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Old 10-13-2010, 01:44 PM   #1
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Default Another "car won't start" thread

Lots of possibly meaningless background, can skip to the bottom for actual troubleshooting.

So, long story short - I turbo'd the car last spring, spun a bearing, rebuilt with M-tuned rods, honed cylinders and put in new piston rings. Reassembled and car started right up. Let it idle for about 1/2 hour to break in rings, then took it up to about 3000 rpms in increments and let it idle some more. I went inside to get a drink. When I came out it had died and wouldn't start again.

At that time I was living with my parents and there was this other girl living there with no car. I was ok to just let it sit for a while so she wouldn't ask me to use it. Then, my wife and I bought a house in January, I had shoulder surgery in March, we had another baby in June, and one more shoulder surgery in August. The car has just been sitting in my driveway this whole time with a fresh engine that wasn't working.

I finally decided to get back into it a couple weeks ago. Bought a new battery and installed and it started right up. Unbelievable!

The registration has long expired, so I pulled the turbo off to remove that variable while tuning the MS to pass emissions. Back running N/A, I drove it around the neighborhood a couple times and let it idle a bit more. Total running maybe an hour since it started again.

So, Monday I went to the DMV and got a temp tag (2 weeks) to get it on the road long enough to hopefully get it running clean to pass emissions testing. I was all excited and started her to warm up while I was putting the temp tag on. Hopped in the car and it died.

BEGIN DIAGNOSTICS Car cranks, can hear fuel pump and can hear fuel flowing in the rail, threw a timing light on #1 and saw about 18-20* BTDC while cranking. Bought one of those lights that you put on the ign wire and the bulb flashes while cranking (although it seems dim. Not sure how they're supposed to look). I thought it might be the injectors not opening, but I can smell raw fuel after cranking for a few seconds. I also see the PW in TS showing I think 7.3 while cranking.

I'm stumped. My next tests will be compression just for fun and will pull a plug to see if it maybe just doesn't have enough juice to arc.

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Old 10-13-2010, 02:26 PM   #2
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OK, definitely have spark, but either my compression tester is jacked, or I really have about no compression in at least cyls 1 and 2. Didn't even bother checking 3 and 4. Guess I need to check the timing belt, but I'm a little perplexed how I have a good cam signal to get spark timing, and yet have no compression...
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Old 10-13-2010, 02:29 PM   #3
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well, if you have spark, and have fuel, you need compression. unless your cam/ign timing is just out of whack.
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Old 10-13-2010, 02:29 PM   #4
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Well, my car was cranking had jacked up spark...and it was my cam angle sensor.
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Old 10-13-2010, 06:44 PM   #5
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HA! At least I don't think it was anything super obvious. Looks like the timing belt tensioner must have come loose. I can see that the cams are definitely not lined up to each other, and there is about 1/2" of play in the TB between the 2 cams. Amazing it was working at all before that. Must have just randomly skipped teeth while idling...
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Old 10-14-2010, 11:37 AM   #6
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Ripped into the front of the engine last night. The belt had skipped about 6-7 teeth on the intake cam gear. I think I remember last time I put it together that I was afraid I had the tensioner too tight, so I backed it off a bit. Obviously it wasn't tight enough. This time I got it good and snug, but I'm curious now if there is any potential danger with it too tight.
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Old 10-14-2010, 12:15 PM   #7
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all you need to do is let the tensioner spring apply pressure, then tighten. no extra force is required.

does it run now?
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Old 10-14-2010, 04:42 PM   #8
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LOL, well I remember once I tore my timing belt off because I forgot to plug my coil up. When i did plug it up it shot hella flames and i thought timing was off. So i tore my engine apart again to find that everything was spectacular. ****.
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Old 10-15-2010, 03:16 AM   #9
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Quote:
Originally Posted by Braineack View Post
all you need to do is let the tensioner spring apply pressure, then tighten. no extra force is required.

does it run now?
I must have a weaker tensioner spring, that's way too loose. I was putting more pressure than that last time and it still skipped.

Ya, it runs now. Unfortunately I think I have a clogged oil port and the block is starving. I guess I'll check back in a couple months when I finally get some time to rip it back apart and have the machine shop clean the block. Later.
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