Hard Starting - Troubleshooting not helping

Fever

Member
Joined
May 19, 2010
Location
Bellingham, WA
TDI
1999 Jetta
Hi all-

Have a 1999-1/2 VW Jetta TDI with 280K miles, manual trans.

This issue started probably 60K miles ago, but is now so bad, it's embarrassing.

When cold starting, the engine cranks and cranks, tries to fire and then eventually fires after probably 10 seconds. Huge cloud of smoke. Smoke smells like diesel, not motor oil. Slightly rough idle for a few seconds, then all is well. If I try re-starting while engine is warm, no problems at all.

Glow plugs replaced a while ago for this, but didn't make any difference. Glow plug light comes on and goes off quickly down to approx 40F weather.

It is interesting that down around 30F or colder, the glow plugs stay on to warm the cylinder, and the engine fires when cranked and no smoke. In my opinion, in cold weather, engine cold start behaves as expected.

Was wondering if at this age, the injectors are dirty and spewing too much? fuel when starting. Really not a diesel guy, but love this jetta and want to keep driving up and down the freeway as long as I can. Still getting 47-48 mpg and power seems sufficient. Haze of smoke when accelerating down the on ramp, otherwise, none.

Where is a good place to start? I've done the hard starting tips on this forum and it didn't help.

Thanks,

Mike
 

KLXD

Top Post Dawg
Joined
Aug 22, 2009
Location
Lompoc, CA
TDI
'98, '2 Jettas
When was the timing belt done last? Have you checked the timing? Maybe it's slipped and is retarded?
 

jprine

Veteran Member
Joined
Feb 9, 2009
Location
Chicago
TDI
03 GLS Golf TDI, 04 R32, 05 Passat Wagon TDI
"When cold starting, the engine cranks and cranks, tries to fire and then eventually fires after probably 10 seconds. Huge cloud of smoke."

"...down around 30F or colder, the glow plugs stay on to warm the cylinder, and the engine fires when cranked and no smoke."

How cold is it when it is hard to start and runs rough/smokey a bit? Seems normal to me when its really cold my car has always been like that (<15F or so). Starts great 30F+ if thats what you were trying to say. Part of the reason I would plug the heater in, and why I now have a espar.

I've had my car 135k / 2 timing belt changes and its never gotten any better or worse. My brother has same car and his does it also.

The white powerservice additive helps.

edit:
I reread your post, sounds like your only having trouble above 30F when its not that cold? ok that is strange..
 
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Fever

Member
Joined
May 19, 2010
Location
Bellingham, WA
TDI
1999 Jetta
Cold starting...any time I haven't ran the engine for about eight hours. It could be sixty outside and still smoke and excessive cranking. When the air gets down to thirty, the glow plugs activate and engine starts fine. A few cranks, fires right away. Minimal smoke.


Timing belt changed every 60k miles. It's about 40k on it now. Same problem didn't change whenbelt was changed last time. This issue has been around quite a while but is continually getting worse.

Thanks.
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
I'm not sure, but the 99.5 models may have a programming issue that is solved with a re-flash (whatever it's called) of the ECU ...... then, properly timed, etc., no more hard starts.

There is a discussion somewhere about extending glow plug "glow" time. Which, other than extreme cold, is not much help above 30ish F.

Unless I've missed it, there is no way to program the ECU to glow the plugs at a higher ambient air temp.

There are 100k mile change interval TB kits with all the items necessary to do the job! There's no logical reason to be changing your TB every 60k miles!

I'd start by checking the timing as others have indicated.

Also, is the Check Engine Light on?
 

Fever

Member
Joined
May 19, 2010
Location
Bellingham, WA
TDI
1999 Jetta
Timing belt interval is from the VW owners manual and Bentley manual. They don't match, but are around 60K miles, IIRC.

Check engine light is NOT on.

Thanks,

Mike
 

jprine

Veteran Member
Joined
Feb 9, 2009
Location
Chicago
TDI
03 GLS Golf TDI, 04 R32, 05 Passat Wagon TDI
Hard to start when hot issue.....
Somewhat different, but also 99.5 starting problems. Could be useful.

They say if you disconnect the coolant sensor it runs the glow plugs as if it were cold outside and also advances the fuel pump timing and quantity. It seemed to make it the problem go away for them, maybe try it and see?

