Cold start and sputtering.

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
Even though it is pretty warm out when I first start the car it has a sputting going on for up to 30 seconds and it shows it on the Tach. 2000 VW Tdi ALH with everything original except the injectors which are about 6 years old. All Highway driving with 420k miles on it. Never changed the MAF out nor starter or alternator. Any ideas?
 

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
Even though it is pretty warm out when I first start the car it has a sputting going on for up to 30 seconds and it shows it on the Tach. 2000 VW Tdi ALH with everything original except the injectors which are about 6 years old. All Highway driving with 420k miles on it. Never changed the MAF out nor starter or alternator. Any ideas?
OK I just unhooked the MAF Sensor and the car runs as good as it did if not better. After a drive I revved the engine up to 4800RPM's with no problem with it unplugged. I plugged it back in and it won't rev nearly as high.
 

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
OK I just unhooked the MAF Sensor and the car runs as good as it did if not better. After a drive I revved the engine up to 4800RPM's with no problem with it unplugged. I plugged it back in and it won't rev nearly as high.
Looks like I answered my own question. Changing out the MAF today.
 

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
OK got the Part today. Bosch MAF and put it in. That MAF must have been out a long time and I never knew until I got a lot of sputtering lately. Now I remember how good my car really runs. It's like having 25 extra HP.
UPDATE, Car runs great but it still has the first time startup problem of sputtering. I am now thinking it is the coolant temperature sensor. I will have it changed for me since I have a bad back and where that is located will not be good for me.
 

JohnTF

Veteran Member
Joined
Feb 23, 2009
Location
St. Paul , MN.
TDI
2003 Jetta 1.9 AT Wagon
Check the timing also , I've a posted a few threads about hard start / long crank [ 3-6 more if cold outside ] and then rough idle for 8-10 seconds .
Then ran fine after 1st start of the day .
I checked the timing and it was about 38* retarded , then latter adjusted now at 52* advanced , starts right away , still a little rough for a few seconds - separate issue - I think .
 

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
Check the timing also , I've a posted a few threads about hard start / long crank [ 3-6 more if cold outside ] and then rough idle for 8-10 seconds .
Then ran fine after 1st start of the day .
I checked the timing and it was about 38* retarded , then latter adjusted now at 52* advanced , starts right away , still a little rough for a few seconds - separate issue - I think .
I do have Vagcom and can check it if I knew how to. I could also change it if I knew how. Any tips appreciated.
 

JohnTF

Veteran Member
Joined
Feb 23, 2009
Location
St. Paul , MN.
TDI
2003 Jetta 1.9 AT Wagon
Check Ross-Tech on Youtube , they make some of the test system for these cars .
Then there are lots of others , some better / or worse than others .
This is my 1st go around with these car & systems and just getting familiar with .
I was in the bis some yrs. ago and was working when they 1st started putting computers & emissions in cars / trucks , even did smog testing in no. CA , had OTC , Snap On & others test gear , so gives a little head start .
I have the Ross-Tech KII-USB and downloaded the manual from Ross-Techs site .
Get familiar the manual for your gear , watch a few videos maybe multiple times , and then connect you Vagcom its easy once you get some understanding & watch it done a few times .
Tools required 22mm wrench [ I used a ratchet ] and 13mm socket & ratchet .

Look for lots of different YouTube videos , most are almost useless , a few are good .

Here's Ross tech's video ,
 
Last edited:

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
Check Ross-Tech on Youtube , they make some of the test system for these cars .
Then there are lots of others , some better / or worse than others .
This is my 1st go around with these car & systems and just getting familiar with .
I was in the bis some yrs. ago and was working when they 1st started putting computers & emissions in cars / trucks , even did smog testing in no. CA , had OTC , Snap On & others test gear , so gives a little head start .
I have the Ross-Tech KII-USB and downloaded the manual from Ross-Techs site .
Get familiar the manual for your gear , watch a few videos maybe multiple times , and then connect you Vagcom its easy once you get some understanding & watch it done a few times .
Tools required 22mm wrench [ I used a ratchet ] and 13mm socket & ratchet .

Look for lots of different YouTube videos , most are almost useless , a few are good .

