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Discussion Starter · #1 ·
Okay, so I just got finished putting together my engine after having it rebuilt while I was in there for a leaky head gasket. Surprisingly, the engine started on the second attempt, despite this being my first engine work I've done!


Excited, I got the car insured, threw on the bumper and what-not, and let it idle for a while to pump up the new lifters and clear its throat. Then I went to lightly enjoy the fruits of my labor!



...aaaaaannnnd that's when it stalled under full throttle halfway out of my driveway. :? Granted it was a hill, but that just ain't right. I could only barely get up using momentum.

The symptoms are as follows:
- Starts up very easily - usually within about a second of cranking
- Idles very smoothly and quietly - 1000RPM cold, 800 warm
- Revs up completely in neutral with decent throttle response
- After rev, RPM drops to about 100-200 or fall out stalls unless gas is given
- Under partially engaged clutch in the 1000 RPM's, engine RPM oscillates up/down about twice per second
- EXTREMELY low power when driving - under full throttle 0-20 took about 4 seconds

My initial guess was be that the timing is off, but I checked about 15 million times to make sure the flywheel and camshaft marks line up. And there were definitely 5 distinct compression strokes by hand cranking. Irregardless, I'm going to check that tomorrow. Could there be anything else I should check that may be the what's bogging the engine down so much?

Any help would be appreciated!

Additional info - spark plugs were just replaced with Bosch plugs from ECS - carefully handled, but did not gap them. Should I have?
And just to be sure I'm setting the timing right, I'd like to confirm I'm lining the flywheel up right

 

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Yes the 0 should be split by the point(your with this mark) Are the cams timed correctly? Otherwise I start looking over all the electrical connectors focus on MAF TPS and ISV. Make sure your TPS is adjusted properly. Could be a myriad of things really but without having the car in front me I can only guess. The factory bosch f5dpor spark plugs come pre-gapped.
 

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x2 for double checking ALL your electrical connections & Grounds.
 

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Aktapod said:
Okay, so I just got finished putting together my engine after having it rebuilt while I was in there for a leaky head gasket. Surprisingly, the engine started on the second attempt, despite this being my first engine work I've done!

The symptoms are as follows:

- After rev, RPM drops to about 100-200 or fall out stalls unless gas is given
- Under partially engaged clutch in the 1000 RPM's, engine RPM oscillates up/down about twice per second

- EXTREMELY low power when driving - under full throttle 0-20 took about 4 seconds
-Engine drops rpm / Revs oscilate
I'd look to the TPS, making sure it 'clicks' when throttle returns to idle? You'd not think so, but without the TPS set up correctly, all sorts of weird things go on (And you can get a bad 'TPS' code, if you check the codes)

-Low power
Got any intake leaks or hosees connected incorrectly maybe?
 

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i vote for pulling codes and also checking for vacuum/boost leaks. A large leak could cause the symptoms you are having.
 

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Discussion Starter · #7 ·
:thanks: Wow, you guys nailed it right on the spot!

Upon checking, I found the TPS only partially plugged in (Woops! Must have hurried a little too much after putting the valve cover on again) and it made a world of difference! I hadn't realized it was so critical a component. So now, I could actually drive the car on the highway, but the car really bogged down, and even cut fuel as you put your foot down more. I was well aware that I had a vacuum leak, as I had run out of (or rather lost) my replacement line before I could finish, but I didn't think one line would be too big a deal in the meantime.

One line is too big a deal in the meantime.

WOOOOOWWWW! I've never felt the 200 pull like that. After plugging the leak, I actually laughed from a mixture of surprise, excitement, and enjoyment on my first drive. Thank you all so much!
 

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Awesome! Great job to you and to everyone else helping so quickly on this frustrating issue. MG FTW!
 

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Aktapod said:
:thanks: Wow, you guys nailed it right on the spot!
One line is too big a deal in the meantime.

WOOOOOWWWW! I've never felt the 200 pull like that. After plugging the leak, I actually laughed from a mixture of surprise, excitement, and enjoyment on my first drive. Thank you all so much!
Nailed it, because of the internets! What *did* we do before we had the intarwebs, anyway?

And say.. What was the vaccum line that was missing/ undone, that managed to steal all your powerz? :)
 

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Discussion Starter · #12 ·
I love this forum. :heart:

And it was just the one nearest the radiator that goes to A/C and diff lock. The original braided lines pretty much disintegrated to the touch about a year ago and got replaced, but I didn't know what to do with this one that had turned itself to granite. Originally, I just taped a new line to the solid old one since it kept slipping off its connector, but this was so leaky I figured it was the same if I just left it off after I lost that segment. It was apparently more effective than I thought.

However, this is my latest ingenious parking garage fix:



On a side note, does anyone know where I can get an *actual* replacement that would fit to the manifold, as well as the larger end on the double T fitting thingy?
 

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Discussion Starter · #14 ·
Hahaha! Sorry, I thought that made-up term might cause some confusion, but least is was better than saying Pi fitting

This guy here:


My concern is that the connection to that is much larger than that on the back of the intake manifold, so my usual vacuum line doesn't fit over it, but one that did would slip off the manifold.
 

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If you get the old bit of vinyl vac line off the check valve using some gentle heat from a heat gun and razor. You could then heat the end of the line and and re-attach it to the check valve. Otherwise a piece of fuel hose would work to connect the two.
 
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