Rebuilt engine, won't start.
Thread Starter
Staging Lane
Joined: Nov 2008
Posts: 50
Likes: 0
From: Sanford,ME
Rebuilt engine, won't start. I just reinstalled the engine in my 96, it turns over but won't start. It has spark to the plugs, has 43 lbs. fuel pressure. I took a lot of care to make sure I reinstalled the opti correctly. When it's turning over it will backfire from the exhaust and the intake which seems like a timing problem. Plug wires are all in the correct order. I haven't touched the opti. It ran good before, I just took it off and put it back on. Any ideas ? I'm hoping I'm missing something simple.
Teching In
Joined: Nov 2013
Posts: 34
Likes: 0
From: N. Berwick, Maine
What if the water pump is out of the car and the ECT sensor is not connected? Would this would cause the PCM to read -40 for coolant temp by an open circuit correct? If thats the case then it would be dumping too much fuel and preventing the engine from firing?
TECH Veteran
Joined: Apr 2008
Posts: 4,985
Likes: 112
it is possible you didn't get the cam dowel in the right Opti position.
Did the opti push on easily and was it completely flush with the block before you put the 3 bolts that hold it on?
backfire at random does often mean a opti issue not being positioned right
with that said incorrect valve lash also as noted
Did the opti push on easily and was it completely flush with the block before you put the 3 bolts that hold it on?
backfire at random does often mean a opti issue not being positioned right
with that said incorrect valve lash also as noted
Teching In
Joined: Nov 2013
Posts: 34
Likes: 0
From: N. Berwick, Maine
it is possible you didn't get the cam dowel in the right Opti position.
Did the opti push on easily and was it completely flush with the block before you put the 3 bolts that hold it on?
backfire at random does often mean a opti issue not being positioned right
with that said incorrect valve lash also as noted
Did the opti push on easily and was it completely flush with the block before you put the 3 bolts that hold it on?
backfire at random does often mean a opti issue not being positioned right
with that said incorrect valve lash also as noted
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TECH Addict
Joined: Dec 2010
Posts: 2,610
Likes: 4
From: Maricopa, AZ
Did you do any mods while you were rebuilding it? Did you adjust the tune for the mods? It still shouldn't backfire though.
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Verdad Gallardo Teching In
Joined: Nov 2013
Posts: 34
Likes: 0
From: N. Berwick, Maine
During the install we replaced the stock cam with the Lt4 hotcam. We have a reprogrammed computer but havent yet installed it, we figured we could atleast verify that the engine runs. It ran on the old computer fine so we figured it would atleast fire on the old one.