99 ALH hot start issue

sold a 99.5 MK4 jetta to a friend, 240k on it, 5spd one owner car that was amazingly clean.


cold it starts right up, once its hot and want to start again it will crank for about 4 seconds before starting.

i am guessing it's fuel related however no lift pump here so not sure what to do

Click on the Hamman Mod in my signature. I had a 99.5 with the exact same thing. and it made mine way easier to start.

Known factory issue. Malone tuning has a fix for it, $99.

https://malonetuning.com/ecu-tuning/audi-volkswagen/tdi/ve-tdi

ToxicDoc said:

Known factory issue. Malone tuning has a fix for it, $99.

https://malonetuning.com/ecu-tuning/audi-volkswagen/tdi/ve-tdi

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That is the only good solution. Also consider, if it's in good nick, going as high as Stage 2 tune. The clutch in those early TDIs is a bit more stout and can handle it. You do have to pay an extra fee to have the ECU socketed.

Get the tune.

Miss my 99.5, but this issue makes the car a pain when warm.

The fueling tables have an error where they ECU will not fuel under 250 cranking rpm with the engine warm. If you have a new battery and a new starter, it will usually crank fast enough that the issue does not occur.

As the cranking system ages, this extended crank will occur.

As above, a tune is the best option. Other than that, you can bypass the error by fooling the ECu into thinking the car is cold - either by modding the Temp sensor reading or unplugging the temp sensor and then plugging back in once the car is started.

BobnOH said:

That is the only good solution. Also consider, if it's in good nick, going as high as Stage 2 tune. The clutch in those early TDIs is a bit more stout and can handle it. You do have to pay an extra fee to have the ECU socketed.

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the car is bone stock, one owner car with somehow no rust on the fenders or anywhere that is typical, only the rear driver door is rusting because there was damage so they replaced the door skin years ago.

so would he be able to do an exhaust and mild tune on the car without smoking the clutch? i believe this one is newer and replaced but not 100% sure, i'll have to have him look in the 1" stack of receipts.

I just know the factory clutch on the '99 was stronger than the later models. Handled a stage 2 all stock, felt like 30% more power. But if you have a replacement clutch, who knows.
I will say this about the hot starts, my recently totaled '99 had the issue for years and it never failed to start. It was really just annoying.

You want to be sure the cars running right before you tune.

I used the Hamman mod on mine a year or so ago and no problem since, as long as I remember to press the button. Works great.

Easily fixed with software, known issue... surprised there are any 1998-1999 ALHs left that are still stuck that way, LOL.

oilhammer said:

Easily fixed with software, known issue... surprised there are any 1998-1999 ALHs left that are still stuck that way, LOL.

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just did a tune on two 99.5 cars in the last few months, both customer cars, both had the hammon mod i installed years ago, was nice to get rid of extra underhood wonk and a little power to boot... yeah, not many of those left on the road

My 99 has this issue still. It fires up fast enough for me that it's not worth the cost of a tune.

My 02 just starting to have this problem @230k. Supposedly my car has a stage 1 tune too

burn_your_money said:

My 99 has this issue still. It fires up fast enough for me that it's not worth the cost of a tune.

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$99 too much?

burn_your_money said:

My 99 has this issue still. It fires up fast enough for me that it's not worth the cost of a tune.

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hashahah

ToxicDoc said:

$99 too much?

Click to expand...

To fix a 3 second inconvenience? You betcha.

burn_your_money said:

To fix a 3 second inconvenience? You betcha.

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x how many starts?

x how many extra starters due to the excess cranking...

Penny wise, pound foolish something something...