Ah yes, "Smoking can be hazardous to your health"! For the mighty Herc, not so much... but as Catmando (& his Avatar will attest), in No. Vietnam it was a AAA gunner's delight around the target. F-4 Phantoms (J-79), and A-4E (J-52) models were the problem "smokers"….It was estimated that on a clear day, the F-4s/A-4Es could be visually acquired by AAA gunners at 15+ miles, compared to 5-7 miles for A-4Cs.
Smoke-abatement systems were designed for both offending type/model engines, but the A-4s were just about phased out by A-7s before they could be installed. I don't know if the F-4s ever were retrofitted before the air war ended.