1227730 speed density computer...Rich....
Thread Starter
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
1227730 speed density computer...Rich....
350 engine L98 cam, 1.6 rockers, duals, headers, engine rough as hell, and running rich on both banks.....anyone any clues?? been fighting this for several months now.....
New heated O2 sensor, temp sensor, etc....pressure is adjustable and don't seem to matter.....all the injectors are batch firing, and sound alike with a stethoscope.....plugs turn black from too much fuel....or really gross oil consumption??.......exhaust is not black though....but both pipes are rough as hell to the feel in back, and can see the exhaust is rich.....
Comp sets code 41 cyl select error.....whole bunch of black/wh wires going to engine ground......
New heated O2 sensor, temp sensor, etc....pressure is adjustable and don't seem to matter.....all the injectors are batch firing, and sound alike with a stethoscope.....plugs turn black from too much fuel....or really gross oil consumption??.......exhaust is not black though....but both pipes are rough as hell to the feel in back, and can see the exhaust is rich.....
Comp sets code 41 cyl select error.....whole bunch of black/wh wires going to engine ground......
Last edited by mrvette; Jan 6, 2022 at 05:46 PM.
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
Scanner? Vacuum leak(s) effecting MAP sensor reading usually causes rich situations with speed density. Rich conditions can cause restricted cat converter. Restricted cat converter can cause low vacuum and rich condition.
Since I think this is in a c3. Did it ever run correctly?
Since I think this is in a c3. Did it ever run correctly?
Burning Brakes
Joined: Aug 2006
Posts: 1,061
Likes: 99
From: Seattle WA
Good question on 'did it ever run right while you had it'? A lot of people swap cams to something more aggressive (which lowers vacuum -> to the ECM lower vacuum=engine under load=more fuel) without doing a tune. Even small cam swaps need a complete retune with speed density.
