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Fri Aug 15, 2008 8:07 am

'68 fuel injection, manual trans

Lately, my square has been having some runnability issues when warmed up. When it is cold, it runs like a top, but when it is hot, it sputters real bad at high rpm's, and on acceleration. I can tell that it's about to run poor, because when I turn left, it starts to go to hell.

I found that broken/ loose wires on the MAP, and that my coil was reversed(+ to 1, condenser to 15). Fixing that did not help. I replaced the coil, thinking that it might have been damaged, but that didn't help. Could the condenser be whacked?

This is my daily driver, 65 mile round trip commute on the freeway. It happens day, or night.

Fri Aug 15, 2008 8:16 am

I would check all the air hoses for leaks first. Air leaks make it run rich, which is needed when it's cold, explaining why it may run fine then but not when warmed up. Next I'd check the fuel pressure, and then the MPS for a leaky diaphragm. Also check that your AAR closes (at least, mostly closes) when warmed up. These are free checks and often catch the problem.

Fri Aug 15, 2008 8:27 am

Thanks for being so quick.

Fuel pressure is set at 30 psi, I cannot find any vacuum leaks, MPS does not leak, and my AAR is disabled (pinched closed between AAR and intake.)

The sputter seems to be either loosing spark, or fuel, as it does not seem to be detonating, although it may be due to the fact that it is only doing this when hot. Worse with left turns then when going straight or turning right.

The clock is also still slow, but I don't think that is related.

Fri Aug 15, 2008 8:58 am

Is the ashtray full? What color is the car?

Sorry, channeling Click'n'Clack...

Worse when turning? Hmmm, that's strange. I'd guess fuel tank related maybe? How is the sock/filter looking?

Ground wires tight on the engine?

Gen voltage okay?

Next I'd do the "wire wiggle" to see if a loose connection is breaking when cornering and the engine tilts on the mounts.

Tue Aug 19, 2008 8:44 pm

I may have found my issue.

The JB Weld that was holding my distributor clamp stud into the case had finally given up. After tapping the hole bigger, and installing a stud-like object, the car seems much better. Maybe the torquing of the engine with a loose distributor was causing a timing change enough to cause a miss?

Of course, TheSamba gurus didn't tell me to check the JB Welded stud, I had to find that one on my own!!

Tue Aug 19, 2008 10:28 pm

rosevillain wrote: I may have found my issue.

The JB Weld that was holding my distributor clamp stud into the case had finally given up. After tapping the hole bigger, and installing a stud-like object, the car seems much better. Maybe the torquing of the engine with a loose distributor was causing a timing change enough to cause a miss?

Of course, TheSamba gurus didn't tell me to check the JB Welded stud, I had to find that one on my own!!

It may also have been a grounding issue. Once, years ago, I forgot to attach the condenser to the distributor on a customer's Beetle. It acted exactly like that. :oops: