Tach drops in RPM with brake pedal |
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Tach drops in RPM with brake pedal |
boxstr |
Mar 11 2009, 11:25 PM
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#1
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MEMBER:PACIFIC NORTHWEST REGION Group: Members Posts: 7,522 Joined: 25-December 02 From: OREGON Member No.: 12 Region Association: Pacific Northwest |
Okay I cannot for the life of me remember what the problem is???
Seems like I have run across this before. Step on the brake pedal and the RPM on the tach needle drops? Severe volt drop when brakes are applied and or the lights are turned on. |
southernmost914 |
Mar 12 2009, 04:35 AM
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#2
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KEY WEST/HAVANA Tunnel Authority Group: Members Posts: 338 Joined: 16-October 07 From: Key West/ St. Augie, Fl USA Member No.: 8,234 Region Association: South East States |
"Tach drops in RPM with brake pedal"
Press in the clutch. (IMG:style_emoticons/default/av-943.gif) (IMG:style_emoticons/default/av-943.gif) I had the same problem when the main ground behind the fuse block worked loose. (IMG:style_emoticons/default/bye1.gif) Steve |
6freak |
Mar 12 2009, 10:48 AM
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#3
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MR.C Group: Members Posts: 4,740 Joined: 19-March 08 From: Tacoma WA Member No.: 8,829 Region Association: Pacific Northwest |
Yes bad ground
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surfcity914 |
Mar 12 2009, 11:28 AM
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#4
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Newbie Group: Members Posts: 4 Joined: 31-July 06 From: Huntington Beach, CA Member No.: 6,547 |
Can someone please post pictures or describe exactly where the ground points to be checked are located? Thanks.
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southernmost914 |
Mar 12 2009, 11:37 AM
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#5
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KEY WEST/HAVANA Tunnel Authority Group: Members Posts: 338 Joined: 16-October 07 From: Key West/ St. Augie, Fl USA Member No.: 8,234 Region Association: South East States |
Can someone please post pictures or describe exactly where the ground points to be checked are located? Thanks. Start with these: Front fender wells behind headlights. Left and right. Behind fuse block under dash. Next to relay board in engine compartment. Battery ground strap. Transmission ground strap. (IMG:style_emoticons/default/bye1.gif) Steve |
rhodyguy |
Mar 12 2009, 11:45 AM
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#6
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,080 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
occurs when brakes are applied. i spoke with craig. something to do with the illumination system in the rear. i imagine a +wire was attached to a ground terminal. some shop told the owner that a new harness was required. wow.
k |
pktzygt |
Mar 12 2009, 12:15 PM
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#7
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Member Group: Members Posts: 328 Joined: 20-March 07 From: Chesapeake, VA Member No.: 7,611 Region Association: MidAtlantic Region |
Okay I cannot for the life of me remember what the problem is??? Seems like I have run across this before. Step on the brake pedal and the RPM on the tach needle drops? Severe volt drop when brakes are applied and or the lights are turned on. This problem isn't on the black '73 with the tan interior and riveras is it? |
brp986s |
Mar 12 2009, 10:06 PM
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#8
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Member Group: Members Posts: 434 Joined: 27-September 07 From: los angeles Member No.: 8,167 |
When I had this symptom, fuse 9 would also blow. Unfortunately, about half the car's electrical system goes thru this fuse so there are many possibilities. Also, many of these things meet at the hazard switch. The way I tracked mine down was to put a fuse and ammeter in-line with the fuse 9 terminals. Then operate various controls (turn left...turn right...brake...etc) until hopefully you find something that pulls inordinate current or blows the fuse. If it's an intermittant short, it can be a real (IMG:style_emoticons/default/headbang.gif) ....lotsa luck
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SGB |
Mar 12 2009, 10:17 PM
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#9
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just visiting Group: Members Posts: 4,086 Joined: 8-March 03 From: Huntsville, AL Member No.: 404 Region Association: South East States |
I think maybe I would check the brake lights first too see if they are shorting when the brakes are applied...
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JoeSharp |
Mar 12 2009, 10:26 PM
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#10
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In Irvine, Ca. May 15-18 Group: Members Posts: 3,947 Joined: 9-July 03 From: DeLand, Florida Member No.: 898 Region Association: South East States |
My 72 had a ground at the rear trunk latch. It screwed with the turn signals but I would check the grounds under the dash.
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Borderline |
Mar 12 2009, 10:44 PM
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#11
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Senior Member Group: Members Posts: 720 Joined: 8-February 05 From: San Juan Bautista, CA Member No.: 3,577 Region Association: Northern California |
I have the same problem plus the tach drops with the headlights turned on and also fluctuates with the turn signals. I've checked all the grounds I can find...please help us. (IMG:style_emoticons/default/headbang.gif)
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oldschool |
Mar 13 2009, 12:28 AM
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#12
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Advanced Member Group: Members Posts: 3,362 Joined: 29-October 08 From: P-town Member No.: 9,705 Region Association: Southern California |
Okay I cannot for the life of me remember what the problem is??? Seems like I have run across this before. Step on the brake pedal and the RPM on the tach needle drops? Severe volt drop when brakes are applied and or the lights are turned on. I had the same thing about to me also, and the generator light would go on also. it was a bad fuse. play with the fuse box. |
computers4kids |
Mar 13 2009, 08:30 AM
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#13
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Love these little cars! Group: Members Posts: 2,443 Joined: 11-June 05 From: Port Townsend, WA Member No.: 4,253 Region Association: None |
I've also seen the incorrect bulb in the brake lights/tailights do some amazingly weird things.
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oldschool |
Mar 13 2009, 10:11 AM
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#14
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Advanced Member Group: Members Posts: 3,362 Joined: 29-October 08 From: P-town Member No.: 9,705 Region Association: Southern California |
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rick 918-S |
Mar 13 2009, 10:26 AM
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#15
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Hey nice rack! -Celette Group: Members Posts: 20,456 Joined: 30-December 02 From: Now in Superior WI Member No.: 43 Region Association: Northstar Region |
I've also seen the incorrect bulb in the brake lights/tailights do some amazingly weird things. so true that also happen to me. (IMG:style_emoticons/default/agree.gif) On of my techs did this to a customer vehicle once. It was so simple 6 guys in the shop couldn't figure it out. The customer came in with the suggestion... fixed! (IMG:style_emoticons/default/confused24.gif) sorry. |
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