D_jet trouble shooting question - car is home, journey continues, June, update- no more problem-- the fix was simple.... |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
D_jet trouble shooting question - car is home, journey continues, June, update- no more problem-- the fix was simple.... |
DRPHIL914 |
Dec 15 2014, 12:39 PM
Post
#1
|
Dr. Phil Group: Members Posts: 5,768 Joined: 9-December 09 From: Bluffton, SC Member No.: 11,106 Region Association: South East States |
OK. car has been in shop for the past week, and today Bob spent several hours on it but what he found was when the MPS is disconnected from the vac hose it will idle and run, but when it gets connected it goes immediately lean and dies, and will not run with that hose on there- the MPS holds Vac no loss of pressure, but that doesnt mean that its not bad.
1- i thought that if an MPS went bad it defaulted rich? but when this is getting vac it goes lean right away and dies. but it will run and idle with out the vac , the AF meter then shows 9.8-10.2 or so which is of course rich but not flooding out. so the question is why is it going lean when hooked up? when this issue started about 2 weeks ago, it had been running just fine and all of a sudden it quit running. 2. could there be another issue we dont see that would be making it way to lean other than the MPS? might need to test another MPS, my 2nd one i just bought from someone here and it has never been opened but will not hold vac (slowly looses vac pressure) so it probably need to be opened and re-sealed. not a good candidate to trouble shoot with. ------ FYI- 1975 d-jet 2.0. newer wiring harness , CHT is newish(replaced 2 months before this issue started and was running perfect at that time) |
DRPHIL914 |
Dec 18 2014, 11:21 PM
Post
#2
|
Dr. Phil Group: Members Posts: 5,768 Joined: 9-December 09 From: Bluffton, SC Member No.: 11,106 Region Association: South East States |
Picked up the car tonight and drove it home.
A/F meter reading high I think. Idle at warm is 13, under part load is between 14.5- 15; or so. That seems too lean but it did go well . Now.it will be interesting to see how the other one that is being sent to me reads. |
ChrisFoley |
Dec 19 2014, 07:13 AM
Post
#3
|
I am Tangerine Racing Group: Members Posts: 7,934 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None |
Picked up the car tonight and drove it home. A/F meter reading high I think. Idle at warm is 13, under part load is between 14.5- 15; or so. That seems too lean but it did go well . Now.it will be interesting to see how the other one that is being sent to me reads. Under light load you should be leaner than that, but when you tip into the throttle it should go rich - 13.2 to 12.5. |
DRPHIL914 |
Dec 19 2014, 02:22 PM
Post
#4
|
Dr. Phil Group: Members Posts: 5,768 Joined: 9-December 09 From: Bluffton, SC Member No.: 11,106 Region Association: South East States |
Picked up the car tonight and drove it home. A/F meter reading high I think. Idle at warm is 13, under part load is between 14.5- 15; or so. That seems too lean but it did go well . Now.it will be interesting to see how the other one that is being sent to me reads. Under light load you should be leaner than that, but when you tip into the throttle it should go rich - 13.2 to 12.5. That's where I was before it went bad. I'm going to try to get this one adjusted to a better mix . I have 2 of the rebuild kits from the group buy so I'm going to go ahead and find out if I can make one of the other ones work. I will do some comparison with the one from kent, Nad another one that I will be testing and purchase it it tests out good - that one is an unmolested one so I what to see where the numbers on these are. Phil |
Lo-Fi Version | Time is now: 5th June 2024 - 11:11 PM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |