TPS testing question?, Car is bucking under load |
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TPS testing question?, Car is bucking under load |
Jon H. |
May 25 2016, 10:26 AM
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#1
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Member Group: Members Posts: 237 Joined: 1-July 11 From: Ottawa, Canada Member No.: 13,264 Region Association: Canada |
Hello, I had my 73 2.0l out for its maiden voyage this year and the car was running great. On the way home I stopped at a light and when I took off the car was bucking horribly. I investigated and found the bolt under the plenum that grounds the wires for the TPS and, I think, the injectors had come out. I re-installed it checked the grounds, checked continuity between the ecu and the TPS and all is good. I checked the continuity of the TPS as the throttle is opened and closed and it appears that there are about three position that are open circuit. They are small gaps though, barely having to move the throttle to get continuity again. It this normal? Should there be 'flat' spots as I move the throttle or should there be 100% continuity all the time? I did remove the TPS and have a look and it looks fine. Could an arcing ground have caused the TPS to fail?
Thanks in advance! Jon h. |
rmital |
May 25 2016, 10:57 AM
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#2
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Northeast optimist Group: Members Posts: 1,947 Joined: 12-December 05 From: Park Ridge, NJ Member No.: 5,268 |
...check the connection from the harness to the CHT (cylinder head temperature sensor).
bad sensor or connection could cause bucking. or at what RPMs are you getting the bucking? consistent at certain RPMs....or thru all ranges? |
Jon H. |
May 25 2016, 11:09 AM
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#3
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Member Group: Members Posts: 237 Joined: 1-July 11 From: Ottawa, Canada Member No.: 13,264 Region Association: Canada |
...check the connection from the harness to the CHT (cylinder head temperature sensor). bad sensor or connection could cause bucking. or at what RPMs are you getting the bucking? consistent at certain RPMs....or thru all ranges? The bucking is while at cruising speed, 1800 or so, if my tac is accurate. I still have power off the line. I'll check the cht tonight. Thanks. Jon h |
rmital |
May 25 2016, 11:40 AM
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#4
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Northeast optimist Group: Members Posts: 1,947 Joined: 12-December 05 From: Park Ridge, NJ Member No.: 5,268 |
...check the connection from the harness to the CHT (cylinder head temperature sensor). bad sensor or connection could cause bucking. or at what RPMs are you getting the bucking? consistent at certain RPMs....or thru all ranges? The bucking is while at cruising speed, 1800 or so, if my tac is accurate. I still have power off the line. I'll check the cht tonight. Thanks. Jon h if cruising then probably not CHT. if off the line it's all jerky, then it could have been... |
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