Engine Backfire Diagnosis Led to Wiped cam Lobes
- Thread starter Skweegle89
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Skweegle89
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I'm wondering if I shouldn't pick up an intake gasket as well and swap them out. The guy that's helping me also says it seems like a huge vac leak and I'm thinking that when I left that bolt out during the carb swap it may have broke my seal. On the other hand, I'm tired of throwing money at this thing and having no idea what the problem is.
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I'm wondering if I shouldn't pick up an intake gasket as well and swap them out. The guy that's helping me also says it seems like a huge vac leak and I'm thinking that when I left that bolt out during the carb swap it may have broke my seal. On the other hand, I'm tired of throwing money at this thing and having no idea what the problem is.
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350runner
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Compression test will tell you all you need to know. It's one thing you have to do b4 buying a used vehicle. Else you wind up with a headache.
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Agreed, before doing anything else and spending any more money, need to do a compression test and/or pull the valve covers for inspection.
Actually I do. Looking to sell?
Actually I do. Looking to sell?
Skweegle89
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Probably. I was going to keep them when I found out I was getting this 454, but will probably run headers on it.
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Probably. I was going to keep them when I found out I was getting this 454, but will probably run headers on it.
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Those gaskets will work great with headers, you should probably just keep them.
Skweegle89
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10-4
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10-4
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NO, there are still plenty of scenarios. Could be a flat cam lobe, could be jumped timing, could be a major vac leak, could be a burnt valve. Compression test is going to tell alot. Not sure why you need new plugs to do a compression test.
Skweegle89
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I was told the engine needed to be up to temp to do the test. It won't run unless I put new plugs in. It will idle ****** enough with new plugs to get the temp up before the new plugs foul out. I thought my timing chain might have jumped, but wouldn't I get erratic readings with a timing light?
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NO, there are still plenty of scenarios. Could be a flat cam lobe, could be jumped timing, could be a major vac leak, could be a burnt valve. Compression test is going to tell alot. Not sure why you need new plugs to do a compression test.
I was told the engine needed to be up to temp to do the test. It won't run unless I put new plugs in. It will idle ****** enough with new plugs to get the temp up before the new plugs foul out. I thought my timing chain might have jumped, but wouldn't I get erratic readings with a timing light?
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Sounds to me like you need to perhaps set your base timing again and start fresh. This is a pretty simple task and highly advised at this point.
If you had a bad timing chain you would see the timing light be erratic but you need to ensure the vacuum advance is take off.
Skweegle89
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I will try that as well. Timing light hasn't been erratic, and vac advance has been unplugged since I started this mess.
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I will try that as well. Timing light hasn't been erratic, and vac advance has been unplugged since I started this mess.
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Skweegle89
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And the plugs aren't just for the test. I swapped plugs out the other day and it ran WAY better. They just foul out in about 10-15 minutes. I'm trying to get it idling so I can figure out why they are fouling so fast.
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NO, there are still plenty of scenarios. Could be a flat cam lobe, could be jumped timing, could be a major vac leak, could be a burnt valve. Compression test is going to tell alot. Not sure why you need new plugs to do a compression test.
And the plugs aren't just for the test. I swapped plugs out the other day and it ran WAY better. They just foul out in about 10-15 minutes. I'm trying to get it idling so I can figure out why they are fouling so fast.
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Skweegle89
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I will do the compression test and pull the valve covers before I do anything else. If I can get it running I will go back and check for vac leaks. I will run the jumper wire to the dizzy in case I'm not getting a full 12 volts, but won't do any good until I get to town to get some new plugs, as these are toast.
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I will do the compression test and pull the valve covers before I do anything else. If I can get it running I will go back and check for vac leaks. I will run the jumper wire to the dizzy in case I'm not getting a full 12 volts, but won't do any good until I get to town to get some new plugs, as these are toast.
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