I had an '80 Riv that took to full-on blowing at 3 in the mornings one Fall when the weather turned crisper. It took a while [before internet] to find it was common issue from contracting bi-metal contact sheets in the cold combined with the thin perforated foam separating them that decayed and shrank to nothing over time.
I can't believe it if they might have kept that same chintzy design 15 years later. I have to admit I've never heard that problem with our cars though since joining the forum.
\'96SS SOB: SSRI, Herter Tune, Tri-Y II, , 3000 Edge, F/HO bars, METCO extendeds with CV MMC, Bilsteins, currently Vredestein Ultrac Sessanta (315/35 rear). Finally, wait for it... LT-4 knock module!
\'96FWB BUW-Butt Ugly White: PCMPerformance tune, HDFA w/ swissed filter, 1/2 SLP s.s. catback with H- and Flow Super 50s, oem opti rebuilt 3 times, SS Bars, METCO LCA, Airlift 1000, Monroe SS, PowerTrax No-Slip, CTS wheels with +1 rubber. Finally, yes again... LT-4 knock module!