I'm in the middle of chasing a "typical" warm rich idle problem and I noticed my MPS part # is different that any listed on Paul Anders' website. Is this really critical? I ask because i've been spending the past 2 weekends looking for vacuum leaks & electrical shorts/breaks to no scuccess. (but thats not to say i'm totally convinced i dont have any). Now i'm confused as to where i should direct my attention.

I have a '73 1.7 and currently my MPS is:
Bosch # 0 280 100 007
VW # 311 906 051 C

RUSS

(oh yeah, i am confident my timing and valves are set)

I dont recogniz ethay #, the 1.7, last set of numbers should be 049. maybe thats an early MPS..?? How is your CHT resistence?

yeah, I have one of those sitting in a box. Looks like a real early 1.7L one to me. Maybe has a different spring tension, who knows as I haven't had time to check it yet.

The 049 is the correct MPS for a 1.7L 73 914.

I can try to get to it tomorrow and see what is different.
I am all oily from finishing the gear swap out in my tranny, sorry
As for the rich idle, check your MPS for holding 15hg of vacuum for 5 minutes. If its a leaker that could be your problem

Geoff

CHT resistence seems fine... both at the unit itself and thru a cold wiring harness. (at some point I plan to test the various resistences w/ a warm harness just in case there's something funny going on there)

I've also thought a vac test on the MPS would be a good idea... but whats the best way for an average joe to do that? What kind of tool is easiest to make that happen? (can i McGuiver a turkey baster?)

thanks for the help.
RUSS

Bosch # 0 280 100 007

My Bosch book says this fits a 1970 and 1971 T3.

Gotta get a Mityvac for the vac test.

The one I have specs out to be fairly rich at idle for a 914, at part load & WOT set up for a 73 2.0L. If you are using this in a 1.7L it would be too rich across the board.
Get a 049.

Geoff

Rich? That seems odd. Wasn't the T3 a 1600cc engine? I would think it would make a 1700cc engine run lean.

I don't know what the injector flow rates are for the T-3 which probably is smaller that even the 1.7L. All I know this sealed unit is:
15hg-.82
4hg-1.26
0hg-1.55
These are the numbers on the Wavetek which at sealevel is about where a 037MPS is.This is a richer setting than the 049 MPS (larger numbers equals richer mix).

Geoff

Wow, way rich allright...

Thanks guys!
I know one of the P.O.s was the owner of a VW shop and it wouldnt be the first time he did a "clever" substitution.

I'll definitely start shopping for an 049. Whats the best/ most cost effective way to go about shopping for an MPS?
I'll have to wait and see how much that improves the situation. In the meantime i'll continue my vac leak & short checklist, just to rule out anything else.

The resources on this bbs continue to amaze me. I dont know how long it would have taken me to figure that out on my own or via word of mouth. Thanks again.

RUSS

I believe the type 3 used the same yellow injectors as the 1.7's did, FWIW