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4.3 won't start

21K views 9 replies 3 participants last post by  morganl0592 
#1 ·
2005 4.3 150,000 miles won't start. Timing is ok,fuel pressure well above 50 lbs, getting fire, I can smell gas from throttle body and also from the exhaust (after cranking a few minutes). Every 5-6 revolutions it will shoot air from the throttle body sometimes with flame like a backfire that's why I thought it was timing but I pulled the distributor and it all looked good and hooked up a timing light and the timing checked out ok. I'm at a standstill now any advice is appreciated.
 
#7 ·
morganl0592 said:
I replaced the intake plenum gasket. I tried spraying carb cleaner into throttle body while cranking. Neither one helped. All spark plugs are firing but it's more of a white spark. Is it supposed to be blue?
Spark should be blue.
Do more testing. Do not throw parts at it. Your crank sensor is fine. You would have no spark at all if there was a problem with it.
Cam sensor is for injector timing and WILL not cause a no start issue.

You may have got the distributor in the wrong spot when you re installed it. A very common problem when doing an intake gasket.
Set the #1 cylinder at TDC on the compression stroke and check to see if the distributor rotor is pointing at the #6 cast into the distributor base
 
#9 ·
Pull the cap off the distributor and spray it with WD40. WD40 is a water displacement.
On these engines its best to use AC Delco cap and rotor and coat all the contacts inside and out with dielectric grease. It prevents moisture and corrosion on the cap.
Also check to see if the distributor vent is clear.
 
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