Hammond Mod ??

cod

Veteran Member
Joined
Nov 22, 2008
Location
St.John's,Newfoundland,Canada
TDI
2006 Jetta
Hi,
I have been reading the hard to start when hot thread and see the Hammond Mod talkd about.
Where is the link explaining how to do this mod ?
I tried to find it .
Thanks
 

jasonTDI

TDI GURU Vendor , w/Business number
Joined
Apr 26, 2001
Location
Oregon, WI
TDI
20' RAM 3500 CCLB dually HO/Aisan. 2019 Cherokee 2.0T
hammer mod. AND NO!!!!!!!!! DO NOT DO IT!!!!!

You need someone with a vagcom and experience to do this. You could possibly REALLLLLLLLLLY damage the pump. It will not help your 99's start. They need a reflash of the ECU to solve this problem.
 

jcrews

Top Post Dawg
Joined
Jul 28, 2007
Location
Round Rock, TX - VCDS
TDI
All gone
Hamman mod

I don't care for the idea, which is why I replaced the ECM with one that has the correct starting program (RC2).

The idea is simple - disconnect the engine coolant temperature signal when the key is in the start position.

The correct starting program is also in ECM coding 1 automatic transmission. It will work fine for the most part, but there will be a TCM missing signal code (which I don't remember seeing the MIL illuminate for) and the clutch switch will not work. This means some fuel damping software is bypassed and the cruise control won't disable when the clutch is pressed. The starting interlock will still work though.
 

werewolf

Veteran Member
Joined
Jan 2, 2007
Location
wisconsin
TDI
03 New Beetle TDI Jetta,03 & 04 TDI, Golf 04 TDI
Its the Hamm's mod!

You drink a 12-pack of Hamm's beer and fall underneath your TDI to find

your skid plate gone!
 

jasonTDI

TDI GURU Vendor , w/Business number
Joined
Apr 26, 2001
Location
Oregon, WI
TDI
20' RAM 3500 CCLB dually HO/Aisan. 2019 Cherokee 2.0T
That's the up there don'tchaknow hamms mod!
 

Seb500

New member
Joined
Dec 31, 2017
Location
Norwich
TDI
MK5 Golf 2.0 TDI
Does this Hammond mod actually work.
I have a 54 plate Golf 2.0 TDI & a 55 plate Golf TDI the 55 plate is superb with cold and hot starting but the 54 plate takes about 1.5-2 secs to start because of this so called ecu software problem common on 99.5% of 2.0 TDI's
I know a new Bosch Battery will cure the poor hot start as well as a New Starter but only temporary as these parts wear with age surely a relay will last 3 times longer.
I know the ecu needs to see 250rpm from crank sensor before it will squirt fuel in injectors hence with a slower worn starter it might only be 220rpm not enough for a hot start.
Or am I best to forget the relay hammond job and just get a new Starter?
As the Bosch Battery is only 2 years old!!
 
Last edited:

UhOh

Top Post Dawg
Joined
Dec 24, 2014
Location
PNW
TDI
2000 & 2003 Golf GLS (2005 Mercedes E320 CDI)
VE pump in a 2.0L?
 

Mongler98

Top Post Dawg
Joined
Mar 23, 2011
Location
COLORADO (SE of Denver)
TDI
98 Jetta TDI AHU 1.9L (944 TDI swap in progress) I moved so now i got nothing but an AHU in a garage on a pallet.
if your carefull you can hammer mod no issue. it helps 100% to have VAG-COM with vcds though. what engine code?
 

GoFaster

Moderator at Large
Joined
Jun 16, 1999
Location
Brampton, Ontario, Canada
TDI
2006 Jetta TDI
Does this Hammond mod actually work.
I have a 54 plate Golf 2.0 TDI & a 55 plate Golf TDI the 55 plate is superb with cold and hot starting but the 54 plate takes about 1.5-2 secs to start because of this so called ecu software problem common on 99.5% of 2.0 TDI's
I know a new Bosch Battery will cure the poor hot start as well as a New Starter but only temporary as these parts wear with age surely a relay will last 3 times longer.
I know the ecu needs to see 250rpm from crank sensor before it will squirt fuel in injectors hence with a slower worn starter it might only be 220rpm not enough for a hot start.
Or am I best to forget the relay hammond job and just get a new Starter?
As the Bosch Battery is only 2 years old!!
"54 plate" doesn't mean anything to the rest of the world ... we need what model year the car is at a minimum, and preferably what engine it has.

I THINK your engine is a 16-valve "pumpe-duse", which does not have a separate external "Bosch VE" fuel injection pump, and if that's the case, the "hammer" mod is not applicable, not possible, can't be done ... because it only applies to the older engines with an external Bosch VE rotary distributor injection pump.
 

Tdijarhead

Top Post Dawg
Joined
Nov 10, 2013
Location
Lawrenceville PA
TDI
2003 TDI Jetta Daughters Car, 2001 TDI Beetle, Wife’s car, 2005 Golf TDI Mine, all 5 spds
Does this Hammond mod actually work.
I have a 54 plate Golf 2.0 TDI & a 55 plate Golf TDI the 55 plate is superb with cold and hot starting but the 54 plate takes about 1.5-2 secs to start because of this so called ecu software problem common on 99.5% of 2.0 TDI's
I know a new Bosch Battery will cure the poor hot start as well as a New Starter but only temporary as these parts wear with age surely a relay will last 3 times longer.
I know the ecu needs to see 250rpm from crank sensor before it will squirt fuel in injectors hence with a slower worn starter it might only be 220rpm not enough for a hot start.
Or am I best to forget the relay hammond job and just get a new Starter?
As the Bosch Battery is only 2 years old!!

