New motor wont start!!
New motor wont start!! Ive been trying to start up my new 408 motor this past week and i cant seem to get anywhere with it. One problem is I cant get my fuel rails to stop leaking out of the fittings, but it is only a fast drip, not spraying. At one point i got it to hold and tried to start the car and it still wouldnt start. I would think that wouldnt be enough to stop the injectors from spraying. Now im starting to think that I may not be getting a spark or that my injectors got clogged up from the sealant i used on the fittings in the rails. I pulled a spark plug and it was dry. Is there anyway to test that im getting a spark and that my injectors are spraying? Could there be something electronically stopping me from starting it? When I pulled the motor the pins for the plug on the crank position sensor got ripped out. I had a friend
who is very good with electrical stuff re-pin the wires. If there is something wrong still with that sensor, could that be stopping the injectors and/or spark from working?
who is very good with electrical stuff re-pin the wires. If there is something wrong still with that sensor, could that be stopping the injectors and/or spark from working?
On The Tree
Joined: Jun 2007
Posts: 106
Likes: 0
From: kingsville, Tx
first things first I would try to fix the leaking injectors. next I would pull a plug ground it out and have a buddy turn the motor over. if its grounded right you can see it spark. just don't hold it in your bare hands it'll shock the **** out of you. you can also feel the injectors pulse as the motor is turning over. if those are both working, it should start.
I tested for spark and didnt get anything nor did the injectors fire. Im pretty sure my crank position sensor is not working right. those 2 things not working are the symptoms of a faulty crank sensor.
If i have a different reluctor wheel than stock could that also cause my crank sensor to not work?
If i have a different reluctor wheel than stock could that also cause my crank sensor to not work?
Ok fixed the fuel leak and crank position sensor. I got it to start twice but killed cause we thought something was wrong but it was fine. let it sit a little while tried to start it and it wont start now. at first it would fire a few times now im getting barely anything. I smell a little bit of gas when u prime it and i tested for spark and its working. Thought maybe the battery was charged enough cause the volt meter was low. charged up the battery and its reading fine now but still wont start. Fuses are ok. WTF???
Ok got it to start, now it wont idle. it will run for a couple seconds if you give it gas then it dies. My friend seems to think he heard an odd noise coming from the engine but i didnt hear anything odd. I think it was just my huge cam and open headers. Could something be internally wrong with the engine causing it to not idle? before any of this happened it would idle at 800.
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If your car is not tuned for bigger injectors then it will run for a second or two and die. At least have someone with hp tuners or another program put in the correct injector sizes. Your going to foul the plugs very quickly.
update: verified with tuner that the injectors were tuned correctly.
SES light was on and i scanned it with the following codes:
P0335-crank sensor(fixed)
P0405-EGR(removed)
P0443-EVAP Purge solenoid(removed)
P0803-skip shift
I dont think that any of these codes would be causing my problem. Next theory is that maybe my o2 sensors are reading wrong since im running open headers at the moment but I dont think that would be enough for it to keep it from running. I have an extra set of plugs that i may try and see if it works.
SES light was on and i scanned it with the following codes:
P0335-crank sensor(fixed)
P0405-EGR(removed)
P0443-EVAP Purge solenoid(removed)
P0803-skip shift
I dont think that any of these codes would be causing my problem. Next theory is that maybe my o2 sensors are reading wrong since im running open headers at the moment but I dont think that would be enough for it to keep it from running. I have an extra set of plugs that i may try and see if it works.
Ive got a 408 with a ported fast 90/90, 246/254 custom cam, TFS 235cc heads, open LT headers, air and EGR removed, 6 speed. It has professional products fuel rails with 42lb injectors. anything else?
Another thought, could a vacuum leak be causing this?
Another thought, could a vacuum leak be causing this?
Well i started it up again and earlier my friend was saying he heard a clunking noise and now i think i might hear it too. it is very hard to tell because its so loud with open headers. Im thinking that maybe a rocker arm could be loose or that a pushrod is not installed right? could this be causing my idle issues? I dont remember hearing this before when it was running right.
I pulled the passenger valve cover to investigate the weird noise and i found that a few of the pushrods werent sitting in the rocker cups. they were still touching just not fully seated or in the correct spot. fixed one of them and now that last one doesnt want to line up.
the rockers were not loose. one or 2 of the pushrods were just not sitting in the cup of the rocker. Now i got the one thats been giving me trouble to line up with the rocker cup. the the exhaust valve wont open now. Went it was running i noticed there was smoke coming out of the intake and at one point it started to blow off the lid. does this mean the lifter could be damaged or maybe the cam? something internal where i would have to pull the head off?
So i cant get any movement out of the pushrod on the #8 cylinder. the intake moves just fine but the exhaust is just dead. Im assuming the problem has to be with the lifter or cam. took out the pushrod and its fine. there was also a very very small scrape on the pushrod but not bent up or anything.
I have head studs, will it be possible to remove the head without pulling the motor?
I have head studs, will it be possible to remove the head without pulling the motor?
ok the #8 cylinder seems to be working fine. the piston second to last on the passenger side is the one acting up now. the exhaust valve on this one is not opening up. Ive rotated the motor a million times and it wont do anything. I also used the starter to turn the engine over(without spark or fuel) and I hear it crank and then it makes that banging sound once it gets to that certain cylinder. If you push on the other pusrods it will compress the lifter a little bit. this one does nothing. It just sits there while everything else is moving. I remember having this same problem with the #8 cylinder and all of the sudden it just decided to work.
This has to be a problem with either the lifter or cam. Any input is appreciated.
This has to be a problem with either the lifter or cam. Any input is appreciated.