Here's Ross tech's video ,
Thanks I will give it a look tomorrow. I would guess VCDS and the Vagcom programs are pretty much alike.
 

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
Check Ross-Tech on Youtube , they make some of the test system for these cars .
Then there are lots of others , some better / or worse than others .
This is my 1st go around with these car & systems and just getting familiar with .
I was in the bis some yrs. ago and was working when they 1st started putting computers & emissions in cars / trucks , even did smog testing in no. CA , had OTC , Snap On & others test gear , so gives a little head start .
I have the Ross-Tech KII-USB and downloaded the manual from Ross-Techs site .
Get familiar the manual for your gear , watch a few videos maybe multiple times , and then connect you Vagcom its easy once you get some understanding & watch it done a few times .
Tools required 22mm wrench [ I used a ratchet ] and 13mm socket & ratchet .

Look for lots of different YouTube videos , most are almost useless , a few are good .

Here's Ross tech's video ,
WOW was that a nightmare. Timing was 40-45 on the graft, retarded. GOT it now though. First I thought there was only one 13mm bolt. Then I thought there were 2 but there is 3 of them and I didn't pick that up from the video.(OLD AGE). After I finally got the 3 bolts loose I adjusted it. Car would not start, thought I went too far advanced, Move it back a couple more times and it was still too far. After about 15 tries I got it slightly advanced. Ran fault codes and cleared the MAF code and one other thing. Then I ran all codes and as it has always been I have 2 codes and they are just the Interior Light and the Drivers side heated mirror. Had that Vagcom program for years and years . Never used it except to check codes before. Now I know a little more. By the way, one of those 13 mm bolts was almost ready to fall off. It must of been loose a long time. ALso the IP does have a slight leak. Not bad but it was wet on the inside part.
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
Nice work getting it sorted.
Another handy thing you can do with the VAGcom is checking the various temperature sensors. You check them all code, then hot. Bad sensor will show wack reading. Save you from changing that coolant temperature sensor unnecessarily.
A4 TDI engine measuring blocks/groups
 

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
Nice work getting it sorted.
Another handy thing you can do with the VAGcom is checking the various temperature sensors. You check them all code, then hot. Bad sensor will show wack reading. Save you from changing that coolant temperature sensor unnecessarily.
A4 TDI engine measuring blocks/groups
Thanks, If it is still sputtering in the morning I will check those temps.
 

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
Check Ross-Tech on Youtube , they make some of the test system for these cars .
Then there are lots of others , some better / or worse than others .
This is my 1st go around with these car & systems and just getting familiar with .
I was in the bis some yrs. ago and was working when they 1st started putting computers & emissions in cars / trucks , even did smog testing in no. CA , had OTC , Snap On & others test gear , so gives a little head start .
I have the Ross-Tech KII-USB and downloaded the manual from Ross-Techs site .
Get familiar the manual for your gear , watch a few videos maybe multiple times , and then connect you Vagcom its easy once you get some understanding & watch it done a few times .
Tools required 22mm wrench [ I used a ratchet ] and 13mm socket & ratchet .

Look for lots of different YouTube videos , most are almost useless , a few are good .

Here's Ross tech's video ,
Thank for the Video and help. I was retarded on the Ip timing.
 

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
Nice work getting it sorted.
Another handy thing you can do with the VAGcom is checking the various temperature sensors. You check them all code, then hot. Bad sensor will show wack reading. Save you from changing that coolant temperature sensor unnecessarily.
A4 TDI engine measuring blocks/groups
Checked the Coolant temp sensor. 37.8 Cold and 74.8 Hot. So I guess it is ok.
 

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
Checked the Coolant temp sensor. 37.8 Cold and 74.8 Hot. So I guess it is ok.
So is there any other ideas on why I get sputtering when I first start the car? It last around 30 seconds. Tach jumps and if I don't let it settle down and drive off the car sputters.
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
Interweb guessing- Perhaps there is just a small bit of air getting in the fuel system. Have you ever changed the little viton fuel return tubes from the injectors?
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
Once running, fuel system purges fairly quickly. I'm just guessing what might cause mis-fueling for just the first half minute. I do know at idle, most of the fuel delivered to IP is sent right back out the big return line. If your vacuum and fuel return lines are factory, I would replace them all. A small bit of grease on the thermostatic tee o-rings also might help.
 

