I spent a few minutes last night testing each spark plug with my trusty induction strobe light. I zip-tied the trigger down, laid it on the engine and pointed it at the drivers seat. I started the car for the first 2 plug wires; both flashed nice and bright until the engine died. Then I tried to see if I could get the engine to run longer than 10 seconds at a time so I could work a bit faster. Surprisingly enough, I did get it to idle with the gas pedal about = down I used the throttle handle to keep it running as I rummaged about in the engine compartment. I tested the remaining two plug wires and they flashed as prettily as the other two. No help here.
While staring at that lumpish engine, I decided that maybe I should retrace my diagnostic steps from the beginning since it was running longer than 10 seconds at a time.. My eyes focused on the SPICA pump and my hand reached for the wire on the cold start solenoid (CCS) pulling it off which made no difference - put it back on. Pulled the wire off the fuel cut-off solenoid (FC-OS) it immediately perked up and sounded right ! What !!?? Huh ??? WTF ??? I pulled it on/off several times to make sure I wasnt hearing things but yes, the FC-OS was the culprit! Now the FC-OS was being powered by the always-on micro-switch. And instead of killing the engine, it was only doing half a**ed job. The CCS would feed enough gas to get the engine started but as it reduced the flow, the FC-OS wouldnt allow enough to keep it running without some serious gas pedal input. But I thought that I had tested these two wires way at the beginning of this frustrating episode but thinking back on it, I really hadnt.I just assumed a few things. When the symptoms first appeared I was on the street heading to work. The first thing I did was open the hood, removed the fresh air tube from the air cleaner and reach in to pull off the CSSs wire and restart the car. Then I went back and put that wire back on the CCS which was when I found the FC-OS wire loose already loose. My instant reasoning when like this: MMmmm, removed CCS wire and FC-OS wire already removed then both did not affect the operation. FC-OS wire was never attached therefore it never affected the operationrule them both out. I had previously removed the FC-OS wire since I was getting a wee bit o backfiring on deceleration and I was testing things out. Then to make matters all that much worse I put the FC-OS wire back on thinking that it didnt matter. Now I believe that the FC-OS wire was barely touching the terminal on the FC-OS and making it misbehave. But Ive no idea if the SPICA micro switch failed on its own or did the loose FC-OS wire short out at some time and that fried the switch. Ill be testing the FC-OS wire for voltage; maybe a low voltage wasnt enough to fully power the solenoid but enough to make it be half on. Then Ill jumper the FC-OS from the battery to see if it is still useable. Ill leave the micro switch alone until I pull the SPICA in the future. There were two good things that came out of this: I found that Im not getting a full 12v at the coil which needs to traced down, and I went and changed the front fuel filter which is a real PITA to do so I have been putting it off. Thanks for all the suggestions as to where to look for the cause. Here's one instance where an electrical problem caused a fuel problem! Bruce '73 GTV On Fri, Sep 30, 2011 at 9:54 AM, Bruce Giller <[email protected]> wrote: > My '73 GTV suddenly developed a problem on the way to the track today (so > much for any fun this weekend). It started up fine and idled easily in the > driveway - like it always does. But just 100 yards down the road it died as > I was shifting. After that I could get it to start and it would run and > then the rpms would just slowly drops until dead. If I held the throttle > down a bit it might stay running a bit longer but not by much. I started it > about 20 times with the same results - the engine ran strong (read normal > sounding) after catching and then fall off. I was able to get it back to > the house by holding the throttle almost to the floor (no power at all to go > up even a modest incline) and re-starting it when it died. Needless to say > I had some very choice words to say to it.... > > It sounds very much like a gasoline supply problem but the low pressure > fuel light which is on before turning the key, was off quickly after hearing > the fuel pump running - the fuel pump was running all the time. My current > suspect is water in the gas but I thought that water would prevent it from > starting easily which isn't the case. And it drove nicely yesterday > afternoon on the same tank of gas. > > Any ideas where I should investigate? If I can get it fixed by Sat. I can > drive up to Summit Point on Sunday to get at least one day of track time > this year. > > Bruce -- to be removed from alfa, see http://www.digest.net/bin/digest-subs.cgi or email "unsubscribe alfa" to [email protected]
