How do you fix a 1.8 w Ljet, that is running too lean |
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How do you fix a 1.8 w Ljet, that is running too lean |
jsayre914 |
May 12 2011, 04:20 PM
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#1
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Speed Up !!! Group: Members Posts: 3,206 Joined: 10-February 08 From: Timonium MD 21093 Member No.: 8,696 Region Association: MidAtlantic Region |
After seeing the inside of my head, it seems that I have a lean condition. What causes the Lean condition and how can I fix it?
1.8 bone stock with L-jet (IMG:style_emoticons/default/popcorn[1].gif) |
Als914 |
May 12 2011, 05:35 PM
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#2
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Lighting my way Group: Members Posts: 330 Joined: 1-January 06 From: Hemet,Ca. Member No.: 5,346 Region Association: Southern California |
You can make an adjustment at the airflow meter under the black cover where the swing arm contacts the carbon track.
I will see if I can locate the instructions I used. BTW I adjusted my air flap setting and it made some pretty impressive acceleration improvements. Al |
jcd914 |
May 12 2011, 05:49 PM
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#3
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Advanced Member Group: Members Posts: 2,081 Joined: 7-February 08 From: Sacramento, CA Member No.: 8,684 Region Association: Northern California |
There is a mixture adjustment screw on the air flow meter. It works by opening or closing a bypass so more or less air flows past the flap in the air flow meter. It's enfluence is primarly at idle and low speed.
Before you pop the top off your air flow meter and start adjusting the wiper and/or spring make sure you don't have vacuum leaks and the engine is tuned properly (pts, plugs, valve adjustment, etc...). It took me seveal days working on it to get the air flow meter adjusted back close to stock after someone had "fixed" on my VW bus. Jim |
SLITS |
May 12 2011, 06:03 PM
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#4
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"This Utah shit is HARSH!" Group: Benefactors Posts: 13,602 Joined: 22-February 04 From: SoCal Mountains ... Member No.: 1,696 Region Association: None |
Raise the fuel pressure ....
I would also assume that the 1.8L & "75-'76 2.0L engines were set up leaner for emissions purposes. |
Cap'n Krusty |
May 12 2011, 06:37 PM
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#5
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Cap'n Krusty Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
The bypass screw in the air box affects only the idle mixture. The fuel pressure isn't adjustable, except for the vacuum applied to the diaphragm under acceleration. It has a "rising rate" fuel pressure regulator. If there were air leaks, it wouldn't start. The big risk in resetting the spring tension in the airbox is getting it to be correct under a range of conditions. It can be done, but it actually requires a fixture and a way to read the injector opening in milliseconds to calibrate the opening vs. the enrichment. That's if you want to do it right. Running too rich has consequences for the driveability.
I'd look at the distributor, making sure the vacuum capsule works properly, and make sure the timing is correct USING THE PROPER TIMING PROCEDURE, which is far different than the procedure used on the D-jet cars. The Cap'n |
Rockaria |
May 12 2011, 07:56 PM
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#6
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ZippidyDoDah... Group: Members Posts: 817 Joined: 2-May 03 From: Southwest, USA Member No.: 645 Region Association: None |
Before you start making adjustments, take off the rubber boot between the AFM and Throttle. Check it carfully for cracks. They hide and are hard to see. I found that this was my main source of Lean condition on my L-Jet. Small cracks that leaned it out but not large enough to cause too much trouble.