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
Once running, fuel system purges fairly quickly. I'm just guessing what might cause mis-fueling for just the first half minute. I do know at idle, most of the fuel delivered to IP is sent right back out the big return line. If your vacuum and fuel return lines are factory, I would replace them all. A small bit of grease on the thermostatic tee o-rings also might help.
OK thanks I will think about getting the fuel line replaced? Is it the Return line from the pump to the filter or the Pump to the Injector?
 

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
Once running, fuel system purges fairly quickly. I'm just guessing what might cause mis-fueling for just the first half minute. I do know at idle, most of the fuel delivered to IP is sent right back out the big return line. If your vacuum and fuel return lines are factory, I would replace them all. A small bit of grease on the thermostatic tee o-rings also might help.
Is the return line from the injector to the fuel pump 3MM? I just tried to take it off because it looked frayed. Got it off and now I need a new one. I had a fuel line in a bag from a long time ago and it say's 1 meter and is too large. ID 1617 on the bag. Not even sure where I got it. I also should mention I had all the vacuum lines replaced. Just not the fuel.
 

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
Once running, fuel system purges fairly quickly. I'm just guessing what might cause mis-fueling for just the first half minute. I do know at idle, most of the fuel delivered to IP is sent right back out the big return line. If your vacuum and fuel return lines are factory, I would replace them all. A small bit of grease on the thermostatic tee o-rings also might help.
Changed out all the return lines and will see what happens when I start it next time when cold. All those lines were brittle and just broke off. Had to use some needle nose pliers to get it all off the nipples.
 

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
Yes, 3mm fuel rated hose (viton).
OK wasn't the return lines. I just got to thinking (sometimes dangerous) A long time ago I bought one of those Tuning boxes you attach to the MAF sensor. I used it for about 2 weeks and decided I didn't want a ticket since it was so much more fun to drive. I took it off. So bottom line is, if I disconnect the MAF sensor I don't get the sputtering. I will see if I can remember which wire I attached that to and see what it looks like. Possibly a weak wire. So far I timed the IP which was needed, bought a new MAF, needed also and changed out the return lines which was needed.

By the way that tuning box was about 10 years ago.
 

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
OK wasn't the return lines. I just got to thinking (sometimes dangerous) A long time ago I bought one of those Tuning boxes you attach to the MAF sensor. I used it for about 2 weeks and decided I didn't want a ticket since it was so much more fun to drive. I took it off. So bottom line is, if I disconnect the MAF sensor I don't get the sputtering. I will see if I can remember which wire I attached that to and see what it looks like. Possibly a weak wire. So far I timed the IP which was needed, bought a new MAF, needed also and changed out the return lines which was needed.

By the way that tuning box was about 10 years ago.
OK went out and looked over the wires to the MAF. No visible damaged to them. Could the connections on the plug be bad? I have used MAF cleaner on them before.
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
..................snip........................if I disconnect the MAF sensor I don't get the sputtering...................snip........................
Now that's a clue. You've ruled out the MAF itself, so it must be something that interacts with the MAF or faulty wire/connects..
More info here-https://www.myturbodiesel.com/d2/1000q/multi/maf-faq-tdi.htm
 

Lefty

Veteran Member
Joined
Oct 21, 2005
Location
Lazear,Colorado Population 60
TDI
Jetta, 2000,Green GLS
Now that's a clue. You've ruled out the MAF itself, so it must be something that interacts with the MAF or faulty wire/connects..
More info here-https://www.myturbodiesel.com/d2/1000q/multi/maf-faq-tdi.htm
Just for grins I will replace the connector. I read they can break when taken off the MAF sometimes. Could possibly be just a loose connection. WHO KNOWS.
 

BobnOH

not-a-mechanic
Joined
May 29, 2004
Location
central Ohio
TDI
New Beetle 2003 manual
I know my connector on my previous TDI (99.5) had a broken connector, never an issue as all the connects were fine.
 
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