QuestionQUESTION: 1996 discovery V8 I replaced fuel pump ran fine for 2 days now just turns over won't start. Previously to that it ran a bit rough and if you turned it off and 5 minutes later it would start 10 minutes later it would not. you would have to let it sit for about 20 to 30 minutes before it would start. i get P1316 code which means bad spark but I get no kick at all when trying to start. Thanks for your time.
ANSWER: Hi Gary,
Have you verified if you are getting enough spark? How are the wires and plugs anyway - could there be a problem here? Do you smell fuel or are the plugs wet after several failed attempts to start?
How is the fuel pressure since you replaced the pump?
Crankshaft position sensor has been known to cause this problem too.
Best of luck,
JohnMc
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QUESTION: IS CRANK SHAFT SENSOR ANOTHER NAME FOR THROTTLE POSITION SENSOR
ANSWER: Hi Gary,
no, they are not the same device = although they both provide data needed by the engine management system. TPS measure your attempts to increase engine speed via gas pedal.
IF TPS was at fault - rev's would be rough, stalling, bad idle.
CKP fault could lead to bad ignition timing...hmmmm...
Best of luck,
JohnMc
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QUESTION: I KNOW WHAT TO LOOK FOR AS FAR AS PLUGS GO BUT WHAT DO YOU LOOK FOR WITH THE WIRES ALSO WOULDN'T YOU GET SOME FIRE i CAN'T SEE ALL THE PLUGS BEING BAD WOULDN'T MOST LIKELY BE SOMETHING THAT CONTROLS THE FIRING(JUST A GUESS) THAT SHOULD BE MY LAST QUESTION IT'S NOW A PROCESS AND THANK YOU SO MUCH FOR YOUR TIME!!!!!!!
AnswerHi Gary,
actually, if its a CKP failure, ALL the ignition timing would be off. IF the coil is at fault, again ALL ignition would be affected. You have to verify that you have spark - it may not be firing at the right moment though.
I think if you go to Advance auto - they may test your spark for you (free) if you ask politely. :) I know they'll test your battery and alternator for free too (just to be on the safe side).
In the 'old' days, you could remove a plug, attach the wire and hold it just above a ground point (or the engine block) and turn the engine over. IF you saw a spark, you knew this was working (sort of). But nowadays - this is frowned upon and you really have to know what you are doing. Best to have a timing gun and analyze the spark as it passes thru the wire.
You should take a closer look at the basics: starter, solenoid, main battery lead, coil, CKP, fuel pump, fuel pump relay (do you hear a click when you insert key and turn ignition 'on'?).
Best of luck,
JohnMc
