Running Rich Grand Am SE
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Running Rich Grand Am SE
I got a 95 Pontiac Grand Am (SE 4 cylinder) , that I just did a head gasket on and it is running way to rich.
I have black smoke out the tailpipe, only starts if I give it wide-open throttle (give the engine air), and a clear misfire (possibly on 2 cylinders!)
I have no check engine light, and I cleaned and re-gapped the plugs today to remove a variable of cause.
about 190,000 miles, what should my main suspects be? I was only able to get it to idle long enough to check 2 injectors with a screwdriver but the engine was shaking so much from the misfire I couldn't tell if the ticks were sporadic or not, just know they were clicking. (Also checked airbox)
The injectors are really hard to get to if I were to change them so I was curious what my causes could be, or if there was a common problem with a specific sensor around this mileage. (Once again no check engine light so not sure if its a sensor)
I have black smoke out the tailpipe, only starts if I give it wide-open throttle (give the engine air), and a clear misfire (possibly on 2 cylinders!)
I have no check engine light, and I cleaned and re-gapped the plugs today to remove a variable of cause.
about 190,000 miles, what should my main suspects be? I was only able to get it to idle long enough to check 2 injectors with a screwdriver but the engine was shaking so much from the misfire I couldn't tell if the ticks were sporadic or not, just know they were clicking. (Also checked airbox)
The injectors are really hard to get to if I were to change them so I was curious what my causes could be, or if there was a common problem with a specific sensor around this mileage. (Once again no check engine light so not sure if its a sensor)
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Joined: Feb 2015
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Too early to ask this question because . . .
You changed the head gasket. That involved removing the head.
This engine is an overhead cam engine, so the timing chain runs from the crank to the cam(*) in the head. It needs to be properly timed and is always timed the same way (if all goes well).
Since you removed the head (and therefore the relationship between the crank and cam(*) ) , you would have needed to get this relationship correct when you reassembled everything, otherwise risking the mechanical timing being incorrect. If this is the case, any number of things can be wrong (depending on how far incorrect the timing is) with the timed rotating process including what you describe.
I'm not giving you a hard time, but your questions tell me that I should tell you this: Mechanical timing between the crank and cam(*) needs to be set up precisely. It'* not just a rotating assembly like a water pump or alternator. It has to be mechanically timed properly.
In the case of your repair, I would have rotated the #1 cylinder to TDC then marked the chain and cam gear(*) at a point such that I could put it back that way during reassembly. Did you do this?
If not, then it is likely you have a mechanical timing issue.
You changed the head gasket. That involved removing the head.
This engine is an overhead cam engine, so the timing chain runs from the crank to the cam(*) in the head. It needs to be properly timed and is always timed the same way (if all goes well).
Since you removed the head (and therefore the relationship between the crank and cam(*) ) , you would have needed to get this relationship correct when you reassembled everything, otherwise risking the mechanical timing being incorrect. If this is the case, any number of things can be wrong (depending on how far incorrect the timing is) with the timed rotating process including what you describe.
I'm not giving you a hard time, but your questions tell me that I should tell you this: Mechanical timing between the crank and cam(*) needs to be set up precisely. It'* not just a rotating assembly like a water pump or alternator. It has to be mechanically timed properly.
In the case of your repair, I would have rotated the #1 cylinder to TDC then marked the chain and cam gear(*) at a point such that I could put it back that way during reassembly. Did you do this?
If not, then it is likely you have a mechanical timing issue.
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