NB2 Won't Start After Timing Belt
11-18-2015, 03:36 PM
#21
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Hey everyone, I appologize for the wait. Here is what the timing belt looks like right now. This is the exact position of the belt that caused the car to not run. Or, at least I think it caused it to not run. Does it look ok? I'll use that video's tooth counting method to check.
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11-18-2015, 07:21 PM
#26
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Hmm.. No, there are no missing grounds. There weren't any before the timing belt was removed. This is why I am so confused. The car ran fine before I adjusted the timing belt, and now that I have pretty much been confirmed that it is not a timing issue, I have no idea what it could be.
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11-18-2015, 07:25 PM
#27
Hmm.. No, there are no missing grounds. There weren't any before the timing belt was removed. This is why I am so confused. The car ran fine before I adjusted the timing belt, and now that I have pretty much been confirmed that it is not a timing issue, I have no idea what it could be.
Should be convex side toward the radiator.
Last edited by good2go; 11-18-2015 at 08:06 PM.
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11-19-2015, 01:31 AM
#29
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My impression is that being off one tooth won't prevent it from starting. It may stumble and idle poorly, or it may have no top end (depending on which way you're off), but it will start.
I agree that the most likely cause is electronics. Do you have a stock ECU, or aftermarket? If aftermarket, many of those have cam/crank pulse debugging tools. If it's a stock ECU, you might be able to hook up an OBD2 scanner and see if it outputs an RPM value while cranking (not sure if the stock ECU does or not). If you get an RPM signal, you know the cam/crank pulses are good.
You say you think you smell gas -- do you actually? If so, then your cam/crank signals are good (ECU won't inject fuel without a sync) and that would suggest it's probably a spark problem.
Stupid question, but you did get the plug wires back on the right cylinders, right?
On the "missing ground" topic, the main ECU harness is grounded through a bolt at the front of the intake manifold. The harnesses are somewhat in the way for the timing covers, so it's not unusual to take that bolt out to get more flexibility in the harness, and if you forgot to put it back on, or missed one of the ring terminals that goes under it...
--Ian
I agree that the most likely cause is electronics. Do you have a stock ECU, or aftermarket? If aftermarket, many of those have cam/crank pulse debugging tools. If it's a stock ECU, you might be able to hook up an OBD2 scanner and see if it outputs an RPM value while cranking (not sure if the stock ECU does or not). If you get an RPM signal, you know the cam/crank pulses are good.
You say you think you smell gas -- do you actually? If so, then your cam/crank signals are good (ECU won't inject fuel without a sync) and that would suggest it's probably a spark problem.
Stupid question, but you did get the plug wires back on the right cylinders, right?
On the "missing ground" topic, the main ECU harness is grounded through a bolt at the front of the intake manifold. The harnesses are somewhat in the way for the timing covers, so it's not unusual to take that bolt out to get more flexibility in the harness, and if you forgot to put it back on, or missed one of the ring terminals that goes under it...
--Ian
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11-19-2015, 01:36 PM
#31
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Thank goodness I have a spare engine sitting around. I'll salvage a cam sensor from it after I put my engine back together and see if that fixes it. 
Ian, thank you for a very intelligent and insightful answer. I love it when people explain things so thoroughly and in a "point A leads to B, which causes C" manner. I will test the spark after everything is buttoned back up.
Ian, thank you for a very intelligent and insightful answer. I love it when people explain things so thoroughly and in a "point A leads to B, which causes C" manner. I will test the spark after everything is buttoned back up.
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11-30-2015, 01:39 PM
#35
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The car literally ran absolutely fine before I removed the timing belt because it was too tight. I put the belt back on, and it won't start. I'll check the connectors, but I am pretty sure they are all clicked. The ECU hasn't been touched in a long time. All of the grounds are good too.
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11-30-2015, 02:12 PM
#38
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99% of the time, if you took it apart and put it back together and it doesn't work, it's something you put back wrong.
Have you pulled the plugs? Is it injecting fuel? Is it sparking?
--Ian
Have you pulled the plugs? Is it injecting fuel? Is it sparking?
--Ian
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