power surge light load | 356 Speedster, 550 Spyder, Replica, Automotive Community

Former Member

I am getting a strange power surge under light load and when my car is hot only. under light throttle the engine will rev up and if I lift off the accelerator it will continue to rev. I first thought it was the notorious Dellorto drip...but it doesn't seem like they are dripping and I am not getting any barks through the carbs or exhaust. I checked my linkages and they seem ok. This problem started after I pulled the engine last summer to do a couple of things and had the carbs off. Just sitting in the driveway and reving it from the linkage it behaves just fine...just under light load while driving. I did adjust the valves and wondering if perhaps this is an ignition advance issue.
any thoughts?

Paul
1986 envemo cabrio

3/18/1210:08 AM

Original Post

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Former Member

I am getting a strange power surge under light load and when my car is hot only. under light throttle the engine will rev up and if I lift off the accelerator it will continue to rev. I first thought it was the notorious Dellorto drip...but it doesn't seem like they are dripping and I am not getting any barks through the carbs or exhaust. I checked my linkages and they seem ok. This problem started after I pulled the engine last summer to do a couple of things and had the carbs off. Just sitting in the driveway and reving it from the linkage it behaves just fine...just under light load while driving. I did adjust the valves and wondering if perhaps this is an ignition advance issue.
any thoughts?

Paul
1986 envemo cabrio

3/18/1210:08 AM

Former Member

Try loosening the throttle cable a bit. You may have a torque issue that causing the cable to pull open the throttles. If that's the problem then check horns (2 protruding metal tubes that hold the transaxle and, check motor and transaxle mounts.)

3/18/1211:44 AM

Former Member

I think you might be on to something with the accelerator cable. I did replace it when I pulled the engine...its possible it could be binding when hot. I'm gonna check that out. thanks.

edsnovaBaltimore - BCW 52 MG TD Supporting Member

look for a vacuum leak while you're at it.

Gremlinx

Mine did this and it turns out my throttle shaft bushings are worn, causing my vacuum leaks.

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