starter cranking longer, why???

lee · #1 11-09-2003, 07:07 PM

Over the last couple of weeks it seems to me that it takes longer for my engine to come to life. There's no issue with low starter motor rpms that I can tell, battery & alternator are OK. Gas mileage has stayed constant, I have no noticable mis-firing. Most noticable on a cold/cool start. Not every time BTW, just to make it interesting. The only thing I find different is the length of time from the starter beginning to spin to engine lighting up. No CE lights.

Plugs changed about 10K miles ago as well as TB cleaned, new air filter, MAF sensor wire cleaned, all at the same time as the plugs were done. Last time engine was touched (other than pulling & replacing dip-stick) was an oil change about 6weeks or 2K miles ago. FYI, I have not changed the fuel filter, but probably will on Tuesday.

injectors?

Ron Mummert · #2 11-10-2003, 07:57 PM

Not that I can help or anything, but I think SOMEONE should respond to your post. Actually, I think, 1. It's electrical related. 2. It's fuel related. 3. It's sensor related. 4. It's all of the above, or any combination of two.
Since I've straightened everything out for you, Lee, help me with this one.
My car has run flawlessly for close to 3 years & 50K.....EXCEPT for one rarely occuring "happening". If I start the engine cold, back it out of the garage to wash it, so it's been running for 10 secs. Restart it to pull back into the garage (this is no problem), but then the next morning......Jeez! Upon starting, it catches & runs & for 2 seconds sounding like the crank has six empty beer cans attached it it. This racket stops, but now it's firing on 2, maybe 3 cylinders. After 10 seconds, the other 3 cylinders get the message, and after a minute of this sputter routine, it smooths out & acts like the precision Japanese touring machine I blew seven grand on.
Now, my thinking says I've "tricked" a sensor into a psychotic state, & the sensor says, "You idiot, you're supposed to drive me a few miles after you start me". "Therefore I rattle my cams at you as a warning to do so in the future."
Uh.....or not.
Any guesses?
Thanks, Lee.
(Come on, NASA MUST be able to figure this out)!

Ron (Crankin' my cans).

marlettpat · #3 11-10-2003, 07:58 PM

yeah me too.......it sucks, no svx on the road at the moment

lee · #4 11-10-2003, 08:48 PM

Quote:

Originally posted by Ron Mummert
Not that I can help or anything, but I think SOMEONE should respond to your post. Actually, I think, 1. It's electrical related. 2. It's fuel related. 3. It's sensor related. 4. It's all of the above, or any combination of two.
...snip......Jeez! Upon starting, it catches & runs & for 2 seconds sounding like the crank has six empty beer cans attached it it. ...snip...
Any guesses?

Ron (Crankin' my cans).

Thanks Ron, I believe you have hit the nail on the head with this diagnosis.

Now maybe I can return the favor. Are you by any chance kicking back with a cold one (or two, or three, or...) admiring your work, opening the hood and throwing your empties up by the fan belts? Oh wait a minute, SVXphile (Don) told me your preferred poison is "Box 'O Wine" not beer...never mind, I'll do so more thinking.

Ron Mummert · #5 11-10-2003, 09:18 PM

Quote:

Originally posted by lee

Oh wait a minute, SVXphile (Don) told me your preferred poison is "Box 'O Wine" not beer...never mind, I'll do so more thinking.

Don's correct. I changed poisons to celebrate the boxer engine.
Cardboard should be rather quiet when scrambled by the belts, although my mind is rather scrambled when belting the box.

Ron.

svxfiles · #6 11-11-2003, 03:59 PM

The fuel pump holds line pressure when the engine is off. When the check valve goes bad it takes longer to push fuel to the injectors. I found this out after i installed my adjustable fpr. When i shut off the engine the pressure drops to zero. it should not do that, so untill i install a new fuel pump, i just have to live with it

lee · #7 11-11-2003, 04:29 PM

svxfiles,

This makes some sense. How do you know it's the check valve? Did you put a pressure gauge inline?

Ron,

Have you ever tried the same routine, but without the wash, to see if the car acts the same, i.e., does water have something to do with it, or is it just the time?

oab_au · #8 11-11-2003, 05:11 PM

Quote:

Originally posted by lee
Over the last couple of weeks it seems to me that it takes longer for my engine to come to life. There's no issue with low starter motor RPMs that I can tell, battery & alternator are OK. Gas mileage has stayed constant, I have no noticeable misfiring. Most noticable on a cold/cool start. Not every time BTW, just to make it interesting. The only thing I find different is the length of time from the starter beginning to spin to engine lighting up. No CE lights.

Plugs changed about 10K miles ago as well as TB cleaned, new air filter, MAF sensor wire cleaned, all at the same time as the plugs were done. Last time engine was touched (other than pulling & replacing dip-stick) was an oil change about 6weeks or 2K miles ago. FYI, I have not changed the fuel filter, but probably will on Tuesday.

injectors?

Gid'ay Lee, I suppose it depends on if the engine runs ok when it does start.? If it stumbles and farts for a while, or runs clean.
You say it does not do it all the time.

If it was the fuel reg not holding pressure, you could check it by opening a fuel line before you start to check for pressure.

If it was the cold start valve it would stumble when it does start till it was warm enough, have to keep it running with the throttle.

