HT4100 4.1, 4.5, 4.9 Discussion, 4.1 Sputters and pops in Cadillac Engine Technical Discussion; My 1985 FWB with the 4.1 Ht4100 sputters and pops, especially under exceleration. As I have said before, I know ...
The sputtering/popping will happen any time I accelerate, weather I just started her up or I have been driving for a while. It seems to be especially bad if im in 3rd or fourth gear and start to accelrate.
Well I dont think it would be the cam, because it just all of a sudden started happening one day. I would be more suspicouise of the fuel system except it feels like it happening in only one of the cylinders. It feels like one of the cylinders on the driver side just isnt fireing wright.
She needs a tune up any ways so Im gonna go ahead and replace the rotor, cap, incap-resistor, wires and plugs.
Does any one knoe if this is an HEI setup?
I had the exact same problem on my 85 FWD fleetwood trned out to be a cupped lifter in #7 cylinder (cam ate lifter), i wasted my time and money witht he whoel igniton system, fuel press was fine. And yes mine happened out of the blue. I replaced the lfiters, ran good, btu i never checked pick up tube wether it was clogged or not, and my bearings discintigrated. Replaced motor and sold the car. car had 99,000 MILES on it, 159,000 KM's.
Automobile(s): 1988 Allante' (sold), 1984 Eldorado, 84 Sedan DeVille
Re: 4.1 Sputters and pops
Yes this is an HEI. With no codes related, start with plug wires and plugs. Make sure all wires are routed correctly by the book. If routed incorrectly this engine will cross fire causing a miss. You only have 2 injectors on this engine so an injector is unlikely. If after the wires and plugs it still pops, then pull the valve covers to verify all rockers are fully pushing open the valves. Popping thru the intake on hard throttle is a sign of a flat cam or collasped lifter.