Since fuel pressure is also set by vacuum on the l-jet, adjusting the AFM is your best bet. It is super easy to do under the black cover. |
jsayre914 |
May 12 2011, 08:17 PM
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#7
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Speed Up !!! Group: Members Posts: 3,206 Joined: 10-February 08 From: Timonium MD 21093 Member No.: 8,696 Region Association: MidAtlantic Region |
thanks for the replies (IMG:style_emoticons/default/beerchug.gif)
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McMark |
May 12 2011, 09:25 PM
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#8
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914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
I had a 912E come into the shop awhile back. The goal was to make it squeak past SMOG. After checking everything, swapping in some rebuilt components from Fuel Injection Corp, and replacing some seals it passed the test better than it had in 10 years. My point is that fixing the system is the best way to make it run the way it should. You should have to 'trick' it. (IMG:style_emoticons/default/wink.gif)
Good luck! |
messix |
May 12 2011, 09:37 PM
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#9
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AKA "CLUTCH KILLER"! Group: Members Posts: 6,995 Joined: 14-April 05 From: between shit kickers and pinky lifters/ puget sound wa.north of Seattle south of Canada Member No.: 3,931 Region Association: Pacific Northwest |
check all the vacuum lines, see if the ends are hard and cracking. get new ones or trim a bit off the ends if theres enough to do so. L-jet is so picky on vacuum leaks and will run like shit if you have i little leak and run poor if theres a tiny leak.
check dwell and timing too. |
Dave_Darling |
May 13 2011, 12:07 AM
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#10
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914 Idiot Group: Members Posts: 15,063 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California |
L-jet + lean == vacuum leak, almost always.
--DD |
Root_Werks |
May 13 2011, 08:10 AM
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#11
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Village Idiot Group: Members Posts: 8,505 Joined: 25-May 04 From: About 5NM from Canada Member No.: 2,105 Region Association: Pacific Northwest |
L-jet + lean == vacuum leak, almost always. --DD (IMG:style_emoticons/default/agree.gif) L-Jet is crazy sensative to vacuum leaks. Even the valve covers are critical to get 100% sealed. 99% sealed on L-Jet will make it run incorrectly. Check everything, as others have said, replace hoses. Also, the oil filler has to be 100% sealed, the cork gasket at the base has to be soft and 100% sealed. I wouldn't adjust anything, just seal the system up. |
mepstein |
May 13 2011, 09:24 AM
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#12
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914-6 GT in waiting Group: Members Posts: 19,643 Joined: 19-September 09 From: Landenberg, PA/Wilmington, DE Member No.: 10,825 Region Association: MidAtlantic Region |
Come by and pick up my 1.8 with 80K. It's complete. Free for Joe S. (IMG:style_emoticons/default/biggrin.gif)
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type47 |
May 14 2011, 11:43 AM
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#13
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Viermeister Group: Members Posts: 4,254 Joined: 7-August 03 From: Vienna, VA Member No.: 994 Region Association: MidAtlantic Region |
Come by and pick up my 1.8 with 80K. It's complete. Free for Joe S. (IMG:style_emoticons/default/biggrin.gif) Yea! Plug 'n play (IMG:style_emoticons/default/smilie_pokal.gif) |
jsayre914 |
May 16 2011, 09:24 PM
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#14
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Speed Up !!! Group: Members Posts: 3,206 Joined: 10-February 08 From: Timonium MD 21093 Member No.: 8,696 Region Association: MidAtlantic Region |
Come by and pick up my 1.8 with 80K. It's complete. Free for Joe S. (IMG:style_emoticons/default/biggrin.gif) (IMG:style_emoticons/default/huh.gif) Not sure how I missed this post. (IMG:style_emoticons/default/laugh.gif) PM on its way (IMG:style_emoticons/default/pray.gif) |
jsayre914 |
May 16 2011, 09:24 PM
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#15
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Speed Up !!! Group: Members Posts: 3,206 Joined: 10-February 08 From: Timonium MD 21093 Member No.: 8,696 Region Association: MidAtlantic Region |
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Drums66 |
May 17 2011, 11:56 AM
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#16
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914 Rudiments Group: Members Posts: 5,321 Joined: 15-January 03 From: Coronado,Cali Member No.: 151 Region Association: Southwest Region |
There is a mixture adjustment screw on the air flow meter. It works by opening or closing a bypass so more or less air flows past the flap in the air flow meter. It's enfluence is primarly at idle and low speed. Jim ......You can do this but.........I wouldn't go under the lid(Real pros..say don't) (IMG:style_emoticons/default/idea.gif) (IMG:style_emoticons/default/bye1.gif) (IMG:style_emoticons/default/popcorn[1].gif) (IMG:style_emoticons/default/popcorn[1].gif)(unless you really know what you are doing) |
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