I just rebuilt it and had it running and doing fine tuning on it. It a '94' 3ltr V6 by the way. So today I was gonna like it run alot longer than I usually do to fully seat the rings. It starts up and runs fine for a 1 or 2 minutes then it sputters and shut off. I start it back up and a sputters and shuts off. If I wait 5 mins and leave the fuel pump on it'll start up run 1-2 mins and do the same thing. I changed fuel pumps and fuel filters and it does the same thing. What am I doing wrong you guys?
Found out my problem. I'm getting too much fuel. I just installed my O2 sensor and it did the same thing. Pulled my brand new platinum spark plugs and they were caked up with carbon build up. 4 of them were still saturated when I pulled them off a 3rd time. Is there anyway to do a injector cleaning without pulling the intake off?
Last edited by flipfloptrep; 02-06-2013 at 11:17 PM.
I rebuilt my 3.0 v6. I fired it up 8 months ago and I been dealing with this same issue. It runs good for 10-15 minutes then starts idling rough. If I kill it and try to crank it back up it sputters and dies. Sometimes it runs for 10 minutes and the oil light comes on and it starts to putt putt and it dies. I replace the ignition system accept for the distributor itself. I'm thinking my oil is too thin since I did get the cylinders lightly bored because of a scuff on #5 cylinder. The guy that honed it for my said I can just go with the stock piston rings. I'm using Pennzoil 5w30 right now and I thinking bout changing it out to a thinker oil like 10w30 or even 20w50 because the oil on my dipstick is very thin almost like water. I hope this will fix my problem cause other than this I don't know what to do. Any suggestions?
yeah, change the oil. you probably have heavy fuel dilution. if it's just rebuilt, stay with 5/30 til it breaks in more. no need for anything heavier than 10/30.
does it rev up at all?
have you checked the map sensor? unplugged it to see if it makes a difference?
Right now I have problems reving it up. It use to rev up alil bit then I advance the timing and it was revving up alot better. Now it want start where I had that timing set so I retard the timing and it idles very smooth but when I give it alil throttle it slows down but eventually revs up. I might need to post a video of that too. Haven't checked the MAP sensor yet.
well, the other thing you need to do is get a timing light and set it properly for the initial timing. else your just chasing problems from one direction to the next.
So I got my friend to help me with my problem and timing light. Hooked it up and found out I was 45-50 degrees after top dead center. I took the rotor cap off the distributer and everything was still allighned correctly. So I put back on the rotor cap back on and switch the wires around to fire a cylinder earlier and now she runs like NASCAR engine. Throttle response is the best I ever heard from one of these engines. Rotor buttom is lined up but according to the timing light and engine I'm off by one gear tooth. A head scratching moment.