"Timing belt interval is from the VW owners manual and Bentley manual. They don't match, but are around 60K miles, IIRC."
Depends on the parts you use, they changed a couple parts on newer model years of that engine and changed it to 100k. If you put the updated kit on you can do 100k
 

AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
We know what your manual says about TB change interval as well as the Bentley.

But, there is a "kit" with a 100,000 mile TB and all the parts (water pump, rollers, tensioner, bolts, etc.) that replaces the 60k mile interval ........

All of the vendors that support and participate with this web site offer the kit at very competitive prices.....

It's good to know the CEL is not on.

And, the link jprine provided has good info to help you!

EDIT: What jiprine said about disconnecting the temp sensor is correct. But, it will also throw the CEL... just so you know!
 
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Fever

Member
Joined
May 19, 2010
Location
Bellingham, WA
TDI
1999 Jetta
But, there is a "kit" with a 100,000 mile TB and all the parts (water pump, rollers, tensioner, bolts, etc.) that replaces the 60k mile interval ........

It's good to know the CEL is not on.

And, the link jprine provided has good info to help you!

EDIT: What jiprine said about disconnecting the temp sensor is correct. But, it will also throw the CEL... just so you know!
Well shoot.. I paid to have the belt changed, so I guess i need to call and see what they do as far as parts. They DO change the idler, water pump and belt.

Thanks everyone for the pointers.

Mike
 

Fever

Member
Joined
May 19, 2010
Location
Bellingham, WA
TDI
1999 Jetta
Alrighty... Took to the reputable shop I've been referred to and using for years.

They checked injection timing and water temp sensor, glow plugs. No air in fuel sight glass(tube).

The above checks out. They are reluctant to pull the injectors. He mentioned "that's getting invasive" Well crud. Guess I'll be doing the invasive inspection and pull them.

My gut keeps telling me the engine is flooded and until it spins long enough to burn some of that fuel off, it doesn't fire and run. Acts just like clearing a flooded gas engine. For quite a while, (a year?) this has been getting worse until now it's not bearable. My initial feeling was maybe an injector was dripping all day/night and causing excessive fuel at startup.

Will let you know what I find. Will take a couple weekends to get an injector pressure tester and get to it.

Thanks,

Mike
 

maxmoo

Veteran Member
Joined
Jan 19, 2011
Location
Lakefield, Ontario, Canada
TDI
2000 golf, 2001 golf, 2000 beetle, 2003 wagon, 2004 golf, 2004 jetta, all diesels
Don't use your guts to diagnose tdi issues.....unles maybe you have years of experience behind you.

This is a diesel not a gas engine...no spark plugs to flood.....
I think you are likely barking up the wrong tree.....I wouldn't touch the injectors yet.
You say it starts good when the temp is below 30f.......your injectors seem to work ok then....right?

Did you try disconecting the wiring harness at the coolant temp sensor (cts)?

Are you sure the guy that checked your timing knows what he's doing?
I would find another tdi guru for a second opinion.
 
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AndyBees

Top Post Dawg
Joined
May 27, 2003
Location
Southeast Kentucky
TDI
Silver 2003 Jetta TDI, Silver 2000 Jetta TDI (sold), '84 Vanagon with '02 ALH engine
Alrighty... Took to the reputable shop I've been referred to and using for years.

They checked injection timing and water temp sensor, glow plugs. No air in fuel sight glass(tube).

Unless the mechanic used appropriate testing software, such as Vag Com Diagnostic System (commonly referred to as VCDS), he never checked timing. Checking the CTS would require unplugging it and testing the ohms resistance ... pretty hard to get to that thingy without removing it which cause loss of coolant, unless coolant is drained. Unless there was a CEL (Check Engine Light) DTC (Diagnostic Test Code), the CTS would be known to be fine without "testing" it. ...... Testing GPs... same thing, the CEL will come on if one or more of them are out of range. At what temp did he check to see if the GPs were receiving current. Or, did he check for current? I'm not sure what "glass tube" you are observing fuel through.


The above checks out. They are reluctant to pull the injectors. He mentioned "that's getting invasive" Well crud. Guess I'll be doing the invasive inspection and pull them.

Would your mechanic know what to do with the Injectors once he pulled them? Does he have testing equipment? There is virtually zero visual things that tell you an Injector is bad.

My gut keeps telling me the engine is flooded and until it spins long enough to burn some of that fuel off, it doesn't fire and run. Acts just like clearing a flooded gas engine. For quite a while, (a year?) this has been getting worse until now it's not bearable. My initial feeling was maybe an injector was dripping all day/night and causing excessive fuel at startup.

A diesel engine basically only needs three things to run, Air, Compression (about 400 psi) and Fuel. Really, there's no such thing as flooding. The injectors do not pop (open) until the right amount of pressure (about 2900 psi) is applied at the right TIME by the Injection Pump. When the engine is not running, there is no fuel pressure on the injectors (maybe one, key word > maybe). And, if there was "excessive" fuel at start-up, there would be excessive smoke too... maybe lots of it.

Will let you know what I find. Will take a couple weekends to get an injector pressure tester and get to it.

Thanks,

Mike
As I initially posted, 99.5 engines and earlier (many of them) have a hard start issue that's caused by programming in the ECU. My cousin has a New Beetle that drove him nuts with starting issues. I did all the tests with my VCDS and more...... to no avail. I removed the ECU and sent it off for a re-flash or whatever it is they do to them.......... No more hard starts.. He's happy!:D

Seems like the cost was about $100.00 plus shipping for the re-flash. They actually send you another ECU that's already been re-flashed.
 

UhOh

Top Post Dawg
Joined
Dec 24, 2014
Location
PNW
TDI
2000 & 2003 Golf GLS (2005 Mercedes E320 CDI)
As reported, this sounds like something is degrading. I'd look into the issue that Andy notes, but I think that this issue would have caused this problem all along.

The low-hanging-fruit approach would be to, as maxmoo suggests, unplug your CTS.

I've come to note that TDIs tend to be a bit more fidgety when temps are not quite low enough to trigger the GPs and not quite warm enough to provide for better starting. If there's something else going on then this behavior is exacerbated.

What's your cranking RPMs when you're struggling? You really want over 200 RPM: 250 is where I like to see it. Battery, starter and or wiring (grounds) come in to play here.

I know that IQ can affect things, though it shouldn't hamper with the initial starting: I know that it can have an affect once the engine fires up. IQ doesn't tend to "degrade," but it's something to have checked anyway (but only after the above things).

I'd look to have a compression test done if you're still having difficulties after looking into all the above.
 

jetta 97

Vendor
Joined
Dec 25, 2008
Location
Dallas (McKinney) ,TX ,USA
TDI
2 X Jatta MK5 2006
As I initially posted, 99.5 engines and earlier (many of them) have a hard start issue that's caused by programming in the ECU. My cousin has a New Beetle that drove him nuts with starting issues. I did all the tests with my VCDS and more...... to no avail. I removed the ECU and sent it off for a re-flash or whatever it is they do to them.......... No more hard starts.. He's happy!:D

Seems like the cost was about $100.00 plus shipping for the re-flash. They actually send you another ECU that's already been re-flashed.
ANDY
this is when engine is Hot , Hot start problem.
He said he has problem with Cold start.
Reflash will not fix CLOD start.
This is most likely either mechanical timing, Pump timing problem.

Also reflash is not $100, it is much more ,this ECu has to be socked where chip goes first they you reflash it, Usually goes with Tuning file.

If mechanical timing and pump timing is good , This could help as well :
http://forums.tdiclub.com/showthread.php?t=123304
 
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KLXD

Top Post Dawg
Joined
Aug 22, 2009
Location
Lompoc, CA
TDI
'98, '2 Jettas
The shop checked the timing. Can you verify they used VCDS or other software for this?
 

sisyphus

Veteran Member
Joined
Dec 8, 2008
Location
Appleton, Maine
TDI
99.5, '01 A4 Jetta sedans, 5 sp box, Hamman mod, Joey mod, Bilsteins, 2.00" lift
Did you check the thermostatic tee at the top of the fuel filter? The IP could be losing some prime through that, getting the initial squirt through to the injectors with what's already in it but then losing it immediately afterward for a few seconds before gaining it back.
Just a thought.
 

Fever

Member
Joined
May 19, 2010
Location
Bellingham, WA
TDI
1999 Jetta
Sorry it took so long to update, but about a month ago, I ran Diesel Purge through the fuel system down stream of the fuel filter.

Starts reasonably quick (1 second of cranking....) and only a modest puff of smoke... Like it's been since I bought it 120,000 miles ago until recently.

Thanks,

Mike
 
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