Replaced head gasket, now it wont start!
10-19-2012, 02:48 PM
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Replaced head gasket, now it wont start!
So I had a blown headgasket in my 94 Runner 3.0L V6.
Hired a mechanic to come over and replace the head gaskets. When he got the engine back together, we tried to start it, it turned over and kind of sputtered like it was going to start and then died. At the point where the engine stopped turning and died I heard a fairly audible knock or thump type of noise. The mechanic was not concerned so he tried to start it again. We tried many times, the engine will crank but would not sputter or cough like it was going to fire off. Pulled a sparkplug, it was soaked with gas but would still spark. At this point he decided to pull the timing belt cover back off. Sure enough, though he said it had been correct when he put it togther, it had "jumped" time. He then proceeded to reset the timing belt and then put everything back together. Long story short, we still have the same basic issue and he has thrown up his hands. Engine cranks, have fuel to the fuel rail, have spark, but it will not even cough or sputter.
If I let it sit overnight, it will cough one time when I first try to start it, any cranking after that gets me nothing.
I have looked around this sight and others and people have mentioned changing the mass airflow sensor. Is there any way to know if that is the issue before I spend $189 on a new one?
Any other suggestions?
Hired a mechanic to come over and replace the head gaskets. When he got the engine back together, we tried to start it, it turned over and kind of sputtered like it was going to start and then died. At the point where the engine stopped turning and died I heard a fairly audible knock or thump type of noise. The mechanic was not concerned so he tried to start it again. We tried many times, the engine will crank but would not sputter or cough like it was going to fire off. Pulled a sparkplug, it was soaked with gas but would still spark. At this point he decided to pull the timing belt cover back off. Sure enough, though he said it had been correct when he put it togther, it had "jumped" time. He then proceeded to reset the timing belt and then put everything back together. Long story short, we still have the same basic issue and he has thrown up his hands. Engine cranks, have fuel to the fuel rail, have spark, but it will not even cough or sputter.
If I let it sit overnight, it will cough one time when I first try to start it, any cranking after that gets me nothing.
I have looked around this sight and others and people have mentioned changing the mass airflow sensor. Is there any way to know if that is the issue before I spend $189 on a new one?
Any other suggestions?
10-19-2012, 05:28 PM
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Redid mine a year ago. I assume that the distributor was re-installed into its proper place with the wires in proper order?
When TB was installed did you hand crank it two revolutions and recheck the timing marks? If you have fuel and spark, my bet is that timing is somehow wrong. Also - were you able to run the engine fine with the blown HG,,,or before it was replaced?
When TB was installed did you hand crank it two revolutions and recheck the timing marks? If you have fuel and spark, my bet is that timing is somehow wrong. Also - were you able to run the engine fine with the blown HG,,,or before it was replaced?
10-19-2012, 06:06 PM
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The truck ran fine even with the blown head gasket, pulled it into the garage in order to start tearing it down, no issues at all.
As far as the distributor and timing go, I'm assuming that all is correct. I'm a half-ass shade tree mechanic at best, which is why I hired a guy for this job. He had good references but its possible this was over his head. I will double check the timing and distributor alignment. Is it possible to check this with a timing light and just the starter cranking the engine? Or I would I need to remove the timing belt cover again to properly check this?
As far as the distributor and timing go, I'm assuming that all is correct. I'm a half-ass shade tree mechanic at best, which is why I hired a guy for this job. He had good references but its possible this was over his head. I will double check the timing and distributor alignment. Is it possible to check this with a timing light and just the starter cranking the engine? Or I would I need to remove the timing belt cover again to properly check this?
10-19-2012, 08:22 PM
#4
Find another mechanic...
More than likely he reinstalled timing belt wrong, or put the distributor in wrong. Start with the basics, like verifying timing marks are right(crank and cams are aligned), then check that the distributor is installed properly. If it ran going into the garage, more than likely its related to something regarding the repairs, not sensors.
I'm not to informative on the 3VZ, so I'm not sure if it's an interference engine or not. If it is, and the belt was installed wrong, it's possible that a piston hitting a valve was the cause of your thump. Or it may have been a backfire. As I said, pull timing belt cover off and start with the basics. What's your location in case someone on the forum may be willing to lend a hand?
More than likely he reinstalled timing belt wrong, or put the distributor in wrong. Start with the basics, like verifying timing marks are right(crank and cams are aligned), then check that the distributor is installed properly. If it ran going into the garage, more than likely its related to something regarding the repairs, not sensors.
I'm not to informative on the 3VZ, so I'm not sure if it's an interference engine or not. If it is, and the belt was installed wrong, it's possible that a piston hitting a valve was the cause of your thump. Or it may have been a backfire. As I said, pull timing belt cover off and start with the basics. What's your location in case someone on the forum may be willing to lend a hand?
Last edited by rokblok; 10-19-2012 at 08:28 PM.
10-19-2012, 09:23 PM
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I'm located near Phoenix, Az.
My understanding is that this is a non interference motor so I shouldnt have an issue with a bent valve or anything.
Thanks for your observations, I will check out those items and let you all know what I find.
My understanding is that this is a non interference motor so I shouldnt have an issue with a bent valve or anything.
Thanks for your observations, I will check out those items and let you all know what I find.
10-20-2012, 06:53 AM
#6
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Another tip, you can drain all of the water out and start the 4runner with the TB covers off....just to see if you have it correct. I'm not sure if you can use a timing light on a vehicle that is not running..possible. Also - make sure the distributor was not re-installed 180 out....can't remember if that is possible with the 3VZE, but I have know that is possible with other motors.
One other thing I learned with the 3VZE...you must go with the timing marks on the pulleys....you cannot rely on marking the belt in relation to the pulleys. This is because as the motor turns, the number of revolutions does not match the length of the belt. As a result, if you mark the belt and then turn the motor two (or more) full revolutions and look at the belt compared to the marks, they will look like it jumped. But it did not...instead the overall length of the belt just does not match the revolutions of the gears/crankshaft. Not sure how many revolutions it takes for the belt to match back up.
Another thing to check..if yo used a new belt, count the teeth to make sure it is exact to the old belt.
One other thing I learned with the 3VZE...you must go with the timing marks on the pulleys....you cannot rely on marking the belt in relation to the pulleys. This is because as the motor turns, the number of revolutions does not match the length of the belt. As a result, if you mark the belt and then turn the motor two (or more) full revolutions and look at the belt compared to the marks, they will look like it jumped. But it did not...instead the overall length of the belt just does not match the revolutions of the gears/crankshaft. Not sure how many revolutions it takes for the belt to match back up.
Another thing to check..if yo used a new belt, count the teeth to make sure it is exact to the old belt.
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