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Discussion Starter · #1 ·
Background...I left the radiator cap loose one day after checking my fluids, and my son drove the car next. Boiled off the coolant, and blew the head gasket (constant air in radiator hose after refilling, air bubbles from under upper intake manifold). Car ran fine before this. Did my first ever head gasket replacement, based on lots of youtube videos. Went fine. Re-assembly took a while because I didn't take photos of where each plug of the wiring harness went. But finally found a home for all the plugs. Broke the vacuum hose for the purge valve solenoid & replaced with some clear air hose. Other than that, no issues re-assembling.

Now I start it, and it'll catch and run for maybe 2 seconds before dying. It sounds normal, up until it dies. If I start it with the accelerator all the way to the floor, it'll run (poorly) for maybe 4 seconds before dying.

I know that it must be something I did wrong in the re-assembly, but where do I start? I have no idea how to even diagnose something like this. Any ideas on what I can check first?
 

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Sounds almost like a fuel pump/security issue after having the battery disconnected. Someone may have a quick fix for this.
 

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Discussion Starter · #3 ·
All I can think of at this point is to disassemble what I did before and re-assemble, checking the wiring harness as I do...given how old it is, maybe there's a chance that one of the wires broke while I was handling it?
 

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That's not really necessary. I'd just look over your wiring for the ignition harness and make sure the ground is mounted clean for it. If you search for posts about "doesn't start" or "won't start" etc., you'll see a variety of minor issues that should be easily addressed or eliminated from your list.
 

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Discussion Starter · #5 ·
Someone suggested that I check the MAF. I pulled the plug on it, and it ran for a good 30 seconds before it started to sputter a little (probably from having the MAF disconnected). So, that it encouraging. I shut the engine off because I was spewing coolant everywhere (snapped off a bolt on the radiator hose/themostat mount and only had 1 in)

But why would the MAF be the problem? It was fine before the overheating incident. And this MAF is only a year old (though it is a cheaper chinese part and not the expensive OEM MAF)
 

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You may have gotten the filaments dirty somehow? ($6 cleaner spray takes care of that). There's all sorts of new info you're now sharing, so the troubleshooting gets picky.
 

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Discussion Starter · #7 ·
I cleaned it with MAF cleaner, plugged it back in and the car went back to dying after 2 seconds. Unplugged it again and it runs. I honestly didn't know that the MAF would shut the car off.
 

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Sounds like it either got messed up during the overheating, or the wiring harness to it needs to be checked over. You can get a replacement from a junkyard for cheap, and not have to spend much for an OEM part that doesn't usually fail.
 

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Discussion Starter · #10 ·
UPDATE: I cleaned both the old, OEM MAF that I still had, and the replacement chinese MAF, and neither would allow the engine to run more than 2 seconds. But with the MAF unplugged, it cranks and runs. I ran it for about 15 minutes today. It idles rough below 1500 rpm, and has a clatter that it's never had before. I took a video of it, and you can see the tensioner pulley jiggling the whole time. I'm assuming that clatter/rough idle is due to it running without a MAF. Going to get a new OEM one from rockauto.com and see if that does the trick. I've learned my lesson with the cheap knock off parts.

Here's the video of the engine running/tensioner with clatter.


Thanks for everyone's help!

Pepper...
 

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Discussion Starter · #11 ·
UPDATE 2: I installed the new MAF from Hitachi, and it now cranks and runs. The clatter isn't as bad as it was, but it's still there. It's throwing a DTC P0300 code, and after checking online, one of the common causes is air leakage in the intake manifold. I did install a new one when I replaced the head gasket, but after I did that, I read somewhere that I was supposed to put a large glop of RTV in each corner of the Upper Intake Manifold. I didn't do that, so will try the "squirting water" technique today to see if that's the problem.

MERRY CHRISTMAS to all !!!
 

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The RTV is supposed to seal the corners of the 4 separate lower manifold gaskets to the block/head interfaces (I just filmed this on my upgrade build, but haven't stitched it together for YouTube, yet). The upper manifold should seal fine with a regular gasket.

I will say until my dying breath, you should have a scantool of some sort when diagnosing these engines beyond a minimal level. Now that there's been ELM Bluetooth OBDII scanners for under $15 on Amazon for the last decade, I can't suggest that enough as a minimum way of knowing what your PCM is trying to tell you.

Also, hunting around with a small hose as a stethoscope is my preferred method to find any vacuum leaks, but it's up to you on your engine.
 

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Discussion Starter · #13 ·
I do have an Innova OBDII Scan tool, that's how I got the P0300 DTC. Now just have to troubleshoot it. I'd love a more advanced scan tool that connects to my computer, but it hasn't been in the budget.
 

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The ELM will monitor actual PIDs, or live sensor readings for things like MAF frequency, MAP sensor, O2 readings, along with the Long and Short Term fuel trims (crucial for seeing how your engine is trying to compensate for issues outside of normal +/- 5-10% fuel adjustment ranges).

The miss could be caused by a lean condition, or something else that you can have more info to inform. Check for leaks, and see where it goes from there. You're already dealing with this longer than I'd be fine with.
 

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Discussion Starter · #15 ·
The ELM will monitor actual PIDs, or live sensor readings for things like MAF frequency, MAP sensor, O2 readings, along with the Long and Short Term fuel trims (crucial for seeing how your engine is trying to compensate for issues outside of normal +/- 5-10% fuel adjustment ranges).
Well thats awesome. I'm going to get one of these, thanks!

You're already dealing with this longer than I'd be fine with.
Don't give me too much credit, I can only work on the car about an hour a week, and won't drive it until it's 100%
 

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Discussion Starter · #17 ·
I think it may be a bad spark plug gap. During the whole head gasket assembly process, I remember seeing one if my spark plugs had been squashed between parts and bent the lead down. I just eyeballed the gap one that one and reinstalled them all. That could be the issue.
 

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If your plug got closed, you most likely chipped a piston going lean. You're chasing your tail and tossing a bunch of various issues into the conversation. All in all, you most likely want to do a pretty comprehensive look at what you've got going on. We're getting piecemeal info through the computer for the moment, and it's going to require some better in-person troubleshooting work, from the sound of it.

Edit - take this with a grain of salt, as I'd rather you get it right than chase multiple issues, just as I'm sure you do.
 
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