02 Burb - Replaced motor...won't start?

[George C]

vats shouldnt do anything if its a replacement motor in the same vehicle


that isnt the crank sensor in back of intake its teh cam sensor and if you messed this up it wont run right. it would also throw a code asap if a wire is wrong somehting along the lines of high Freq

[Mr.Cornelius]

Hey guys im having the EXACT problem with the same issues can anyone PLEASE Help..

[truckinL33]

I don't know exactly what you did during the swap, but I would put the cam sensor from your buddies old engine into the new one and see what happens. The way you describe that cylinder 1 is soaked but the rest are dry, this may be because the cam sensor is damaged or something. It's free to do, and relatively easy. Furthure more, that exhaust bolt that broke off is common. It also happens to be on cylinder number 1 that it happens to. This is why I am assuming that cylinder number 1 is your fat cylinder, which is also why I am considering your cam sensor to possibly be faulty.

[oleshifty]

02 also had option of normal or flex fuel. It is possible the injectors on the NEW motor are a different size then his old motor. I would assume this would still start, but run pig rich, but it's hard to tell. I THINK the flex fuel injectors have a different plug, so it may not be possible to hook up wrong ones. Obviously make sure the coil packs are hooked up correctly on both sides. All injectors are plugged in, etc.

I would think a cam/crank sensor would throw a code immediately, but if you have spare parts laying around, won't hurt to throw them in and see if anything changes. They are just magnets. If motor sat a while, might be tarnished up and not reading correctly.

[Mr.Cornelius]

Thanks guys for the suggestions, Im going to try everything tonight. Would a cracked oring in the fuell supply or return line cause it not to fuel? It runs perfect when i spray fuel into the throttle body. IDK what to do I need my truck

[oleshifty]

If you have fuel at the schrader valve on the rail, it's probably hooked up right.


Double check the main injector harness, and make sure each one is plugged in all the way. If it 'runs perfect when you spray fuel in the tb, it's not a timing issue. It's a plastic intake that is only supposed to carry air, I'd be careful with that, good way to backfire and blow intake off. I'm assuming you have intake off, have you tried running it with the maf and everything hooked up? My truck doesn't run with the intake tube off the TB and nothing is wrong with it

[Mr.Cornelius]

I have, And I double checked the fuel injectors to make sure they were in, they seemed to click in alright. I suspect the fuel lines as the upper larger one (Supply??) was hard to get clipped when it did I was applying steady pressure and it snaped on. it seems like it tries to start every 2 revolutions on one or maybe two cylinders. Thanks for everything Guys, keep it comin

[Mr.Cornelius]

also thinking, maybe a crimped fuel line? I tried to make sure I didnt crimp em but hey, Im human and I make mistakes.