HT4100 4.1, 4.5, 4.9 Discussion, Car is running rich in Cadillac Engine Technical Discussion; Hey all if anyone has any ideas or suggestions it is all appreciated. My '85 Fleetwood Brougham sporting the famous ...
Hey all if anyone has any ideas or suggestions it is all appreciated. My '85 Fleetwood Brougham sporting the famous 4.1 is running rich. I had the car tuned up at the dealer about a month and 1/2 ago, and they changed the spark plugs, fuel filter, and should have adjusted the timing. But I did notice like 2 or 3 weeks ago that the car is running rich, I can smell it when I walk around the car while it is running. Any help is appreciated, thanks.
Automobile(s): 1988 Allante' (sold), 1984 Eldorado, 84 Sedan DeVille
Re: Car is running rich
If in fact its running richer than spec, the service eng soon or service engine now light would be on. If neither is on, the engine is operating within spec. Advise if either light is on? Advise if any codes are present.
You could take the aircleaner off and watch the injectors while you turn the key on to energize the fuel pump....without cranking the injectors shouldn't drip or inject any fuel. You can see them clearly in the pods above the throttle bore so if they are leaking or dripping it would be obvious.
One way to do a rough check on whether the injectors are controlling correctly is to compare the fuel used on the data center to the actual fuel used at the pump. Reset the data at the next fill and track the electronic data compared to the pump data at the next fill. They should agree pretty closely. If the actual fuel put in is greater than the electronic data on the dash then it is an idication that some fuel is going into the engine that is not metered by the system...i.e...leaking injector, fuel pressure off, etc....
How is the fuel economy. If it is about the same as usual then I wouldn't expect it to be running too rich.
I do compare numbers between the car's fuel data center and the fuel pump and they are very close. According to the car's fuel data center I am getting an average of 14 - 16 MPG of combined driving (more city than high way).