1998 Silverado P1345, P0340, P03-than-expected cutting out in cold/damp conditions after timing issues and distributor replacement
I replaced the intake gasket one year ago and initially resolved a timing issue after several attempts—seemed to run fine at first. However, six months later, the engine would fail to start after being left for a month, acting as if it were out of time. I replaced the crankshaft position sensor and re-adjusted the distributor, which allowed it to start again. After another six months, I began experiencing intermittent stalling—especially in damp or cold weather. The vehicle now runs erratically even when warm. Recently, I've been getting diagnostic trouble codes P1345 upon startup, followed by P0340 and P0341. While it may run briefly, the symptoms are inconsistent and severe. I have already replaced both the fuel filter and fuel pump with no improvement. I live in Florida where temperature fluctuations are common. The issue appears to be more pronounced during cooler or humid conditions. There is no backfiring—only sudden cutting out, similar to a fuel starvation condition. Given these symptoms and recurring codes, I'm seeking advice on potential root causes and solutions for this 1998 Silverado with persistent ignition and timing-related issues.
The most likely solution is replacing the entire distributor with a high-quality unit. Distributors in older vehicles like the 1998 Silverado are prone to floppy shafts due to worn bearings and damaged gear teeth, as well as degraded electrical components under the cap. While timing can be adjusted using a scan tool for precise alignment, it's highly unusual for a distributor with these issues to generate P0340 or P0341 codes—these typically point to sensor or ignition system faults. A new distributor should resolve both the stalling and code generation problems. Good luck, and please update us on your progress!