oil pump position sensor to if you wanted to because distributor drives oil pump too. It is strictly a play on words and misleading but it sounds more high tech than distributor magnetic pickup so they use CPS which is somewhat misleading because it IS in the distributor.

----------------- TheSnoMan.com

Reply to
SnoMan

Ummmm....Calling all SnoMan fanboys! This is a perfect example of why a number of us on this newsgroup have "nothing but disdain" for Snoman's supposed automotive knowledge.

Read it and weep!

Ian

Reply to
shiden_kai

You mean when logic exceeds your abilty you go to bashing and trolling right???. GM has used a magnetic pickup in the distributor since the days of HEI and they did not call it a CPS then. Same basic part and function today just a different name for it now and I am simply pointing that out. You guys are the one that is making something out of nothing as usual since you have nothing better to do and lack any real understanding beyond the very simple basics here.

----------------- TheSnoMan.com

Reply to
SnoMan

well said snowman old john

Reply to
<ajeeperman

You are stone stupid.

I can call it monkeys flying out of your butt, but it is still a camshaft position sensor. Besides, there is no "distributor cam" to begin with, so there is nothing to 'sense.'

Uh, don't look now Sherlock, but this one actually *does* monitor camshaft position directly. By your logic, the camshaft position sensor on a 3.4 liter DOHC engine isn't really a camshaft position sensor because it only monitors one of the four camshafts.

Really? What unique event occurs WRT the oil pump that we need a sensor for?

So WHAT if it is in the distributor? The distributor is directly synched to the camshaft (when correctly installed). The fact that this confuses you so, merely illustrates why you should be forever forbidden from giving any advice related to an automobile/truck/tractor/lawnmower/model airplane/Tonka toy/etc.

Reply to
aarcuda69062

It would be sad if it weren't so funny.

Reply to
aarcuda69062

They did not call it a CPS then because they didn't give a shit about the position of the camshaft. They used the pickup to determine the position of the crank/piston for ignition timing. As cuda said, the timing is still based on crank position ...now determined by a crankshaft position sensor which is a similar pick up looking directly at the crank instead of via the timing chain/cam/distributor gear.

The new CPS information is used to sequence the fuel injection. Since the crank position and cam position are related, the PCM performs a sanity check between the two sensors. Too bad it can't check your sanity.

The very simple basics have changed. Perhaps you should too or not reply to these posts.

Reply to
News Skimmer

Ian, you are spot on. Some of my previous posts requesting info....I ended the message with "snoman need not reply" or "no abominable answers, please".

Everyone....please forgive me not doing the same on my original post. I had no idea snoman would even read my message since it didn't refer to locking axles or engineering experiments from the 60s.

skimmer

Reply to
News Skimmer

Maybe because that magnetic pick up couldn't distinguish anything unique regarding the actual position of the camshaft relative to the crankshaft.

Uh, no, it isn't the same basic part. Someone with an EE "background" would know that.

The function is entirely different. Someone with an EE "background" would know that.

You point out too many things erroneously.

Actually, that was you. Looks like another case of Snojobs ego working the keyboard.

And your tips for the OPs code P1345 are/were?

Reply to
aarcuda69062

Well hot shot, let's hear your fix for the P1345. (or doesn't the sock puppet do driveability?)

Reply to
aarcuda69062

Great....you don't know the basics either! Which is why you are a Snoman fanboy!

Ian

Reply to
shiden_kai

I'm surprised that Snoman even chimed in! I thought Neil was doing a marvelous job of helping you out.

Ian

Reply to
shiden_kai

Thank ye!

Reply to
aarcuda69062

You know I pick and choose what I respond to because it is not about being shown up but rather not stooping as low as you do especail since I see that you posted 5 responces in a little over a hour in this thread. You must really be awfull insecure. I actually feel abit sorry for you and some of your cohorts at times because it appears that you may never grow up.

----------------- TheSnoMan.com

Reply to
SnoMan

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