Replaced Everything Still Long Starts!! Help Please!!!

atrussell129 · Oct 10, 2017

04 jetta tdi, 182,000 miles, new timing belt kit installed by deal 6 months ago but had starting issues before that. New in tank lift pump, new Tandem pump, and all new rubber hoses in engine bay. new Crank sensor, and grounded the wire for the crank sensor that always gets a short in it. New coolant temp sensor. New fuel filter without thermostatic T to eliminate any chance of air getting in line that way. I live in Florida so I never worry about cold starts. this also has a brand new battery.

Car takes a very long time and some time several cycles of cranking to finally start up first thing in the morning, I do not have this issue unless the car sits for about 5 or more hours. I am all out of ideas with what could be the issue.

Any help would be greatly appreciated.

Enabled · Oct 10, 2017

Is the cranking slow? (if you had something to compare it to)

atrussell129 · Oct 10, 2017

yes, I had a buddy send me a video of his and he has no issues with his and mine cranks at the same speed. If you have a video of yours starting I will also compare mine to yours. I also only get 36-38 mpg on running mainly highways running around 75-80 mph consistently. with tire pressure at 38 psi

UhOh · Oct 10, 2017

Torsion settings. Compression. (I'm not a PD guy, so that's as much as I can say here- just musing).

atrussell129 · Oct 10, 2017

I am moving in a few weeks and I will test the compression once I move. any idea where I can pickup a cheap computer to read the torsion settings? I have a laptop and a OBd2 dongle for my cell phone but I know I cant read any of that information with that.

Tdijarhead · Oct 10, 2017

http://forums.tdiclub.com/showthread.php?t=328868&highlight=pd+start+fix

Did you see this?

wonneber · Oct 10, 2017

Does the laptop have Bluetooth built in?
If so it should connect to the OBD dongle.
If not a USB Bluetooth adapter should connect to it.
VCDS Lite (http://www.ross-tech.com/vcds-lite/) will use it -IF- the BT adapter uses com port 1 to 4.

oilhammer · Oct 10, 2017

TSB referenced above, or another TSB for software reflash (which is of course obsolete anyway by now).

Tuners typically fix the long crank time when hot issue with software changes. Only the BEWs do that, the BHWs and BRMs do not.

However it sounds to me like you have a loss of fuel prime. I would try cycling the key a few times, when you know it will act up, then unclipping the thermo tee on the filter and make sure it is in fact fuel of fuel. I would also check the oil level in the engine and see if it slowly increases, as you may have a loss of fuel prime through a leaky injector seal, which would leak fuel into the crank case.

UhOh · Oct 10, 2017

Brian, he removed the Thermo Tee already (bypassed it). (ugh, I always shudder at the thought of fuel leaking into engine oil!)

atrussell129 · Oct 10, 2017

I will check the oil when I get home but when I changed it last month it wasn't any higher, and it didn't look like the oil was thinned out or anything like that when it was draining.

BobnOH · Oct 10, 2017

Perhaps the timing is set a bit too far advanced.

dataflow · Oct 10, 2017

Check / replace the non return valve on top of the fuel filter.

phaser · Oct 10, 2017

The OP replaced everything else, but no mention of the camshaft position sensor.

.

UhOh · Oct 10, 2017

phaser said:
The OP replaced everything else, but no mention of the camshaft position sensor..

Could a bad/marginal sensor only affect starts and not general engine performance? (I'm worried that if I learn too much about these engines that I'll end up with one!)

atrussell129 · Oct 10, 2017

I have not changed the camshaft position sensor yet because I did not think these engines will even start if those are bad, but I could be wrong. But there is not fuel return valve on this fuel filter because I replaced it with an older Fuel filter that did not have the thermostatic T in it.

phaser · Oct 10, 2017

UhOh said:
Could a bad/marginal sensor only affect starts and not general engine performance? (I'm worried that if I learn too much about these engines that I'll end up with one!)

My experience was the engine would frequently just quit running at the most inconvenient times, and restarts were longer than normal. Replacing the sensor fixed the problem.

Interesting thing was, VCDS showed no codes.

.

atrussell129 · Oct 10, 2017

also what is a Marginal sensor?

atrussell129 · Oct 10, 2017

I have never had an issue with the car randomly shutting off, once it starts it runs just fine, other than I feel as if it should be getting better than 37 mpg when must of my driving is 80 mph on the highway.

UhOh · Oct 10, 2017

"Marginal" means that it's enough to mostly work but not well enough to work as it should (w/o causing some minimum degradation). I defer to folks like phaser who actually have experience with these sensors.

If you're driving over 80mph on the highway I'm not thinking that's a way that one concerned about FE out to do. I believe that these cars are, on the average, likely to get about 45mpg at normal highway speeds (not even sure if it holds at 70mph). At 80 mph I'm thinking that 37mpg isn't necessarily that far off. Other thing to consider is the transmission: general rule of thumb is to figure about a 10% FE penalty for automatics vs manuals. Again, even here I do not have direct experience as I do not own a VW with a PD- I only am participating in this thread because last night I slept at a Holiday Inn

Rembrant · Oct 10, 2017

oilhammer said:
However it sounds to me like you have a loss of fuel prime. I would try cycling the key a few times, when you know it will act up...

^^This is the first test I'd be doing...see if it is losing prime.

dataflow · Oct 10, 2017

Rembrant said:
^^This is the first test I'd be doing...see if it is losing prime.

I agree. if you have any pinholes in fuel lines it can draw air in and run fuel away from the engine. I have not had this on any of our golfs but had it on several other diesels. you can pop in a non return valve after the filter and see if that helps. It is easy enough to do, and very low cost.

mjydrafter · Oct 10, 2017

IIRC the cam position sensor is really only used for quicker starts and reading the torsion value in VCDS. I'm pretty sure the car should start and run without it. It should give you a code if it's bad. Learn from my mistake and only replace it with a real deal VW sensor.

However, even when mine was bad, the car still started pretty quickly. So, I suspect that you have something else going on.

Just from my informal reading and my own car, 45 mpg is probably attainable in a BEW, but it's going to require some hyper-miling. Best I've done with mine is ~43.

oilhammer · Oct 11, 2017

Yes, the G40 CMP sensor is used in the PD for the cylinder TDC identification for the "quick start" function. At least that is what the PD engine self study guide says. There is probably more function there, but the self study guide does not mention it. However, the self study guide also makes no mention of the lambda sensor either, so.....

atrussell129 · Oct 11, 2017

what would be the best way to see if I am loosing my fuel prime? also where would I find a non-return valve for fuel?

atrussell129 · Oct 11, 2017

the only code I get is P0727, but this only happens when the car is cranking for a while if it starts right up a few times the code goes away, this is a brand new sensor from the dealer. I also have a manual transmission if that matters at all.

whitedog · Oct 11, 2017

I doubt it's the cam sensor but it may have sneaky issues later on. The reason I say this is because of how long the starts seem to be. Mine has long starts of maybe three seconds cranking and I have a cam sensor code pending and a cam sensor on the front seat. OPs issue seems to be very long cranking time. This points back to fuel. As mentioned, you can check this by cycling the key a couple times before starting.

atrussell129 · Oct 11, 2017

I do cycle the key a few times but this does not change anything, when I had the timing belt changed they said I should change my cam soon because it sounds like it is starting to go, but I looked up what those with a cam lob wearing down sounds like and mine sound the same as a regular tdi with no issues when running. I am very mechanically inclined as well.

steve6 · Oct 11, 2017

I was wondering why no one has mentioned the actual cam shaft, if you take off the valve cover you can see if the lobes are starting to get sharp...

oilhammer · Oct 11, 2017

steve6 said:
I was wondering why no one has mentioned the actual cam shaft, if you take off the valve cover you can see if the lobes are starting to get sharp...

Because that has nothing to do with his problem. That will not cause a long crank time. PDs with wiped out cam/lifters will still start right up. They just run poorly and make funky sounds.

oilhammer · Oct 11, 2017

steve6 said:
I was wondering why no one has mentioned the actual cam shaft, if you take off the valve cover you can see if the lobes are starting to get sharp...

Because that has nothing to do with his problem. That will not cause a long crank time. PDs with wiped out cam/lifters will still start right up. They just run poorly and make funky sounds.

If there is not any sign of fuel prime loss, I would want to check the torsion value. Maybe the G40 is flakey, too.

Replaced Everything Still Long Starts!! Help Please!!!

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