Folks, I'm a bit stumped.
Background: my 1990 325iS has about 117kmi on it and as of now is 101% stock (minus some cosmetic interior stuff). Last summer, due to scoring in the camshaft journals, the head was replaced. Since then, every single rubber hose/gasket in the engine bay has been replaced, the injectors + manifold were cleaned, the air meter was recalibrated, etc. I will not go into the details of how much money was spent (I can't do most of the stuff myself, having very limited time) but suffice it to say that I have literally run out of options on what to replace.
The mechanic helping me in the endeavour is held in very high regard in the local CCA chapter and is generally considered the 'go to' person for E30s.
After all this work, the engine still has three problems:
1) with the AC disconnected, it idles around 600-650 rpm, therefore it's rough at idle. The ICV has not been replaced because mr. mechanic maintains that this is correct idling behaviour. I maintain that it is not. Ideas?
2) The car has developed a lovely warm-start issue, wherein to start it when warm you have to have the gas pedal slightly pressed, otherwise you have to crank it for literally 40-45 seconds. This results in a significant unburned gas smell, something a car with a cat should never have.
3) Gas mileage is positively horrid: I get 18-19 MPG on a regular basis, managing to get to 23-24 when I do highway only, below 80mph. The result of a recent trip up to NYC where 80 mph was somewhat exceeded compares unfavourably with the 996 turbo in europe - at twice the speed.
CO levels were measured and they were sort of OK - not as good as I expected them, CO2 was a little low and CO was not at 0, plus Lambda was not at 1.00.
I am starting to suspect 1) the air-fuel meter 2) the ICV 3) one or more injectors. Any help will be appreciated.
Background: my 1990 325iS has about 117kmi on it and as of now is 101% stock (minus some cosmetic interior stuff). Last summer, due to scoring in the camshaft journals, the head was replaced. Since then, every single rubber hose/gasket in the engine bay has been replaced, the injectors + manifold were cleaned, the air meter was recalibrated, etc. I will not go into the details of how much money was spent (I can't do most of the stuff myself, having very limited time) but suffice it to say that I have literally run out of options on what to replace.
The mechanic helping me in the endeavour is held in very high regard in the local CCA chapter and is generally considered the 'go to' person for E30s.
After all this work, the engine still has three problems:
1) with the AC disconnected, it idles around 600-650 rpm, therefore it's rough at idle. The ICV has not been replaced because mr. mechanic maintains that this is correct idling behaviour. I maintain that it is not. Ideas?
2) The car has developed a lovely warm-start issue, wherein to start it when warm you have to have the gas pedal slightly pressed, otherwise you have to crank it for literally 40-45 seconds. This results in a significant unburned gas smell, something a car with a cat should never have.
3) Gas mileage is positively horrid: I get 18-19 MPG on a regular basis, managing to get to 23-24 when I do highway only, below 80mph. The result of a recent trip up to NYC where 80 mph was somewhat exceeded compares unfavourably with the 996 turbo in europe - at twice the speed.
CO levels were measured and they were sort of OK - not as good as I expected them, CO2 was a little low and CO was not at 0, plus Lambda was not at 1.00.
I am starting to suspect 1) the air-fuel meter 2) the ICV 3) one or more injectors. Any help will be appreciated.
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