Ok I always thought google was my friend, but even she couldn’t tell me what a 54 or 55 plate Golf is. So, what is it.
 

UhOh

Top Post Dawg
Joined
Dec 24, 2014
Location
PNW
TDI
2000 & 2003 Golf GLS (2005 Mercedes E320 CDI)
So, Owain, are you saying that it increases smoke?:D
 

Fixmy59bug

Veteran Member
Joined
Aug 1, 2009
Location
Las Vegas, NV
TDI
2015 Passat TDI SE
Ok I always thought google was my friend, but even she couldn’t tell me what a 54 or 55 plate Golf is. So, what is it.
It's the age identifier of the vehicle that is built into the European license plate numbering system...

They are the 3rd and 4th digits of the plate number.

With regards to the 3rd digit, A 1 signifies it was first registered sometime between March 1st and August 31st sometime in the 2000's. A 5 signifies it was first registered between Sept 1 and Feb 29 (of the following year) sometime in the 2000's.

The 3rd digits changed to 2's and 6's in the 2010's. And will be 3's and 7's on the 2020's. And so on and so on.

The 4th digit is the year.

So a "53 plate" was first registered some time between Sept 1st, 2003 and Feb 29, 2004.

A "29 plate" will be registered between March 1st, 2019 and August 31st, 2019.

It's a really brilliant numbering scheme.
 

Tdijarhead

Top Post Dawg
Joined
Nov 10, 2013
Location
Lawrenceville PA
TDI
2003 TDI Jetta Daughters Car, 2001 TDI Beetle, Wife’s car, 2005 Golf TDI Mine, all 5 spds
So, Owain, are you saying that it increases smoke?:D
I don’t think he’s saying that at all, I think he’s saying it changes the color and extends tire life.



The 4th digit is the year.

So a "53 plate" was first registered some time between Sept 1st, 2003 and Feb 29, 2004.

A "29 plate" will be registered between March 1st, 2019 and August 31st, 2019.

It's a really brilliant numbering scheme.

Thanks for clearing that up, I suppose I could get used to it, but it just seems easier to say “I have a 2003 car for sale”
 

Hamman

Veteran Member
Joined
Oct 4, 1999
Location
Warren, OH
TDI
No TDI's, but an '84 Rabbit diesel
The real Hamman mod!

Hi all. The mod was one that i came up with for my ALH when it wouldn't start when hot. Chipping provided the ultimate solution, but in the meantime the mod tricked the ECU into thinking the engine was cold and changed the fueling/timing map somewhat. Here is the link to the original thread....

http://forums.tdiclub.com/showthread.php?t=116576&page=3

Hope this helps!
 

UhOh

Top Post Dawg
Joined
Dec 24, 2014
Location
PNW
TDI
2000 & 2003 Golf GLS (2005 Mercedes E320 CDI)
Hi all. The mod was one that i came up with for my ALH when it wouldn't start when hot. Chipping provided the ultimate solution, but in the meantime the mod tricked the ECU into thinking the engine was cold and changed the fueling/timing map somewhat. Here is the link to the original thread....

http://forums.tdiclub.com/showthread.php?t=116576&page=3

Hope this helps!
Sorry, but your name doesn't match!:D

And you came up with it for Pump Duse engines! :D

OK, I'll stop now:D

Couldn't resist. But... been here since 1999 and you're still posting. THAT is pretty awesome!
 

Hamman

Veteran Member
Joined
Oct 4, 1999
Location
Warren, OH
TDI
No TDI's, but an '84 Rabbit diesel
Yeah, it's been a while.....

Somehow along the line, the name of the mod was corrupted. Don't know why.
The ALH is not a pump duse, it's a VE pump, and the car was a 1999.5 Jetta.
 

UhOh

Top Post Dawg
Joined
Dec 24, 2014
Location
PNW
TDI
2000 & 2003 Golf GLS (2005 Mercedes E320 CDI)
Yeah, it's been a while.....

Somehow along the line, the name of the mod was corrupted. Don't know why.
The ALH is not a pump duse, it's a VE pump, and the car was a 1999.5 Jetta.
Sorry, I was being a bit sarcastic (person picking up the thread has a PD engine).
 

Blacktree

Veteran Member
Joined
Sep 9, 2015
Location
Central FL
TDI
'02 Jetta 5-spd
Thanks for the explanation. I see "the hammer mod" mentioned a lot on the forum, but nobody ever describes what it is. It's like a trade secret, or something. Whenever I see it mentioned, I envision someone whacking on their TDI engine with a mallet. :p
 

flee

Veteran Member
Joined
Sep 19, 2011
Location
Chatsworth, CA
TDI
2002 Jetta GLS wagon
Blacktree, The 'Hammer mod' does involve a hammer! It's a physical adjustment
to the IP to reset the injection quantity range.
The 'Hammond mod' is a way to trick the ECM to help overcome hard starting.
 
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