Adjusting Air / Fuel Mixture |
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Adjusting Air / Fuel Mixture |
sjhenry1075 |
Jun 22 2021, 08:29 AM
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#1
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Member Group: Members Posts: 268 Joined: 22-July 12 From: Stevensville, MD Member No.: 14,709 Region Association: North East States |
Hey everyone, please excuse my lack of knowledge on this subject, but I have a question regarding air / fuel mixture adjustment on my 71 1.7 with stock D-jet. I posted this question on Facebook but wanted to try here as well.
Back story: my car will only idle and drive when both vacuum lines are disconnected from the distributor. When connected (I used a diagram found on 914world so I know they aren't flipped) the car barely idles when cold or warm, and it is almost undriveable; it surges, bucks, and hesitates. If I remove both vacuum lines from the distributor it idles and runs great. From what I understand from the replies on FaceBook, this could be an air/fuel mixture issue, but how is that adjusted with for the 71? Is there a certain procedure for this? Thanks in Advance for any assistance you can provide! For those going to PA for the Northeast gathering, I'm looking forward to meeting you! |
brant |
Jun 22 2021, 08:41 AM
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#2
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914 Wizard Group: Members Posts: 11,638 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
you have to verify everything is correct before you adjust AFR
it almost sounds like a timing issue or the advance plate not working freely after checking timing, fuel pressure, valves, etc. then you will need to read the MPS articles on here and also the brad anders website buy a wide band O2 sensor and hook it up to a display of some sort... either hand held, gauge, or lap top in the car. you'll have to clean the epoxy sealant out of of the MPS cap buy the tool for adjustment from CFR... and a new membrane if you don't pass the vacuum test of the MPS then there are 3 adjustments in the MPS this can not be accomplished with a wavetech (on the bench) or an AFR on the road they adjust 3 ranges of RPM (WOT, etc) brant |
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