after install of switch to fix "hard start" CEL and new rattle?

nostopin

Active member
Joined
Jun 24, 2011
Location
Emerald Triangle, Nor Cal
TDI
99.5 Jetta GL TDI
99.5 jetta TDI 137k mi 5spd. I was having a hell of a time with the "hard start when warm" prob, so the dealer sent it to a non VW mechanic to try a diff(used) injection pump. didnt help so they put the old one back in. while they were doing that I learned about the "resistor switch" method of fixing this. I added a 1/4W 3300Ohm resistor across a momentary push button normally closed switch and added it to the circuit on the #3 terminal (blue wire) It starts GREAT. half a turn and its running. Before it took a good 10 revs to fire. The original post stated he used a 10kOhm resistor, but I found later posts saying 10k will make it think its to cold and start the glowplugs on a long cycle 4700Ohm will start a short cycle, and 3300Ohm will not start a glowplug cycle. so I went with 3300.

The next day I drive 44mi to work, everything is coo. After work on my way home, about 15mi into the commute my CEL comes on. I quickly turn off the radio and roll down all the windows. I hear nothing alarming or out of the ordinary, I know the oil is fine. I pull over and shut it down to take a look. everything looks in order. when I started it back up I used the button and it still works, so it must still be connected. while idling I hear a new rattling noise. MIGHT be new? I dont know. maybe that CEL multiplied my senses x10 drove the rest of the way home. no diff in power, no smoke, didnt see the fuel gauge drop (why i love this car) If anyone else has experienced a CEL after their switch install, what was it? did you find any problems? I'm going to go today and try to get it hooked up to a VCDS to see what the dealio is.
 

nostopin

Active member
Joined
Jun 24, 2011
Location
Emerald Triangle, Nor Cal
TDI
99.5 Jetta GL TDI
Well I hooked her up to a OBD-II scanner and found the CEL was just the temp sensor. Maybe the rattle was in my head.

Supposedly the resistor is to keep the computer from turning on the CEL thinking it is still hooked up properly. Maybe I went to low of resistance? out of the normal range or something? I'll try another resistor and see if it fixes it.
 

Corsair

Veteran Member
Joined
Aug 17, 2003
Location
Weedsport, New York
TDI
2002 Jetta GLS TDI 5M
while idling I hear a new rattling noise
If I understand correctly, this is shortly after someone (dealer or private mechanic) swapped out the injection pump (then back..)

ie. the timing belt system has been recently manipulated. Did they change all the requisite components ? (some of them, maybe twice)??

Gulpppp....
 

nostopin

Active member
Joined
Jun 24, 2011
Location
Emerald Triangle, Nor Cal
TDI
99.5 Jetta GL TDI
ya, that was my concern. The car lot sent it to "their" mechanic who is NOT a TDI guy. The dealer and the Mechanic had some deal worked out. Mechanic quoted the dealer 1.5 hours to do the I.P. 10 days later I got it back lol. So since the mechanic missed out on TONS of $ due to the misquote, he offered to put a new TB on for me for ONLY another $800. I told him no thanks, the receipts say it was just done 20k mi ago.
I do have every intention of changing it soon either by the local Euro performance guy, or myself if I can acquire the tools soon. At that time I just wanted to get it as far away from that shop as I could. 10 days to swap a IP, I kinda wanted to go down there and put it back together myself.
 

nostopin

Active member
Joined
Jun 24, 2011
Location
Emerald Triangle, Nor Cal
TDI
99.5 Jetta GL TDI
Oh and update on the CEL. Its off now, stays off, and the bulb isn't burnt out. Strange, I know. last night and today it just stopped coming on. I have changed nothing to get this result But its coo with me. I cant stand a CEL. like nails on a chalkboard, socks and sandals, etc.
 
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