Temp sensor would do it all the time when cold, though Florida wouldn't get any colder than Coffs Harbour which can hide the fault.

When starting the ECU is looking for a pulse from the crankshaft sensor to signal that the engine is turning. It takes about 6 pulses to start. If this sensor is having problems, which they do as it is a magnetic pick-up, there will be no action till it does get the signal. This can be checked at the time by watching the rev counter, if it does not show that the engine is turning over, then jumps into action as it starts, there is no pulses coming from the crankshaft sensor. The output from the sensor when cranking should be about 0.1volt AC. Same goes for the cam sensor.

Then again it could be the ignition switch having mechanical problems

Back to you mate.

Harvey.

svxistentialist · #9 11-11-2003, 05:23 PM

Quote:

Originally posted by Ron Mummert

Don's correct. I changed poisons to celebrate the boxer engine.
Cardboard should be rather quiet when scrambled by the belts, although my mind is rather scrambled when belting the box.

Ron.

Mine too, Ron.

Although the phrase may well mean something completely different over here.

svxistentialist · #10 11-11-2003, 05:33 PM

Regards Lee's original question: The possible drop in fuel pressure may be the cause of the symptom happening some times, and not others.

I am in the habit of turning on my ignition, and not turning the starter till the pump stops building up pressure. You hear it stopping if you listen for it, but there is a more noticable relay click from behind the clocks. This actually takes quite a few seconds, so maybe my "check valve" that svxfiles mentions is faulty, I dunno.

Lee, I was wondering if yours may be the same? Maybe sometimes you switch on the ignition, spend a few seconds looking for glasses [sunglasses in Fla!!], seatbelt whatever. Then it starts instantly, as the pressure is up. Other times you get in, try the starter immediately on switch-on, and it won't fire up till fuel pressure comes up. Plausible?

Joe

lee · #11 11-11-2003, 05:41 PM

Harvey,

It almost always runs normal on a start. Perhaps every tenth time it has a bit of a stumble on a cold start, but once it begins to move the hesitation disappears and does not return. The rev counter has never shown any fault signs.

If time allows this weekend, I will check fuel pressure. Am I right in assuming that if the fuel pump is holding pressure I should get quite a strong stream from the fuel line even without the engine having been run in hours? I'm presuming I would pinch a line, then remove an end and put the opening into a jar, then "unpinch"?

Ron Mummert · #12 11-11-2003, 06:59 PM

Quote:

Originally posted by lee
svxfiles,

Ron,

Have you ever tried the same routine, but without the wash, to see if the car acts the same, i.e., does water have something to do with it, or is it just the time?

The first couple of times I turned the car into a diesel, I really didn't associate the short running time with the morning restart, so I can't say for sure whether it was for a wash job, or my simply retreiving a loose bottle (which is why the box makes sense). I would doubt the water was involved as I don't spray the engine bay, & as I mentioned, the car starts normally right after the bath, & I pull it back into the bat cave. I guess I could try to duplicate the process, but that noise....I'd rather listen to nine inch nails on a chalkboard.

Opps...time to go watch "24".

Ron.

oab_au · #13 11-11-2003, 07:02 PM

Quote:

Originally posted by lee
Harvey,

It almost always runs normal on a start. Perhaps every tenth time it has a bit of a stumble on a cold start, but once it begins to move the hesitation disappears and does not return. There's a stumble that lasts until the engine is warm. The rev counter has never shown any fault signs.

If time allows this weekend, I will check fuel pressure. Am I right in assuming that if the fuel pump is holding pressure I should get quite a strong stream from the fuel line even without the engine having been run in hours? I'm presuming I would pinch a line, then remove an end and put the opening into a jar, then "unpinch"?

OK then it is not the crank pick up.

Yes it should hold pressure overnight, wont be much of a flow just a spurt. The pump does run when you turn on the ign, but it does not know if there is pressure there or not. It just runs for a few seconds then switches off till it gets the crank sensor pulse.

The cold start valve under the RHD side of the manifold can stick from gum to not open fully. Won't post a code.

Harvey.

gl1674 · #14 11-11-2003, 07:03 PM

Quote:

Now, my thinking says I've "tricked" a sensor into a psychotic state, & the sensor says, "You idiot, you're supposed to drive me a few miles after you start me

Ron,

Judging by your description you have engine flooding. This is a well-known issue with VW turbo engines - if it did not run long enough, it will have a problem starting the next time.

Basically ECU is enriching mixture when it is trying to start engine, it does so by gradually increasing amount of fuel. If it goes too far it soaks spark plugs and nothing good happens until the spark/cylinder dries up a bit.

Next time after you washed the car and put it into garage, try to crank it with throttle fully open. It will take engine longer to catch (3-5 seconds), but then it should run normally. And yeah, don't forget to release the throttle once it starts. This is the flood clearing procedure, it is programmed in ECU. If engine runs normall after that, the flooding theory is confirmed.

The other possibility is moisture playing up with electrical connections - it would not be cured by full throttle start.

svxfiles · #15 11-11-2003, 07:21 PM

Lee, yes i do have a pressure guage on my return line too the tank. i just went out now to see. before the ignition is turned on the pressure reads zero,when the ignition was turned on,the guage jumps up to 40 or so psi for 7-8 seconds, then it drops to zero. when it starts, it goes up to 48 psi.