Help - replaced timing belt, car wont start, backfires through intake.
#1
Help - replaced timing belt, car wont start, backfires through intake.
I finished replacing the timing belt today, and tried starting the car, but it wont start - it cranks, and after a few cranks it backfires smoke through the intake (makes horrible sound during the backfire too). I checked for spark, and both banks have spark. I cranked the car until crank pulley aligned with the "0" mark, removed timing belt/distributor covers to check cam gears, and they are aligned with corresponding marks.
I have no idea what else to check. Spark is there, timing seems to be correct, backfire indicates presence of fuel and air, right? What else can it be?
The only thing that I can think if, is maybe I messed up the cams? When I was trying to remove the crank bolt, I turned the crank counter clockwise a few times while I still had the old timing belt on, and so the cam gear turned clockwise as well, and the manual says not to do that (I didn't realize it when I turned them counter clockwise). Could I have messed up the position of the valves/cams by doing that? Is that likely to cause permanent damage?
I have no idea what else to check. Spark is there, timing seems to be correct, backfire indicates presence of fuel and air, right? What else can it be?
The only thing that I can think if, is maybe I messed up the cams? When I was trying to remove the crank bolt, I turned the crank counter clockwise a few times while I still had the old timing belt on, and so the cam gear turned clockwise as well, and the manual says not to do that (I didn't realize it when I turned them counter clockwise). Could I have messed up the position of the valves/cams by doing that? Is that likely to cause permanent damage?
#4
By the way, I tried disconnecting the ignition coils - one at a time, to see if I could get it to start with just four cylinders - no cigar. However, when the driver side coil is connected, it backfires, the passenget side just keeps cranking, no backfire. Checked for spark, and all cylinder have spark.
#5
Lexus Test Driver
It sounds to me like your problem lies with the timing somewhere. If not the ignition timing, then the timing of the valves relative to the crankshaft. I've never done a timing belt job before though, so this is all speculative.
#6
Update:
Sure enough I had the timing belt on wrong. On the drivers side cam pulley there's another mark, and I had it aligned with that mark. It was about 10 teeth off. I reinstalled the belt and reassembled everything back together. Charged the battery, cranked her up and she started right up without much drama. Drove around for an hour or so, temperature is normal, no visible leaks. Runs and accelerates smoothly, but I didnt take it over 2500 RPMs because my crank pulley isnt tighened fully. Will deal with that tomorrow. Thanks everyone for your help, and thaks God this is a non-interference engine!
Sure enough I had the timing belt on wrong. On the drivers side cam pulley there's another mark, and I had it aligned with that mark. It was about 10 teeth off. I reinstalled the belt and reassembled everything back together. Charged the battery, cranked her up and she started right up without much drama. Drove around for an hour or so, temperature is normal, no visible leaks. Runs and accelerates smoothly, but I didnt take it over 2500 RPMs because my crank pulley isnt tighened fully. Will deal with that tomorrow. Thanks everyone for your help, and thaks God this is a non-interference engine!
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