running rich

[bob h]

Hi all, My 93 D1 auto runs fine except when cold. When cold/warming, and under acceleration up to 3000rpm, it blows lots of black smoke. Also blows some [a lot less] when hot. Have adjusted the TPS and MAF to the settings as reccomended on here and it runs a lot better. Is there a cold start injector that could be playing up or is it the ECU sending the wrong signals under acceleration. Proberbly not as I think a sender of some sort/somewhere could be giving the wrong readings. Any ideas/help very much appreciated. Oops, forgot to mention that the adjustment screw on the rear of the nose of the phlenumn [idle adj, I think] is adjusted all the way in [as in turning the screw to the right looking from the front of the motor]. If adjusted out the motor increases in idle speed. Now idles at approx 800rpm. Thanks, Bob

[Pedro_The_Swift]

sounds like its running full rich,,,

[bob h]

sounds like its running full rich,,,

Still getting approx600ks on a trip though and 450 490ks around town. Just blows black smoke under accel with accelerator only 1/2 way down to the floor. Bob

[pibby]

there are two coolant temp sensors - one for the dash gauge and one for the ecu. this latter one might be playing up so the ecu doesn't know that the engine is up to temp so keeps feeding a rich mixture.

have attached a pdf which has the resistance readings of the ecu coolant temp sensor so you get an idea of what it is doing. however, for the sake of $25 or so go get a new one then you can definitely cross it off as working properly.

http://www.aulro.com/afvb/attachments/electronic-diagnostics/25965d1275822804-temperature-switch-controls-ecu-running-resistance-14cux_fuel_injection.pdf.pdf.pdf

also, there is also a fuel temp sensor however i believe this to be more related to hot starting so probably not part of your problem.

[cockie55]

Still getting approx600ks on a trip though and 450 490ks around town. Just blows black smoke under accel with accelerator only 1/2 way down to the floor. Bob

If that is your true fuel consumption out of of a 20 yo RV8 then I think you have a major valve cook / lean out problem.