Engine Performance problem
1977 MG Midget 4 cyl Two Wheel Drive Manual 38000 miles
car starts, runs, idles but acts like it's out of gas under load on the highway or going uphill. When it cools or you go down hill no load it runs again. I replaced fuel pump and lines, same thing, went to electric pump, same thing. Is there a in tank strainer? Could it be something in carb or maybe a heat sensitive electric problem? It seems to act up on a grade or heavy acceleration. Then goes back to normal until it does it again. Seems not to do it when engine is cool. Help please. Jim
Hi 64zbird, Welcome to 2carpros and TY for the donation.
Check and test the plugs/wires/coil if okay-check the fuel pressure to rule out the fuel filter/fuel strainer and the new fuel pump, also check the exhaust system for restriction, if everything so far checks out-check the transfer/metering/power valve circuits on the carbuerator
September, 1, 2010 AT 2:20 AM
My original problem has taken a backseat. After I changed the fuel pump and lines it now idles rough and it seems to have a vacuum problem. If I unplug the line to the canister it runs better but still misses off idle. The mixture screw makes no differance and is almost all the way out. Did I get some dirt in carb?If I rebiuld the carb do I need a new metering rod? Could the charcoal can be clogged? And can you bypass all that recirculation to the gas tank stuff? Is that little electric Ign module that is wired to the distributor suspect and can it be tested. You said to check the carb metering/secondary something on the carb. How do I go about that? Any help is much apreciated. Thanks
September, 1, 2010 AT 3:47 PM
Not quite familiar with this vehicle remember it back in the early 70's.
Check the fuel pump pressure if its within specs also is the ignition system has contact points if so check the dwell angle/gap and retime the ignition also test the coil primary and secondary windings.