Lately I have been having some crazy Timing drops while cruising at highway speeds. I have logged the car with HP tuners and when cruising down the highway at 75 miles per hour. The car will be showing 25 ish degrees of timing at highway speeds with cruise engaged. When all of a sudden it will suddenly drop from 25 degrees of timing to 3 or 4 degrees of timing for no reason. And I can feel the Loss of timimg in the seat of the car. You can feel it fall on its face. And then all of a sudden it jumps back up to 25 ish degrees again. Then drops again repeatedly. My hp tuners log shows the drop in timing. I have watched the cam angels in hp tuners. And they seem to stay fairly steady. But they do fluctuate a bit . About 1 to 2 degrees. My primary 02 sensor reads a fairly constant reading. I'm at a loss to think of what could cause a loose of timing like that at highway cruising. Also , when accelerating in each gear. If I take it up to 4k and then shift . When I give it some gas after shifting it won't accelerate at all for about 2 or 3 seconds. The turbo boosts. I can hear it build boost. But again , according to hp tuners the spark is at 0 degrees for a few seconds. And then all of a sudden it returns to normal and then accelerates normal for the rest of the gear.

Wot appears to be unaffected at all. As well as if I totally baby the car it is 100 percent normal. Its only under the more normal driving loads it is dropping timing.

hp tuners is not showing me any problems other the the total loss of timing. The cam Acuaters ( The two that side uptop of the valve cover that stick straight up. ) are only 6 months old. The car has zero codes. And ideas???

 

I just cleaned my intake valves and got fresh new plugs with a new gap and this fixed my timing issues. Does HPTuners show any misfires during this? Thats what I had.

 

Valves where just cleaned in November. Ad well as new plugs. There are no misfires at all in hp tuners. It is deffinitly a big drop in timing. Totally random. At cruising speeds on the highway and just after I shift as I first press on the gas.
Zero codes .

 

Valves where just cleaned in November. Ad well as new plugs. There are no misfires at all in hp tuners. It is deffinitly a big drop in timing. Totally random. At cruising speeds on the highway and just after I shift as I first press on the gas.
Zero codes . What controls timimg in an Lnf other then the cam phasers and actuators ?? Thanks

 

There is the Camshaft Position Sensor that sits close to the front of the car. After consideration of my issues, which I'm getting my valves cleaned next week, is to check fuel rail pressure, injectors, and maybe even your fuel filter. In my GT (N/A), I had this issue, but also a small fuel leak centred above the fuel tank. After I had the lines, pump, and filter replaced, I didn't have an issue until my MAF got dirty.

 

False knock would cut the timing. Are you logging knock when logging? If so, I would add that to your list. Post a log file when its acting up if you can.

 

I have a log file. I will post it in a few minutes. The log shows no knock when the timimg is dropping. I do het some burst/ tip in knock as some wouod call it when I first hit the throttle. But nothing much at all. But my timing drop is near removing 20 dehrees of timing. Way too much for false knock. If it was seeing any. But the logs don't show any when it is happening at highway speeds and a steady throttle at about 2800 rpm.

I will post the log soon. Hopefully you can see something I am missing.

 

Log 1

 

Log 2 Look at time frame of 6 minutes and 13 seconds to about 6 minutes and 20 seconds. The speed uptop in thee log will show about 70 miles an hour at a constant 25 to 35 ish percent throttle when the timing drops on both logs.

 

You need to log more stuff. Thats limited info you posted. Maybe @ECaulk can send you his log channel list which would greatly help out.

 

That would help for sure. But what else should I be logging and looking at to see what is casting the 20 degree drop in timing at cruising speed on the high way ? What channels are missing that I could or should be adding ?

Thanks

 

Use this. I've been working with ECaulk on my tune lately.

 

Thanks , do you have a specific LAYOUT file for the channels config as well ?

 

If you're talking about the gauges, I left that as default on my setup. I just have the channels.

 

You can probably adjust the MAP gauge to not go to 110 psi. Same for the MAF, no need to display up to 60 lbs/hr. 40 lbs/hr should be good enough for a stockish turbo LNF (I assume).

I customized my gauges to just display the MOST pertinent of information that I want to look at in a flash, with it showing peak values for things like RPM, boost, MAF flow, and knock.

You can obviously remove all the Bank 2 stuff, since that doesn't apply.

