Pls Help. Hard starting, prolonged cranking - ALH

I have a 99.5 Mk4 ALH. After the car has been driven, been running and its hot, if I shut it off and try to start it a few minutes later it cranks for sometimes up to 3 seconds or more before it starts up. Almost like its cold starting in the morning. Does anyone know what would cause this? In my past experience whenever a diesel is hot it usually fires up in a split second.

Theres a glitch in the ECU that causes that. 3 seconds is not bad, I was up to something like 15 seconds!

I have since installed a single mass flywheel and a new Bosch reman starter. No more hard hot starts. Fires up instantly hot or cold.

I believe 250RPM and below cranking speed is where the glitch lies.

I thought there was a reflash for the ECU to fix that for the '99.5??

As mentioned above, there is an ECU software glitch that causes this. If the ECU is reflashed with 2001 software, the problem will be eliminated. Most people will have the car tuned, and this will eliminate the problem as well as increasing your performance a bit. Plus, it will not effect your fuel economy.

-Rich

Thanks for the quick replies guys. I do have a single mass lightened flywheel in the car now. So if I get some software like Alligator or RC that should solve my problem? So I can relax knowing that its not something that is wrong with the car? Thanks again!

Yes, and yes. There's another similar thread from last week I believe where someone actually posted the fuel map that demonstrates the problem. Zero fuel is injected at warm temps until the rpm goes above 250. That means that even though the engine is nice and warmed up, if the starter can't spin it fast enough, it won't start. With the corrected fuel map, the dead spot is eliminated.

I'm curious how or if the problem was resolved.......I have a similar issue with my '98 NB TDI.

My '01 Jetta TDI cranks over and fires up right away. Both spin at approx. the same rpm while cranking.

Can this fuel map be changed using Ross-tech VagCom? I have been searching this without any luck.

Thanks in advance.

DougInFL said:

Can this fuel map be changed using Ross-tech VagCom? I have been searching this without any luck.

Thanks in advance.

Click to expand...

No, I beieve the ECU has to be either "reflashed" or if you upgrade to a tune as mentioned it will be resolved.

705 posts HERE about this issue.

Another option is to recode the system to lie to the ECU and make it think you have the automatic transmission instead of the 5 speed. RocketMan Jeff did this for me at Impex and it eliminates this problem, but you will get a CEL for non-communications with the TCU that isn't there.

Dave

For about five bucks you can do the Hamman mod on your car. Solves the problem without any further issues. I had the same problem, did the mod three years ago.

On edit:
Here's the link http://forums.tdiclub.com/showthread.php?t=116576&page=3