408 wont start
408 wont start Just got the new iron 408 in my 98 WS6 and Im getting the p0335 code and a crank no start. Tried the 6.0s crank sensor, and it will try to hit and will run a second or two and shut off. New sensor (from advance) wont even try to start. Checked all the grounds, checked the harness and all is good. I checked the reluctor wheel before it went to the machine shop and it was positioned right with the right teeth. Turned the motor over by hand and watched the wheel thru the hole and no damage.
My next move is to get a gm sensor and try that but does anybody else have any ideas? Thanks alot
My next move is to get a gm sensor and try that but does anybody else have any ideas? Thanks alot
98 pcm and a 24 tooth wheel. The car had a 346 with a tsunami cam and heads and a fast intake, so the tune is for that and id think it would atleast start since the injectors and mass air sensor wasnt changed.
Not to overload you with the ground recommendation, but I just spent two weeks trying to figure out my issues on a new 408 I just built. Turns out it was just a loose ground in the back of the head. So recheck all grounds and make sure they are tight.
I did check them, But I will do it again. All the sensors are hooked up for sure. Has anyone had bad luck using the same bolt for all 3 grounds on the back side of the head? Or do I need to split them up?
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Verdad Gallardo The odds of all those sensors you have tried being bad is slim to nothing. Hook up a scanner to the PCM and crank over the engine. While the scanner is showing real time data check the RPM and this will tell you if the PCM is seeing anything from crankshaft sensor. If it doesnt then you got an open or shorted to ground or even a crank sensor output hot to ground or positve. Any one of those types of faults will give you your symptom. You can disconnect the wire and put a fluke 87 on it and set it to VDC and you should get a peak of around 5vdc (this sensor puts out an dc square wave). Then there is the dreaded reluctor knocked off its proper spot on the crank. I would think it would atleast fire up but may not run much if that were the case.
Last edited by remauto1187; Aug 8, 2011 at 04:15 PM.