 

I know the ecu controls timing based on input from several sources. But does anyone know what else to look at other then the Cam solenoids , Cam sprocket phasers and the cam position sensors ? The cam sensors and the cam solenoids are all new. Im just wondering what else the ecu can see that would cause a 20 degreee drop in timinig with no misfires and no knock at all when it is happening. Thanks

 

What is your engine load doing when the timing drops?

Does the timing drop match a decrease in throttle position, like letting off on the throttle a bit?

If I can remember when I get home I'll post up my channels that are a little different than what Prof posted, we had some issues getting my channels and layout to load on his hptuners (I may have saved them in an older version of vcm scanner).

 

40lb/min is safe, you're not getting that flow reading unless your maf is way off (like 10-20% off)

 

If I remember right, I think he was at like 35% TPS and would drop to about 32% when timing started to pull. It was a slow ramp down.

 

I posted a few logs that i did do with a few channels on them. The car is at highway speeds. At about 30-35 percent throttle on flat ground. And then the throttle stays farily constant and the timing just drops to pretty much 3 or 4 degrees instead of the usual 25 ish.. At wot the car is fine. up hills is fine. decel down hills is fine. Its only on flat ground it seems to fall on its face. if i give it more throttle it seems to be fine. But steady state as well as JUST a second or two after i shift Those times it will act up. After shifting about 2 seconds later the timing jumps back up to normal and the car acts fine until i shift again or it is at say 2800 rpm or above then it breaks up for a second. Wot is fine. Any help you could give me Ecaulk would be much appreciated. Thanks

 

I'll try to take a look at your log later tonight, the timing drop like that sounds like something is triggering a torque demand drop. If I see something strange I'll post in here about it.

 

Thanks... I appreciate it a lot !!

 

This doesn't necessarily rule them out. There's an infant mortality rate for electronic components, so something failing out of the box or soon after would not be that unheard of.

How much tuning has been done on the car recently? By you or others? Have you done a file compare with a known good file or stock/GMS1 file to see if something got (accidentally) changed somewhere?

Odd thought... maybe check the clutch switch/switches? Is it activating (thinking the pedal is being pushed) and pulling timing? The event occuring after a shift makes me think that might be happening. Although it's odd that it only otherwise happens during steady-state cruising. So maybe it's not that... but might be something to keep in mind.

My bottom switch acts weird occasionally and won't let me start the car.

I figured as much, but haven't logged one, so couldn't say for certain.

 

Can't tell much from the log, but it looks like it does it when you're using cruise control (accelerator pedal at 0% but you're not in DFCO).

Have you touched the optimum spark tables/MBT tables?

Do all your main spark tables have the same value? Under the base heading in spark

Also lean out your PE, LNFs like it lean. If you're super concerned run a lambda of 0.86, but I normally run 0.88 without issue.

Additionally do a compression and leak down test, you are showing some KR at high loads, but without looking at your tune it's hard to say if its just the ecu being pissy or if its actual KR.

Try getting a log with the channels attached to this post, this one should have everything you want to log (haven't connected this computer to my LNF and my normal tuning computer's battery is dead and its a slow beast from dead battery restart).

 

i will re log it again tomorrow with your channels. I have not touched the Optimum spark tables at all. BUT i have changed a few of the values in the left hand side of the spark tables at low loads in a few cells. Maybe that is causing it to go haywire, . Maybe I should revert back to a tune from a few months ago and see what it does . The compression on the car is decent for its age. it has 158 ISH psi in all for cylinders. She is an old girl. It has been my daily sense 09 when i bought it brand new. It has 200,000 Km on it, about 125K miles or so. It still pulls hard. And spins all of second. I haven't done a leak down. And i probably won't. As I'm sure it will show a bit of wear. Lol... I have another LNF from a 2010 that is very low miles that I will put in next summer.. I'm just looking to solve my timing drop issue atm. As for the Lamda . I am running Meth. I use a #3 nozzle on a devils own meth kit. My lamda in hp tuners only shows the 50 , 60 ,70 ,80 colums. The 80 column has a lamda of .85. If that seems good ? Or is that too rich running meth and I should change the 80 column to .85 like you were saying ?

As for the knock. Im pretty suire it is all false and ghost knock. and a bit of tip in knock. Its an old motor. But still works well. and pulls hard. When I first logged it near brand new with hp tuners on GMS1 and everything else stock it had 4 degrees of kr. Anything lower then that, I dont worry about. Lol... In Canada 91 octane is the best we see hear.

I will revert back to an older tune file that wasnt changes as much inj the spark cells at low load and see what it does. My other big question is what should I have that 80 column at for the Lamda when running meth ?

Thanks

P.s- Log to come tomorrow,