 Which way to turn, To make it run a little rich? |
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| KaptKaos |
 Apr 9 2005, 03:11 PM
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#1
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Family  Group: Members Posts: 4,009 Joined: 23-April 03 From: Near Wausau Member No.: 607 Region Association: Upper MidWest  |
Stock 73, 1.7 with FI. Seems to be running a little lean. Which way do I turn the knob on the brain to make it run a little richer? I certainly do not want to over do this, just a slight adjustment, so how far should I turn it?
Thanks, Joe |
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Replies(1 - 16)
| scotty914 |
Apr 9 2005, 03:22 PM
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#2
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suby torque rules Group: Members Posts: 1,525 Joined: 20-July 03 From: maryland, the land of 25 year Member No.: 924 |
the ecu knob only does idle, if you want it richer across the whole range put a 100 ohm resistor in line with the cht
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| anthony |
Apr 9 2005, 04:42 PM
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#3
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2270 club Group: Benefactors Posts: 3,107 Joined: 1-February 03 From: SF Bay Area, CA Member No.: 218  |
How are you determining that it is running lean?
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| Bleyseng |
Apr 9 2005, 05:02 PM
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#4
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Aircooled Baby! Group: Members Posts: 13,035 Joined: 27-December 02 From: Seattle, Washington (for now) Member No.: 24 Region Association: Pacific Northwest |
I am wondering too???
(IMG:http://www.914world.com/bbs2/html/emoticons/agree.gif) This I wanna hear.. |
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| mike_the_man |
Apr 9 2005, 05:13 PM
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#5
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I like stuff! Group: Members Posts: 1,338 Joined: 11-June 03 From: Regina, Saskatchewan, Canada Member No.: 809 |
Right is richer, left is leaner. But listen to all the other guys first. How do you know it's lean, and know that turning the knob on the ECU only adjusts idle mixture.
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| Aaron Cox |
Apr 9 2005, 06:51 PM
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#6
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Professional Lawn Dart Group: Retired Admin Posts: 24,541 Joined: 1-February 03 From: OC Member No.: 219 Region Association: Southern California |
im sure he has a wide band O2 sensor right joe?
(IMG:http://www.914world.com/bbs2/html/emoticons/lol2.gif) |
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| KaptKaos |
Apr 9 2005, 07:03 PM
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#7
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Family Group: Members Posts: 4,009 Joined: 23-April 03 From: Near Wausau Member No.: 607 Region Association: Upper MidWest |
/whap No Aaron, I don't have an O2 sensor. (IMG:http://www.914world.com/bbs2/html/emoticons/chair.gif) I'll tell you what you can stick in my tail pipe.... ah, nevermind. Anyway, getting a little backfiring when cold. Cold start injector is not connected, so its not surprising. Just starting to a very infrequent hesitation at speed. Went to go pull the plugs today to look for signs there, but the kids got into the way. FYI - I generally do not go off half-cocked and start playing with stuff. My general process is to gather as much info as I can. This way I am fully cocked before I screw it up. (IMG:http://www.914world.com/bbs2/html/emoticons/wink.gif) |
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| anthony |
Apr 9 2005, 08:31 PM
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#8
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2270 club Group: Benefactors Posts: 3,107 Joined: 1-February 03 From: SF Bay Area, CA Member No.: 218 |
Around 3,000 rpms when crusing? Most likely culprit is the TPS if it hasn't been swapped out in a million years. |
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| TheCabinetmaker |
Apr 9 2005, 08:39 PM
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#9
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I drive my car everyday Group: Members Posts: 8,301 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
What he said. Worn Tps cuts off the fuel for a split second. Brad Anders says that is the only thing that will cause "bucking" at cruising speeds. My limited experience agrees with him. Unplug it and see if it goes away. It won't idle very well, and it won't accelerate very well, but it will cruise perfectly. |
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| KaptKaos |
Apr 9 2005, 09:27 PM
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#10
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Family Group: Members Posts: 4,009 Joined: 23-April 03 From: Near Wausau Member No.: 607 Region Association: Upper MidWest |
Doh!
Forgot one more symptom. After running for a while, if I come to a stop, the car will really bog down in first. Almost like it is going to stall. Once it gets about 1800-1900 RPM it goes just fine. Still the throttle switch? |
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| Trekkor |
Apr 9 2005, 09:46 PM
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#11
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I do things... Group: Members Posts: 7,809 Joined: 2-December 03 From: Napa, Ca Member No.: 1,413 Region Association: Northern California |
Check fuel pressure.
Increase to enrichen. KT |
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| double-a |
Apr 9 2005, 11:10 PM
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#12
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Senior Member Group: Members Posts: 987 Joined: 15-September 03 From: vancouver, wa, usa Member No.: 1,162 Region Association: Pacific Northwest |
my car is doing this, 1.8 liter l-jet engine, does the same random "hesitation" or "bucking" at speed. it's been driving me nuts.
what's a tps??? ~a |
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| TheCabinetmaker |
Apr 10 2005, 08:37 AM
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#13
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I drive my car everyday Group: Members Posts: 8,301 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
Tps= throttle positioning switch. I know nothing about the L jet, so don't know if you have one or not.
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| double-a |
Apr 10 2005, 10:33 PM
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#14
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Senior Member Group: Members Posts: 987 Joined: 15-September 03 From: vancouver, wa, usa Member No.: 1,162 Region Association: Pacific Northwest |
yup, got a tps. i pulled it and cleaned it, car still stutters a little.
~a |
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| swood |
Apr 10 2005, 10:51 PM
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#15
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Senior Member Group: Members Posts: 1,839 Joined: 6-February 03 From: Strong Beach Member No.: 251 Region Association: None |
Small Vacuum leak? That'll cause a lot of problems too.
Do you have all the L-Jet manuals? There are numerous ones available. |
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| scotty914 |
Apr 10 2005, 11:18 PM
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#16
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suby torque rules Group: Members Posts: 1,525 Joined: 20-July 03 From: maryland, the land of 25 year Member No.: 924 |
on a l jet a stutter can be 2 things, one the dizzy is not adavncing right or its sticking. i would pull it clean it and make sure you set the timing right. the second thing is the flapper has a varible resistor in it. you should pull it and hook up an ohm meter to it and push it through its range to see if it has a worn spot.
while you are in there you should check the fuel pressure, on a l jet it changes with vacumn. it could be the fuel pressure not doing what it should. |
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| Cap'n Krusty |
Apr 10 2005, 11:31 PM
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#17
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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 |
You misunderstand the function and operation of the cold start valve. It has to be REALLY cold, and it ONLY operates when the starter is engaged. You're NOT gonna get backfiring because of the CSV. The Cap'n |
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