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| era vulgaris |
Aug 27 2014, 02:04 PM
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#1
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J is for Genius ![]() ![]() ![]() Group: Members Posts: 986 Joined: 10-November 13 From: Raleigh, NC Member No.: 16,629 Region Association: South East States |
My car has developed an extremely annoying bucking under acceleration. It started about a week ago, and at first it would only happen while accelerating out of a fast turn. But now it does it all the time while accelerating. It's like the car is oscillating between half power and full power, making it lurch-slow-lurch-slow-lurch-slow. It's like you're riding a bucking bronco or something. The only cure seems to be to get off the throttle completely, upshift, then slowly accelerate.
Anyone have any idea where I should start looking first? |
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| r_towle |
Sep 2 2014, 09:47 PM
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#2
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Custom Member ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 24,705 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States
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I would suggest a few things.
A new fuel tank sock on the return line at the fuel tank... Check all your fuel lines. Check all your wiring, make sure all the fuel injection wiring is properly connected and not loose...it happens. Do new points, new plugs, and new wires, rotor and distributor cap. Remove the advance plates and clean then inside the distributor...40 year old grease is like glue now... Remove the if trigger points and blow out all the crap from the bottom of the distributor. Full tune up Set valves Set dwell Set timing Check fuel pressure. Now you would have eliminated a large number of variables...it's just a good place to start. |
| era vulgaris |
Sep 3 2014, 09:05 AM
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#3
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J is for Genius ![]() ![]() ![]() Group: Members Posts: 986 Joined: 10-November 13 From: Raleigh, NC Member No.: 16,629 Region Association: South East States |
I would suggest a few things. A new fuel tank sock on the return line at the fuel tank... Check all your fuel lines. Check all your wiring, make sure all the fuel injection wiring is properly connected and not loose...it happens. Do new points, new plugs, and new wires, rotor and distributor cap. Remove the advance plates and clean then inside the distributor...40 year old grease is like glue now... Remove the if trigger points and blow out all the crap from the bottom of the distributor. Full tune up Set valves Set dwell Set timing Check fuel pressure. Now you would have eliminated a large number of variables...it's just a good place to start. Plugs, wires, cap, rotor are all only a few months old. I've put in a new pertronix elec ignition and flame thrower coil also. FI wiring has been gone through and all contact points cleaned. Valve adjustment, timing, and dwell has been done in the last couple months. All FI hoses are only a few months old, and routed correctly. Injectors are all recently rebuilt - all bought here from a couple different forum members. All 4 elbow hoses are new. The rest of the fuel hoses are relatively new (I didn't install them, but they're definitely not OE.) I plan on having the fuel tank cleaned and a new sock installed by a local air-cooled shop here in town. Is there a good guide somewhere to pulling and cleaning the dizzy? This is really the only other thing I haven't done. |
era vulgaris car is bucking under acceleration...any ideas? Aug 27 2014, 02:04 PM
Mike Bellis sounds like a lack of fuel. Aug 27 2014, 02:50 PM
jt914-6 When you get the bucking worked out check your mot... Aug 27 2014, 03:23 PM
Rand Don 't know if the TPS would cause bucking to ... Aug 27 2014, 03:45 PM
wndsnd Car still have the Djet?
Has the tank ever been c... Aug 27 2014, 03:45 PM
era vulgaris Motor mounts and trans mounts are still good.
TPS... Aug 27 2014, 04:32 PM
brp986s
Motor mounts and trans mounts are still good.
TP... Aug 27 2014, 07:31 PM
era vulgaris Any chance a dying fuel pump would cause this?
Ju... Aug 27 2014, 04:52 PM
Mike Bellis
Any chance a dying fuel pump would cause this?
J... Aug 27 2014, 06:52 PM
scotty b Check all of the vaccum lines. there is one in par... Aug 27 2014, 07:18 PM
jasons When my 2.0 did this, it was the trigger points in... Aug 27 2014, 07:21 PM
mepstein Mine did this. Did a LOT of things to try to fix b... Aug 27 2014, 07:52 PM
warrenoliver Could be a loose ground wire on your distributor p... Aug 27 2014, 09:16 PM
era vulgaris
Check all of the vaccum lines. there is one in pa... Aug 27 2014, 09:44 PM
BeatNavy
I think it's probably worth reading this thre... Aug 28 2014, 04:30 AM
76-914 What's your fuel pressure? Aug 27 2014, 09:46 PM
The Cabinetmaker I'm surprised that no one has mentioned the f... Aug 28 2014, 04:03 AM
dknechtly There's a lot of good advice here. Make sure ... Aug 28 2014, 07:55 AM
era vulgaris So first I cleaned every contact I could find in b... Aug 28 2014, 01:29 PM
Phoenix914 :headbanger: :Qarl: :driving: Aug 28 2014, 03:43 PM
The Cabinetmaker don't you love the simple fixes Aug 28 2014, 04:19 PM
era vulgaris Definitely! :Qarl: Aug 28 2014, 04:40 PM
era vulgaris Celebrated too soon :(
Went for another drive t... Aug 28 2014, 09:44 PM
PancakePorsche
Celebrated too soon :(
Went for another drive ... Aug 29 2014, 02:33 AM
era vulgaris Got a friend bringing over his fuel pressure gauge... Sep 2 2014, 05:35 PM
Rand
Disregard that since you have a carb now. You don... Sep 2 2014, 06:20 PM
era vulgaris
Disregard that since you have a carb now. You do... Sep 2 2014, 07:12 PM
BeatNavy
Is there a good guide somewhere to pulling and c... Sep 3 2014, 09:22 AM
era vulgaris
I say again (from page 1 of this thread), you may... Sep 3 2014, 10:49 AM
BeatNavy
[quote name='BeatNavy' post='2081511' date='Sep 3... Sep 3 2014, 01:24 PM
914_teener
I would suggest a few things.
A new fuel tank soc... Sep 2 2014, 10:22 PM
era vulgaris
Couple of extra things I thought of:
Check your... Sep 3 2014, 09:08 AM
914_teener :agree:
I assumed you had already done this.
Ge... Sep 3 2014, 09:47 AM
BeatNavy Sorry, a couple more things to note: you probably... Sep 3 2014, 02:08 PM
era vulgaris
Sorry, a couple more things to note: you probabl... Sep 3 2014, 04:05 PM
BeatNavy
Sorry, a couple more things to note: you probab... Sep 3 2014, 04:18 PM
jacksun hi, maybe the below will help?
"Throttle Swi... Sep 3 2014, 07:52 PM
era vulgaris Aha! i finally got it. After a couple weeks ... Sep 15 2014, 11:47 AM
BeatNavy
check the obvious shit first before diving into t... Sep 15 2014, 11:56 AM
era vulgaris
But at least you learned a lot of things that co... Sep 15 2014, 01:10 PM
dknechtly Geesh, thanks for posting the solution. That... Sep 15 2014, 12:16 PM![]() ![]() |
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