My car ran fine before I took the front cover off to put on a double roller chain and sprockets. I ordered the sprockets and chain from CottonsPerformance. I lined up the dots on the old sprockets before removing, and put the new ones on immediately after removing the old ones, dots still lined up. I've used the voltmeter method to set the cam sensor, and the method of lining up the dots, but everytime I turn it over, is sputters like it wants to start but won't. I tried both methods of setting the cam sensor at least 15 times with the same results everytime. I put a new crank sensor on, same results. I tried a cam sensor from another engine that ran when parked, same results, but both cam sensor have been bumped around a bit in the process. I have verified that it has spark, and fuel, but apparently not at the right time. Could the timing sprockets be the wrong size? How sensitive are the cam sensors to rough handling? So close to starting but wont..... Please help
Almost starts but won't
- Thread starter dnthmn87
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turbojkt
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You might try setting the timing several degrees (not sure how many..5-10) ahead or behind to see if that makes a difference. Maybe someone else will post a suggestion on how many degrees ahead or behind you might try.
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Sure it's not 180* out? Turn the cam sensor till it runs.
180 out will still start, if you hear it catch but it wont stay running then it points to control system issues.
Have you tried cracking the throttle open a little when trying to start?
Do you know if you are getting fuel pressure?
unplug the MAF, see if it acts different.
check for harness wires pinched in the area of the front cover and AC bracket (since you had that stuff off).
What chip? What injectors?
Bob
Have you tried cracking the throttle open a little when trying to start?
Do you know if you are getting fuel pressure?
unplug the MAF, see if it acts different.
check for harness wires pinched in the area of the front cover and AC bracket (since you had that stuff off).
What chip? What injectors?
Bob
GNONYX
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Did you mark the Harmonic Balancer 1-15/32" from the zero mark?
The electronic circuitry is designed to deliver correct fuel timing when the sensor is set at 25 degrees after TDC.
If not then check Caspers Electronic site, his cam tool makes the adjustment a lot easier, also read the installation PDF file
http://www.casperselectronics.com/store2/product_info.php?cPath=61_62_5_6_8&products_id=1488
The electronic circuitry is designed to deliver correct fuel timing when the sensor is set at 25 degrees after TDC.
If not then check Caspers Electronic site, his cam tool makes the adjustment a lot easier, also read the installation PDF file
http://www.casperselectronics.com/store2/product_info.php?cPath=61_62_5_6_8&products_id=1488
I've checked the fuel pressure, I think it was around 37, have tried with and without MAF plugged in, crank sensor is plugged in, didn't mess with the plug wires. I made my own mark on the harmonic balancer at 1.45 inches counter clockwise of the mark on the balancer.
When I crack the throttle open, it does make it want to start even more. I'll try turning the cam sensor till it runs. I was pretty sure that I lined up the dots correctly when changing sprockets, but could've screwed that up i guess. It seems like you can't get the bottom sprocket one wrong because of the keyway on the crank. And the two bolts on cam for the top sprocket sit perfectly level when that dot is lined up with the sprocket on the crank, and it seemed that way when I put em on, but i'm trying rule out everything else before I dig back in to check that.
I'll check for pinched wires, and turning the cam sensor till it runs. Stock injectors, and TurboJKT should know the chip.
Thanks everyone for the help thus far!
I'll check for pinched wires, and turning the cam sensor till it runs. Stock injectors, and TurboJKT should know the chip.
Thanks everyone for the help thus far!
Its got a RED ARMSTRONG chip. I couldn't find pinched wires, unfortunately. I tried turning the cam sensor a little at a time and trying to start it each time, but it got worse as it furthered from the spot where it was set, I went 180 degrees, and back trying to start it every lit bit I moved it. It still wants to start when I get back to where I had it set. I think it's time to tear it down and check the the sprocket dot alignment, maybe i'll find something else I did wrong along the way. If I lined up the dots wrong, how to do get right now?
GNONYX
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I don't know if you set the #1 piston in the top position when you can see the piston head, and also see if the balancer marking is on 25* TDC.
Make sure all is checked before you start tearing down the timing cover again.
I don't know if you have this or not, but read it and apply it to your problem; I hope this helps you out
http://www.vortexbuicks-etc.com/cam_sensor.htm
Make sure all is checked before you start tearing down the timing cover again.
I don't know if you have this or not, but read it and apply it to your problem; I hope this helps you out
http://www.vortexbuicks-etc.com/cam_sensor.htm
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It's hard to mess up on the cam timing. Do you really think there is a chance?
Have you looked at the plugs? Are they wet? Dry?
RL
Have you looked at the plugs? Are they wet? Dry?
RL
Buick Mark
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Are you sure the fuel pump ecentric is positioned the correct way? If not, the cam sensor gear will bind/jam.
GNONYX
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I'm not being a smart a_s, but what is the fuel pump which is located in the fuel tank has to do with the cam sensor which is located in the engine compartment?
No security
The number one plug is wet after cranking, and i've pulled the number one plug while cranking to watch is spark. Lots of spark.. Should I check all the plugs for spark, and to see if they're wet?I really don't think I could've messed up the dots on the sprockets, it seemed pretty simple. but I didn't check for top dead center or anything when changing the actual sprockets, just turned the motor till the dots lined up on the old sprockets, pulled em and put the new ones on.
When setting the cam sensor, I would get it set, and try starting with the result of it sputtering and almost starting. Then I would put the motor at the opposite TDC, and set it the same way, always getting the same results. I had difficulty making sure that i was on the TDC compression stroke, because when I'd put my finger over the hole of the spark plug while having someone crank the motor slowly with the intercooler fan, it felt like air was coming out of the hole every time the timing mark(my timing mark at 1.45" to the left) on the harmonic balancer would come to the 0 degrees mark. But I tried setting the cam sensor almost thirty times, trying the two methods i'm familiar with.
turboc87gn
Darkside in Detroit
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